Description:FIELD OF THE INVENTION
[0001] Embodiments of the present disclosure relate to the area of thin films and in particular it relates to films that are sustainable and eco-friendly.

BACKGROUND OF THE INVENTION
[0002] Generally, plastic films find used in a number of industries with varying application. These plastic films are used in a wide variety of applications, which include packaging, bags, labels, building construction, landscaping, electrical fabrication, photographic film, film stock for movies, video tape, etc. However major disadvantage of these films is that they are not environmentally safe and are toxic, carcinogenic and can be a health hazard causing endocrine disruption etc. Therefore, there is a need for a better and safer material to overcome these disadvantages.

SUMMARY OF THE INVENTION
[0003] Embodiments of the present disclosure relate to a method and system for obtaining a multi-layered film. An embodiment includes dissolving a non centrosymmetric polysaccharide in an solvent, wherein the solvent is an acidic medium, forming a first solution. A further embodiment includes dispensing the first solution onto a base. And a further embodiment includes drying the first solution on the base under normal temperature and pressure to obtain a multi-layered film.
[0004] A further embodiment includes a method of forming a piezoelectric nanogenerator by sandwiching a flexible multi-layered film between a first conducting tape and a second conducting tape, wherein the first conducting tape is on a top surface of the multi-layered film forming a first electrode and the second conducting tape is on a bottom surface of the multi-layered film forming a second electrode. A further method includes forming a sensor from the film. Yet a further embodiment includes forming a bio-compatible dressing from the film.
[0005] In a preferred embodiment chitosan-based organic film with multifunctional properties are disclosed that find importance and will revolutionize the field of biodegradable material. In an embodiment, a renewable and biocompatible biopolymer, with nanoparticle incorporation for color tunability, enhancing its aesthetic appeal and versatility has been disclosed. In an embodiment, the chitosan-based organic films exhibit exceptional mechanical sturdiness and robustness, making them suitable for various applications, including packaging and structural components. In an further embodiment, a unique sodium hydroxide-based crosslinking method ensures improved material integrity and durability, improving upon using other toxic chemicals like glutaraldehyde that have been previously reported for the same purpose. In a further embodiment, these organic films demonstrate the intriguing ability to undergo shape morphing, opening new avenues in adaptive materials design. In a further embodiment, these films exhibit a capacity to generate reactive oxygen species owing to their piezoelectric property, promising potential applications in advanced wound healing and tissue engineering. In a further embodiment, these materials possess inherent antibacterial activity, mitigating microbial growth and providing a sustainable solution in the fight against bacterial contamination. Other embodiments are also disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The detailed description is described with reference to the accompanying figures. Features, aspects, and advantages of the subject matter of the present disclosure will be better understood with regard to the following description and the accompanying drawings. The figures are intended to be illustrative, not limiting, and are generally described in context of the embodiments, and it should be understood that it is not intended to limit the scope of the disclosure to these particular embodiments. In the figures, the same numbers may be used throughout the drawings to reference features and components. In order that the present disclosure may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying figures. The figures together with detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages.
[0007] Figure 1A is an illustration of an exemplary process of preparing an organic based thin film in accordance with an embodiment of the present disclosure.
[0008] Figure 1B is an illustration of an exemplary process of preparing an organic based thin film with a mixture of nano-particles or nano-materials in accordance with an embodiment of the present disclosure.
[0009] Figure 2A illustrates an exemplary digital photograph of the organic film prepared in accordance with an embodiment of the present disclosure.
[0010] Figure 2B illustrates an exemplary SEM micrograph showing top surface (top panel) and cross-section (bottom panel) of the organic film in accordance with an embodiment of the present disclosure.
[0011] Figure 2C is an exemplary XRD spectra of the various organic films and nano-material based organic films prepared in accordance with an embodiment of the present disclosure.
[0012] Figure 2D is an exemplary Fourier transform infrared (FTIR) spectroscopy revealed a broad absorption band of the organic films and nano-material based organic films in accordance with an embodiment of the present disclosure.
[0013] Figure 3A illustrates an exemplary case of an piezo-electric generator formed using the organic films in accordance with an embodiment of the present disclosure.
[0014] Figure 3B illustrates an exemplary case of a sensor formed using the organic films in accordance with an embodiment of the present disclosure.
[0015] Figure 3C illustrates an exemplary case of a medicated dressing for wounds formed using the organic films in accordance with an embodiment of the present disclosure.

[0016] Figure 3A illustrates an exemplary case of the organic film in 1% acetic acid solution before and after adding 1M NaOH in accordance with an embodiment of the present disclosure.
[0017] Figure 3B illustrates an exemplary case of comparing Glutaraldehyde and NaOH cross-linked films before and after immersion in DI water for 10 min, where the scale in (B) is 10 mm, in accordance with an embodiment of the present disclosure.
[0018] Figure 3B illustrates an exemplary case Contact angle measurement of CHT, MoS2/CHT, and NaOH-CHT films in accordance with an embodiment of the present disclosure.
[0019] Figure 4A illustrates an exemplary case 400A of the organic film in 1% acetic acid solution before and after adding 1M NaOH in accordance with an embodiment of the present disclosure.
[0020] Figure 4B illustrates an exemplary case of comparing Glutaraldehyde and NaOH cross-linked films before and after immersion in deionized (DI) water for 10 min, where the scale is about 10 mm, in accordance with an embodiment of the present disclosure.
[0021] Figure 5A illustrates an exemplary case contact angle measurement of CHT, MoS2/CHT, and NaOH-CHT films in accordance with an embodiment of the present disclosure.
[0022] Figure 5B illustrates an exemplary case of an indentation study of CHT, MoS2/CHT, NaOH-CHT and NaOH-MoS2/CHT films in accordance with an embodiment of the present disclosure.
[0023] Figure 5C illustrates an exemplary case of DMA studies showing Stress versus strain curve in accordance with an embodiment of the present disclosure.
[0024] Figure 5D illustrates an exemplary case of Force versus Displacement behaviour of the films in accordance with an embodiment of the present disclosure.
[0025] Figure 5E illustrates an exemplary case Expansion in the area over 24 hours after immersing in DI water in accordance with an embodiment of the present disclosure.
[0026] Figure 5F illustrates an exemplary case Expansion in the area over 24 hours after immersing in DI water in accordance with an embodiment of the present disclosure.
[0027] Figure 6A illustrates an exemplary case of Oscilloscope measurements for gentle tapping on an organic film in accordance with an embodiment of the present disclosure.
[0028] Figure 6B illustrates an exemplary case of Oscilloscope measurements for vigorous tapping on CHT and MoS2/CHT (varying concentrations) films in accordance with an embodiment of the present disclosure.
[0029] Figure 6C illustrates an exemplary case of Comparative piezoelectric measurement in accordance with an embodiment of the present disclosure.
[0030] Figure 7A is an exemplary case of Bacterial assay displaying CFU/ml after treatment of E. coli with MoS2/CHT films under white light in accordance with an embodiment of the present disclosure.
[0031] Figure 7B is an exemplary case of Digital images of grown colonies that were obtained after 30 min of illumination with white light on MoS2/CHT films in accordance with an embodiment of the present disclosure.
[0032] Figure 8A is an exemplary case of Biocompatibility assay of CHT and MoS2/CHT films with NIH 3T3 cells for 24h and 48 h in accordance with an embodiment of the present disclosure.
[0033] Figure 8B is an exemplary case of Cellular viability of NIH 3T3 cells onto CHT film for 24 and 48 hours in accordance with an embodiment of the present disclosure.
[0034] Figure 8C is an exemplary case of Cell proliferation assay for CHT and MoS2/CHT films with and without ultra-sonication for 10 min (1 MHz) in accordance with an embodiment of the present disclosure.
[0035] .Figure 8D is an exemplary case of Time-dependent ultrasound-mediated cell proliferation assay for CHT film on NIH 3T3 cells in accordance with an embodiment of the present disclosure.
[0036] Figure 8E is an exemplary case illustrating Live/dead analysis of NIH 3T3 cells by staining with calcein (100 µm ) in accordance with an embodiment of the present disclosure.
[0037] Figure 8F is an exemplary case illustratingDAPI/Actin staining images of NIH 3T3 cells adhered onto CHT films (100 µm ) in accordance with an embodiment of the present disclosure.
[0038] Figure 9 is an exemplary illustration of the Shapes of CHT films and MoS2/CHT films before and after immersing in DI water, where AR is the aspect ration in accordance with an embodiment of the present disclosure.
[0039] Throughout the drawings, identical reference numbers designate similar, but not necessarily identical elements. The figures as disclosed herein are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings are meant to only be provided as examples and/or implementations consistent with the description, and the description may not be limited to the examples and/or implementations provided in the drawings.

DETAILED DESCRIPTION
[0040] The following describes technical solutions in exemplary embodiments of the subject matter of the present disclosure with reference to the accompanying drawings. In this application as disclosed herein, "at least one" means one or more, and "a plurality of" means two or more. The term "and/or" describes an association relationship for describing associated objects and represents that three relationships may exist. For example, A and/or B may represent the following cases: Only A exists, both A and B exist, and only B exists, where A and B may be singular or plural. The character "/" usually indicates an "or" relationship between the associated objects. "At least one item (piece) of the following" or a similar expression thereof means any combination of the items, including any combination of singular items (piece) or plural items (pieces). For example, at least one item (piece) of a, b, or c may represent a, b, c, a and b, a and c, b and c, or a, b, and c, where a, b, and c each may be singular or plural.
[0041] It should be noted that in this application articles “a”, “an” and “the” are used to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. The terms “comprise” and “comprising” are used in the inclusive, open sense, meaning that additional elements may be included. It is not intended to be construed as “consists of only”. Throughout this specification defined above, unless the context requires otherwise the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated element or step or group of elements or steps but not the exclusion of any other element or step or group of elements or steps. The term “including” is used to mean “including but not limited to”. “Including” and “including but not limited to” are used interchangeably. In the structural formulae given herein and throughout the present disclosure, the following terms have been indicated meaning, unless specifically stated otherwise.
[0042] Unless otherwise defined, all terms used in the disclosure, including technical and scientific terms, have meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included for better understanding of the present disclosure. The term ‘about’ as used herein when referring to a measurable value such as a parameter, an amount, a temporal duration, and the like, is meant to encompass variations of ±10% or less, preferably ±5% or less, more preferably ±1% or less and still more preferably ±0.1% or less of and from the specified value, insofar such variations are appropriate to perform the present disclosure. It is to be understood that the value to which the modifier ‘about’ refers is itself also specifically, and preferably disclosed.
[0043] It should be noted that in this application, the term such as "example" or "for example" or “exemplary” is used to represent giving an example, an illustration, or descriptions. Any embodiment or design scheme described as an "example" or "for example" in this application should not be explained as being more preferable or having more advantages than another embodiment or design scheme. Exactly, use of the word such as "example" or "for example" is intended to present a related concept in only a specific manner.
[0044] It should be understood that in the embodiments of the present subject matter that "B corresponding to A" indicates that B is associated with A, and B can be determined based on A. However, it should be further understood that determining B based on A does not mean that B is determined based on only A. B may alternatively be determined based on A and/or other information.
[0045] In the embodiments of this application, "a plurality of" means two or more than two. Descriptions such as "first", "second" in the embodiments of this application are merely used for indicating and distinguishing between described objects, do not show a sequence, do not indicate a specific limitation on a quantity of devices in the embodiments of this application, and do not constitute any limitation on the embodiments of this application.
[0046] Exemplary Embodiments of the present disclosure relate to a method and system for obtaining a multi-layered film. An embodiment may include dissolving a non centre-o-symmetry polysaccharide in an solvent, wherein the solvent is an acidic medium, forming a first solution. A further embodiment may include dispensing the first solution onto a base. And a further embodiment may include drying the first solution on the base under normal temperature and pressure to obtain a multi-layered film. A further embodiment may include treating the multi-layered film with a basic solution. In a further embodiment, the basic solution is a cross linking agent. In a further embodiment, wherein treating the multi-layered film with the basic solution may include creating cross-links in the multi-layered film. A further embodiment may include neutralizing residual solvent in the multi-layered film. In a preferred embodiment, the basic solution may be a metal hydroxide. In an exemplary embodiment, the metal hydroxide may be NaOH. In a exemplary embodiment, a concentration of the basic solution may vary in the range from about 50 mM to about 1 M, wherein an extent of degradation of the multi-layered film may be determined by the concentration of the basic solution.
[0047] In an exemplary embodiment, the base may be a substrate comprising a synthetic fluoropolymer of tetrafluoroethylene. It should be obvious that other material made be used as a base and all such materials used as a base fall within the scope of the present disclosure. In an exemplary embodiment, the multi-layered film may be transparent or translucent. In an exemplary case, for the organic films prepared in accordance with the embodiments of the present disclosure, transparency ranges from being a completely transparent multi-layered film to a completely translucent multi-layered film. In an exemplary case, the transparency of the multi-layered film is associated with varying degrees of light penetration in the multi-layered film.
[0048] In an exemplary case, a thickness of the multi-layered film may be variable, wherein the thickness of the multi-layered film may depend on the volume of the first solution dispensed on the base. In an exemplary case, the thickness of the multi-layered film may be in the range of about 20 µm to about 150µm. Inan exemplary case, the multi-layered film treated with the basic solution may display/ exhibit no degradation or extremely slow degradation when placed in water. In an exemplary case, the multi-layered film not treated with the basic solution may degrade when deposited in water, and the rate of deposition may vary. In an exemplary case, the multi-layered film immediately degrades when deposited in a mild acidic solution or a mild solution of vinegar, this may also be referred to as on-demand degradation.
[0049] In an exemplary case, the concentration of the acidic medium may vary from about 0.1 % to about 5 %, and wherein the acidic medium facilitates faster degradation of the multi-layered film treated with the basic solution. In an exemplary case, the multi-layered film may undergo shape-morphing when deposited in a solution, wherein the solution may be an acidic solution or a basic solution or a pH neutral medium. In an exemplary case, the rate of shape-morphing is slower in the acidic solution or the basic solution compared to the rate of shape-morphing in a pH neutral solution.
[0050] In an exemplary case, the multi-layered film may undergo deformation at a slow rate exhibiting degradation and/or reverse shape morphing when placed in a solution with a pH = 4. In an exemplary case, the multi-layered film may undergo deformation at a faster rate exhibiting reverse shape morphing and the multi-layered film being intact when placed in a solution of 4 < pH < 9. In an exemplary case, the multi-layered film may undergo bi-directional shape morphing and reverse shape morphing when placed in a solution of pH > 9.
[0051] In an exemplary case, drying the film at room temperature on a substrate creates a differential gradient across the multi-layered film. In an exemplary case, the differential gradient may lead to formation of different sized pores across different layers of the multi-layered film. In an exemplary case, because of faster drying on the top, the pore size on the top of the film may be smaller compared to the pore size on the bottom of the film (proximate to the substrate), which take longer to dry in normal temperature and pressure conditions. In an exemplary case, the cross-linked regions in the multi-layered film are sparse on a first side, wherein the first side of the film is proximate with the base (bottom side of the film). In an exemplary case, the cross-linked regions are dense on a second side of the film, wherein the second side is away from the base (top side of the film). In an exemplary case, the pores on the first side are larger in size compared to the pores on the second side which are smaller. In an exemplary case, the size of the pores on the first side are large due to faster drying time and the size of the pores on the second side are smaller due to slower drying time.
[0052] In an exemplary case. a nano-material composite may be added to the first solution, wherein the nano-particle composite dissolves in the first solution forming a mix-solution. In an exemplary case, the color of the film may be dependent or derived from the nano-material composite. In an exemplary case, the mix-solution is dispensed onto a base, wherein the base is a substrate comprising a synthetic fluoropolymer of tetrafluoroethylene. As exemplary case includes drying the solvent from the mix-solution at under normal temperature and pressure to obtain a film. In an exemplary case, a composition the nano-material composite in a range from 1mg to 100 mg. In an exemplary case, the nanomaterial composite soluble under mild acidic conditions is incorporated into the first solution. In an exemplary case, the nano-material composite includes an ore of a transition material or an oxide of a transition material or MoS2 or carbon nanoparticles.
[0053] An exemplary case includes forming a piezoelectric nanogenerator. An exemplary case may include sandwiching a flexible multi-layered film between a first conducting tape and a second conducting tape. In an exemplary case, the first conducting tape is on a top surface of the multi-layered film forming a first electrode. In an exemplary case, the second conducting tape is on a bottom surface of the multi-layered film forming a second electrode. In an exemplary case, the flexible multi-layered film formed by the method disclosed previously.
[0054] In an exemplary case, a potential difference may be generated across the first electrode and the second electrode on application of a pressure on the multi-layered film due to the flow of electrons between the first electrode and the second electrode. In an exemplary case, the potential difference may be measured as an output voltage across the first electrode and the second electrode. In an exemplary case, the first conducting tape and the second conducting tape comprises at least one of a metal conductor or a non-metallic conductor. In an exemplary case, the first conducting tape and the second conducting tape may include at least one of an organic conductor or an in-organic conductor. In an exemplary case, the output voltage may include a high signal-to-noise ratio.
[0055] In an exemplary case, addition of a nano-material composite to the multi-layered film may result in increasing a mechanical strength and flexibility associated with the multi-layered film. In an exemplary case, addition of a nano-material composite to the multi-layered film may exhibit a higher electrical potential compared to a normal film. In an exemplary case, the voltage of the normal film is in the range of about 0.9V. In an exemplary case, the voltage of the nano-material composite based films was in a range from about 1 Volts to about 3 Volts depending on the concentration of the nano-material composite. An exemplary case may include a device and/or a system formed by the method as disclosed previously.
[0056] An exemplary case may include a sensor formed by the method disclosed above. In an exemplary case, the multi-layered film is provided with an ink, and the ink is sensitive to measurable parameter. In an exemplary case, the measurable parameter is at least one of a pressure and/or a voltage and/or a temperature and/or a wavelength and/or a composition and/or a stress and /or a strain and/or a force and/or a weight and/or a volume and/or a size and/or a force and/or a humidity and/or a flow velocity and/or luminosity.
[0057] An exemplary case includes a plastic formed by the method as disclosed previously. In an exemplary case, a color of the plastic may be determined and dependent on the nano-particle composite.
[0058] An exemplary case includes a biocompatible dressing formed by the method disclosed previously. In an exemplary case, the dressing exhibits photocatalytic activity wherein bacterial activity was reduced, thereby making the dressing suitable to be applied on wounds. In an exemplary case, the multi-layered film exhibits skin regeneration when applied to wounds. In an exemplary case, the multi-layered film generates an electric field stimulating cell proliferation and tissue regeneration.
[0059] In a preferred embodiment chitosan-based organic film with multifunctional properties are disclosed that find importance and will revolutionize the field of biodegradable material. In an embodiment, a renewable and biocompatible biopolymer, with nanoparticle incorporation for color tunability, enhancing its aesthetic appeal and versatility has been disclosed. In an embodiment, the chitosan-based organic films exhibit exceptional mechanical sturdiness and robustness, making them suitable for various applications, including packaging and structural components. In a further embodiment, a unique sodium hydroxide-based crosslinking method ensures improved material integrity and durability, improving upon using other toxic chemicals like glutaraldehyde that have been previously reported for the same purpose. In a further embodiment, these organic films demonstrate the intriguing ability to undergo shape morphing, opening new avenues in adaptive materials design. In a further embodiment, these films exhibit a capacity to generate reactive oxygen species owing to their piezoelectric property, promising potential applications in advanced wound healing and tissue engineering. In a further embodiment, these materials possess inherent antibacterial activity, mitigating microbial growth and providing a sustainable solution in the fight against bacterial contamination.
[0060] Reference is now made to Figure 1A, which is an illustration of an exemplary process or method 100A of preparing an organic based thin film in accordance with an embodiment of the present disclosure. At step 110 a polysaccharide, preferably a non-centre-o-symmetry polysaccharide is taken and dissolved in a solvent forming a first solution. It should be obvious to a person of ordinary skill in the art that though the preferred embodiment related to a non-centre-o-symmetry polysaccharide, other polysaccharides such as centre-o-symmetry polysaccharides may be used, and all such polysaccharides fall within the scope of the present application. In a preferred embodiment, chitosan is chosen as a polysaccharide, as chitosan is a renewable and biocompatible biopolymer. The solvent chosen can dissolve the polysaccharide. At step 120, the polysaccharide dissolved in the solvent is dispensed on a substrate, i.e., the first solution is dispensed on a substrate. In an exemplary case, the substrate may be a petri dish. In an exemplary case of the first solution being prepared in a laboratory, the first solution is dispensed on substrate which includes at least one of synthetic fluoropolymer of tetrafluoroethylene. It should be obvious again to a person of ordinary skill in the art that various other suitable material may be chosen as a substrate based on the polysaccharide and solvent used and all such substrates fall within the scope of the present disclosure. It should also be obvious to a person of ordinary skill that various other substrates may be used instead of a petri dish and all such variation fall within the scope of the present disclosure. In an exemplary case, especially in preparation of such film in larger and bigger quantities, other suitable substrates may be used to form the organic film and all such substrates fall within the scope of the present disclosure. At step 130, the first solution poured on the substrate is allowed to dry under normal temperature and pressure. Drying the first solution on the substrate under normal temperature and pressure forms a multi-layered film, and the thickness associated with the multi-layered film may be variable depending on the amount/volume of first solution dispended and the size of the substrate holding the first solution. In an exemplary case, the thickness of the multi-layered film depends on the volume of the first solution dispensed on the substrate. Once the first solution is dried on the substrate, the multi-layer film formed at step 140 is treated with a base solution such as sodium hydroxide (NaOH), wherein the NaOH is a cross-linking agent.
[0061] Reference is now made to Figure 1B, which is an illustration of an exemplary process or method 100B of preparing an organic based thin film with a mixture of nanoparticles or nano-material composites in accordance with an embodiment of the present disclosure. Similar to the method disclosed with respect to Figure 1A, at step 112 a polysaccharide is dissolved in a solvent forming a first solution. At step 115, the first solution is mixed with a solution of a nano-material composite or nanoparticles forming a mix-solution. In an exemplary case chitosan may be used as the polysaccharide and MoS2 may be used. At step 122, the mix-solution, the first solution mixed with the nanoparticles, is dispensed on a substrate, In an exemplary case, the substrate may be a petri dish. At step 132, the mix solution poured on the substrate (petri dish) is allowed to dry under normal temperature and pressure. Drying the first solution on the substrate under normal temperature and pressure forms a multi-layered film. Once the mix solution is dried on the substrate, the multi-layer film formed at step 142 is treated with a base solution such as sodium hydroxide (NaOH), wherein the NaOH is a cross-linking agent.
[0062] In an exemplary case, both with respect to the organic films produced by the methods as disclosed in Figure 1A and Figure 1B, the polysaccharide chosen is chitosan. In the exemplary case, the multi-layered film formed is treated with a NaOH, wherein NaOH is a cross linking agent. In an exemplary case, the NaOH in addition to creating cross-links in the multi-layered film, also neutralizes any residual solvent in the multi-layered film. In an exemplary case, a concentration of the NaOH can vary in the range from about 50 mM to about 1 M, wherein an extent of degradation of the multi-layered film is determined by the concentration of NaOH. In the exemplary case, the substrate on which the first solution or mixed solution is dispensed is a petri dish made of a synthetic fluoropolymer of tetrafluoroethylene. In an exemplary case, the multi-layered film has a range of transparency from being a completely transparent multi-layered film to a completely translucent multi-layered film. In an exemplary case the transparency of the multi-layered film is associated with varying degrees of light penetration in the multi-layered film. In an exemplary case, the thickness of the multi-layered film is in the range of about 20 µm to about 150µm. It should be obvious to a person skilled in the art that a film with thickness exceeding the range specified may be made and all such films with varying thickness not within the specified range also fall within the scope of the present disclosure.
[0063] In an exemplary case, the multi-layered film treated with NaOH displays no degradation or extremely slow degradation when placed in water or in the presence of water. In an exemplary case, the multi-layered film immediately degrades when deposited in a mild acidic solution or a mild solution of vinegar, and this may be referred to as on-demand degradation. In an exemplary case, the concentration of the acidic medium may vary from about 0.1 % to about 5 %, and the acidic medium facilitates faster degradation of the multi-layered film treated with the basic solution.
[0064] In an exemplary case, the multi-layered film undergoes shape-morphing when deposited in a solution, wherein the solution may be an acidic solution or a basic solution or a pH neutral medium. In an exemplary case, the multi-layered film undergoes deformation at a slow rate exhibiting degradation and/or reverse shape morphing when placed in a solution with a pH = 4. In an exemplary case, the multi-layered film undergoes deformation at a faster rate exhibiting reverse shape morphing and the multi-layered film being intact when placed in a solution of 4 < pH < 9. In an exemplary case, the multi-layered film undergoes bi-directional shape morphing and reverse shape morphing when placed in a solution of pH > 9.
[0065] In an exemplary case, drying the solution (first solution and/or the mix solution) under normal temperature and pressure creates a differential gradient across the multi-layered film. In the exemplary case, the differential gradient leads during the formation of the film results in different sized pores across different layers of the multi-layered film. In an exemplary case, the cross-linked regions in the multi-layered film are sparse on a first side, wherein the first side of the film is proximate with the base (substrate), also referred to as the bottom side of the film, and the cross-linked regions are dense on a second side of the film, the second side is away from the base, also referred to as the top side of the film.
[0066] In an exemplary case, the composition the nano-material composite is in a range from 1mg to 100 mg. In an exemplary case, the nanomaterial composite is soluble under mild acidic conditions and is incorporated into the first solution to form the mix solution. In an exemplary case, the nano-material composite includes at least6 an ore of a transition material or an oxide of a transition material or MoS2 or carbon nanoparticles.
[0067] Reference is now made to Figure 2A, which illustrates an exemplary digital photograph 200A of the organic film prepared in accordance with an embodiment of the present disclosure. As illustrated in Figure 2A, an exemplary multilayered film formed using chitosan and the solvent is illustrated in (i) clearly illustrating that the film is flexible in nature. In the exemplary case, low molecular weight chitosan (hereinafter referred to as CHT) was dissolved in mild acidic conditions and kept for air drying in Teflon petri plates for 7 days to obtain a semi-transparent and highly flexible thin film of 100 µm thickness. As illustrated in exemplary Figure 2, MoS2/CHT films made in the ratios (ii) 1:32, (iii) 1:16 and (iv) 1:8, wherein the ration indicates the weight of MoS2: the weight of CHT. It can be noticed that multi-layered films are flexible in nature and depending on the amount of MoS2 present in the color of the film may be determined. It should be obvious to a person skilled in the art that the use of MoS2 depending on the quantity may produce grey to black film, and other nano-particle used may be instead of MoS2 to produce multi-layered films of different colors, and all such variations fall within the scope of the present disclosure.
[0068] Reference is now made to Figure 2B, which illustrates an exemplary SEM micrograph 200B showing top surface (top panel) and cross-section (bottom panel) of the organic film in accordance with an embodiment of the present disclosure. The scale of the top view is at 2mm and the scale of the cross sectional view illustrated is also 2 mm. In an exemplary case, CHT is a semicrystalline material with numerous intermolecular and intramolecular hydrogen bonds, making it difficult to dissolve in neutral or alkaline conditions. In the exemplary case, Acids protonize the amino groups of CHT and reduce the H-bonding between CHT molecules, leading to the dissolution of chitosan. In an exemplary case, the pristine films have been modified using as-prepared MoS2 nanoflowers to enhance the film's reactive oxygen species (ROS) generating, antibacterial, and cell proliferating abilities, which will be discussed later in the present disclosure. In an exemplary case, since CHT is naturally soluble in water, it was a priority to withstand being subjected to water for days without degradation. In the exemplary case, SEM analysis revealed the non-porous and flat surface of the developed CHT-based organic thin films. In an exemplary case, 1M sodium hydroxide (NaOH) was used as a crosslinking agent. In the exemplary case, SEM analysis revealed the non-porous and flat surface of the developed CHT-based organic thin films.
[0069] Reference is now made to Figure 2C, which is an exemplary XRD spectra 200C of the various organic films and nano-material based organic films prepared in accordance with an embodiment of the present disclosure. The plot shows Intensity (in angstrom units) on the Y axis and the angle (2?) in degrees. Line 210 illustrates the XRD spectra for CHT. Line 220 illustrates the XRD spectra for MoS2/CHT. Line 230 illustrates the XRD spectra for MoS2. In the exemplary case XRD pattern as illustrated of chitosan film exhibited two characteristic broad diffraction peaks at 2? around 9.63 degrees and 20.53 degrees, which may be considered as typical fingerprints of semi-crystalline CHT. The peaks around 9.63 and 20.53 attribute a high degree of crystallinity to the prepared CHT. The as-prepared MoS2 nanoflowers also exhibit characteristic peaks.
[0070] Reference is now made to Figure 2D, which is an exemplary Fourier transform infrared (FTIR) spectroscopy 200D revealed a broad absorption band of the organic films and nano-material composite (hereinafter also referred to as nanoparticle or nano material composites or nano-particle materials) based organic films in accordance with an embodiment of the present disclosure. The plot illustrates the absorption spectrum with wavelength on the X-axis and the transmittance percentage on the Y-axis. As illustrated, shows Fourier transform infrared (FTIR) spectroscopy for MoS2/CHT, CHT, NaOH-CHT and NaOH- MoS2/CHT. The graph revealed a broad absorption band in the 3200 and 3550 cm-1 range due to the overlapping of the hydroxyl group and amino group stretching vibration in both films. The 2920 cm-1 and 2872 cm-1 peaks were due to the –CH2 stretching. In both spectrums, it can be said that the absorption band at 1634 cm-1 belongs to amide I. Peaks at 1535 cm-1 and 1554 cm-1 represent the chitosan carbon chains' N-H (amide II band). In an exemplary case, carbon nanoparticle-incorporated composite films were also prepared. In an exemplary case, nano-material composite added to the multi-layered film increases mechanical strength and flexibility associated with the multi-layered film.
[0071] Reference is now made to Figure 3A, which illustrates an exemplary case of a piezo-electric generator formed using the organic films in accordance with an embodiment of the present disclosure. The multilayered film is prepared using the methods as disclosed in Figure 1A or Figure 1B. The piezo-electric nano-generator includes first sheet of the conducting material 310 is placed on one side of the film 320 (top side) and second conducting sheet 330 is placed on the other side (bottom side) of film 320. The piezo-electric nano-generator is a sandwich of film 320 between two conducting sheets 310, 330. It should be obvious to a person of ordinary skill in the art that instead of conducting sheets, any conducting material in the form of wire or sheets or any other form may be placed above and below the film forming the piezo-electric nano-generator, and all such variations fall within the scope of the present disclosure.
[0072] In an exemplary case, the piezo-electric nano-generator includes sandwiching the flexible multi-layered film 320 between first conducting tape 310 and second conducting tape 330. In the exemplary case, first conducting tape 310 is placed on a top surface of the multi-layered film 320 forming a first electrode and second conducting tape 330 is placed on a bottom surface of the multi-layered film 320 forming a second electrode. In an exemplary case, when a potential difference is generated across the first electrode and the second electrode on application of a pressure on the multi-layered film, due to the flow of electrons between the first electrode and the second electrode, the potential difference is measured as an output voltage across the first electrode and the second electrode. In an exemplary case, first conducting tape 310 and second conducting tape 320 comprises at least one of a metal conductor or a non-metallic conductor. In an exemplary case, first conducting tape 310 and second conducting tape 330 comprises at least one of an organic conductor or an in-organic conductor. In an exemplary case, the piezo-electric nano-generator may be configured to measure output voltages across the electrodes that include a high signal-to-noise ratio. In an exemplary case, the voltage of the normal film is in the range of about 0.9 V. In an exemplary case, the voltage of the nano-material composite based films may be in a range from about 1 Volts to about 3 Volts depending on the concentration of the nano-material composite.
[0073] Reference is now made to Figure 3B, which illustrates an exemplary case of a sensor formed using the organic films in accordance with an embodiment of the present disclosure. The illustration of the sensor is similar to formation of the piezo-electric nano-generator as illustrated in Figure 3A. A multilayer film is first inked, wherein the ink is configured to measure a parameter. In an exemplary case, the measurable parameter is at least one of a pressure and/or a voltage and/or a temperature and/or a wavelength and/or a composition and/or a stress and /or a strain and/or a force and/or a weight and/or a volume and/or a size and/or a force and/or a humidity and/or a flow velocity and/or luminosity, and a specific ink may be used to measure each of these parameters. Once the film 322 is inked with a specific ink that can measure a parameter or with multiple inks that can measure multiple parameters, first conducting material 312 is placed on the top surface of film 322 forming a first electrode and second conducting material 332 is placed on the bottom surface of film 322 forming a second electrode, thereby forming a sensor. In an exemplary case, if film 322 is inked with an ink that monitors pressure, when there is a change in pressure detected, this may be measured as a change in voltage across the electrodes. In a similar manner, it should be obvious to a person of ordinary skill in the art that various other measurable parameters may be monitored, all such measurements made by a sensor in accordance with the embodiments of the present disclosure would fall within the scope of the present disclosure.
[0074] Reference is now made to Figure 3C, which illustrates an exemplary case of a medicated dressing for wounds formed using the organic films in accordance with an embodiment of the present disclosure. In an exemplary case, film 324 may be advantageously used as a base for the medical dressing and one side of film 324 may be coated with a specific medicated layer 314, where the medicated dressing when placed on the wound is configured to heal the wound and grow cells as will be discussed subsequently in the present disclosure.
[0075] Reference is now made to Figure 4A, which illustrates an exemplary case 400A of the organic film in 1% acetic acid solution before and after adding 1M NaOH in accordance with an embodiment of the present disclosure. As illustrated. The CHT multilayered film without NaOH cross linking when placed in 1% acetic acid solution was found to disassociated or degraded almost instantly, whereas the CHT film treated with NaOH, wherein NaOH is a cross linking agent, when placed in 1% acetic acid solution did not show a degradation of the film or extremely slow degradation of the NaOH treated film. A conclusion therefore may be drawn that the NaOH treated film are more stable and do not degrade easily.
[0076] Reference is now made to Figure 4B, which illustrates an exemplary case of comparing Glutaraldehyde and NaOH cross-linked films before and after immersion in deionized (DI) water for 10 min, where the scale is about 10 mm, in accordance with an embodiment of the present disclosure. In an exemplary case, Glutaraldehyde may be used as a cross linking agent for the film instead of NaOH. A disadvantage is that glutaraldehyde is toxic in nature and not environmental friendly, which leads to several other issues of manufacturing plastics for example using the film and cross-linking with glutaraldehyde. In the exemplary case, further the same films without moisture content also shows a slight deformation in when glutaraldehyde than a more stable form when the film is treated with NaOH. When the film is having moisture content, the film treated with glutaraldehyde as the cross linking agent almost instantly degrades compared to the film treated with NaOH which does not degrade and shows better stability.
[0077] Reference is now made to Figure 5A, which illustrates an exemplary case contact angle measurement of CHT, MoS2/CHT, and NaOH-CHT films in accordance with an embodiment of the present disclosure. In the exemplary case, contact angle measurements conducted to evaluate the changes in the surface properties of the film before and after crosslinking with NaOH are illustrated. In the exemplary case, the CHT film exhibited an angle measurement of less than 90°, indicating its hydrophilic nature, whereas in contrast, the MoS2/CHT films displayed an angle greater than 90°, suggesting their hydrophobic characteristics. In the exemplary case, the NaOH-CHT films exhibited the smallest contact angle, indicating the highest level of hydrophilicity among the three films. Thus conclusively, NaOH treated films showed better hydrophilicity compared to the non-NaOH treated CST film and the MoS2-CHT film.
[0078] Reference is now made to Figure 5B, which illustrates an exemplary case of an indentation study of CHT, MoS2/CHT, NaOH-CHT and NaOH-MoS2/CHT films in accordance with an embodiment of the present disclosure. In an exemplary case the surface stiffness of the films using force-distance spectroscopy (FDS) is illustrated in Figure 5B. The CHT films had the lowest Young's modulus (160 kPa), indicating lower mechanical strength and higher elasticity, and therefore these films have a propensity to break more easily. On the other hand, NaOH-MoS2/CHT films demonstrated the highest Young's modulus (190 kPa), making them strong and most durable among the four samples that were analyzed. In the exemplary case, the incorporation of MoS2 significantly enhances the mechanical strength of CHT films, as demonstrated by their FDS characterization, where they exhibited Young's modulus of 175 kPa, which still surpasses the Young’s modulus of the CHT film.
[0079] Reference is now made to Figure 5C, which illustrates an exemplary case of DMA studies showing Stress versus strain curve in accordance with an embodiment of the present disclosure. The mechanical properties and behavior of the films were further quantified through dynamic mechanical analysis (DMA. The stress versus strain curve displayed Young’s modulus of the different films, with the CHT film possessing the least ability to withstand stress and breaking off at a low strain value (~10 %), while that of the NaOH-CHT film went up to as high as 125%. The graph also demonstrated the mechanical strength imparted to CHT film by incorporating MoS2 nanoflowers, as the MoS2/CHT film was able to withstand a stress of nearly 25%, compared to the low value of pristine CHT film.
[0080] Reference is now made to Figure 5D, which illustrates an exemplary case of Force versus Displacement behavior of the films in accordance with an embodiment of the present disclosure. From the displacement versus force curve, the pristine CHT film is noticed to be the most flexible of all the films, as it underwent a displacement of 400 cm (maximum) but had a breaking point earlier than all other films. On the contrary, the NaOH-CHT film could tolerate the maximum force (18N) without breaking. This indicates the robustness imparted to the CHT film by NaOH crosslinking while forming the NaOH-CST crosslinked film.
[0081] Reference is now made to Figure 5E, which illustrates an exemplary case Expansion in the area over 24 hours after immersing in DI water in accordance with an embodiment of the present disclosure. The films CHT and NaOH-CST treated films were immersion in DI water to investigate the degradation kinetics of both the pristine and cross-linked films. In an exemplary case, the initial weight of the films before immersion (i.e., 66 mg) were measured and compared them to their weight after 10 min, both for uncross-linked and cross-linked conditions. Remarkably, in the exemplary case, a ?21% reduction (45 mg) in weight for the uncross-linked film after 24 hours was observed, whereas the cross-linked film experienced a much smaller 3.5% reduction (63.5 mg) in weight.
[0082] Reference is now made to Figure 5F, which illustrates an exemplary case Expansion in the area over 24 hours after immersing in DI water in accordance with an embodiment of the present disclosure. In the exemplary case, the area expansion caused by swelling was measured from the CHT and NaOH-CHT cross linked films. In the exemplary case, the uncross-linked film expanded by a significant 900%, while the cross-linked film only expanded by a modest 100%. In the exemplary case, these differential swelling rates may be attributed to the pore size of the two films, where crosslinking the CHT film with NaOH reduces the film's pore size, limiting the amount of water that can penetrate into the film and resulting in a less pronounced expansion.
[0083] Reference is now made to Figure 6A, which illustrates an exemplary case of Oscilloscope measurements for gentle tapping on an organic film in accordance with an embodiment of the present disclosure.
[0084] Reference is now made to Figure 6B, which illustrates an exemplary case of Oscilloscope measurements for vigorous tapping on CHT and MoS2/CHT (varying concentrations) films in accordance with an embodiment of the present disclosure.
[0085] Reference is now made to Figure 6C, which illustrates an exemplary case of Comparative piezoelectric measurement in accordance with an embodiment of the present disclosure. With reference to Figure 6A, Figure 6B and Figure 6C, and in referencing Figure 3A, oscilloscope measurements for gentle tapping on CHT film, vigorous tapping on CHT and MoS2/CHT (varying concentrations) films, and Comparative piezoelectric measurement are illustrated. As illustrated, a piezoelectric nanogenerator (also referred to as PENG) may be constructed by sandwiching a CHT-based thin film between two conducting tapes, wherein the conducting tapes from the top electrode and the bottom electrode. In an exemplary case, aluminium (Al) tape may be used to form the electrodes, but it should be obvious to a person of ordinary skill in the art that any conducting material may be used to form the electrodes, and all such conducting materials fall within the scope of the present disclosure. In the exemplary case, the output voltage was recorded using a digital UNI-T oscilloscope. In an exemplary case, PENG terminals were connected with an oscilloscope channel to complete the circuit. Figure 6A illustrates the output signal under gentle repetitive tapping (with gloves on) on the device, while Figure 6B illustrates the output signal under vigorous tapping, showing the output voltage in milli volts against time. As illustrated in Figure 6A and Figure 6B, tapping-induced prominent spikes in the generated voltage with a very high signal-to-noise ratio. In the exemplary case, systematic measurement of the piezoelectric signal from CHT/MoS2 films, where MoS2 has differing weights 0 mg, 10 mg, 25 mg, and 40 mg under different applied pressures is summarized in Figure 6a and Figure 6B. In the exemplary case, an electron flow is established between the two electrodes upon applying external pressure onto the sandwiched PENG device, which creates a potential difference. In the exemplary case, loading an amount of MoS2 as indicated previously in terms of the weight in CHT thin films substantially influenced the output voltage magnitude. In the exemplary cases, PENG devices fabricated with bare CHT films showed ?0.9V, while CHT/MoS2-based PENG devices generated 1.3V (10 mg), 1.4V (25 mg), and 1.7V (40 mg) signals under the same condition. In the exemplary case, piezoelectric response was enhanced 2-fold or more under rigorous tapping illustrated in Figure 6B as compared to gentle tapping in illustrated Figure 6A. In the exemplary case, this may be attributed to the fact that single-atomic-layer MoS2 possesses piezoelectric characteristics due to the lattice distortion induced by strain and the consequent polarization of ion charges. In the exemplary case, it may be important to note that two-dimensional piezoelectricity manifests only when the number of layers is odd due to the disruption of inversion symmetry.
[0086] Figure 7A is an exemplary case of Bacterial assay displaying CFU/ml after treatment of E. coli with MoS2/CHT films under white light in accordance with an embodiment of the present disclosure.
[0087] Figure 7B is an exemplary case of Digital images of grown colonies that were obtained after 30 min of illumination with white light on MoS2/CHT films in accordance with an embodiment of the present disclosure.
[0088] With reference to Figures 7A and 7B, In an exemplary case, antibacterial studies showed that CHT or MoS2/CHT film inhibited bacterial growth due to its synergistic piezoelectric and photo responsive activity. In an exemplary case, the photocatalytic activity of the CHT film and the photocatalytic activity of MoS2/CHT may be demonstrated through several assays. In the exemplary case, in these assays, the reactants involved may be transformed into their respective by-products as they reacted with the reactive oxygen species (ROS) generated by the film. In the exemplary case, to evaluate the superoxide-radical generating capacity of the films, an XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide)assay was considered. In an exemplary case, the groups with films were compared under two conditions first at rest and second under vortexing. In the exemplary case, significantly higher amounts of the formazan by-product of XTT were produced in the vortexed groups, as indicated by the absorbance values, compared to the groups at rest. In the exemplary case, additionally, the photocatalytic capability of MoS2 was assessed. In the exemplary case, one group was subjected to white light exposure along with vortexing, and it may be observed that this specific group exhibited higher absorbance compared to the group subjected to vortexing alone. In the exemplary case, this observation underscores the synergistic photocatalytic and photocatalytic properties of the MoS2/CHT film. In an exemplary case, an Amplex Red assay was used out to determine the amount of hydrogen peroxide (H2O2) catalyzed by the films into hydroxyl radicals. In the exemplary case, the assay was carried out per the same protocol as the XTT assay. In the exemplary case, the fluorescence of the by-product was measured to detect the amount of OH radicals generated. In this exemplary case, the MoS2/CHT films also displayed higher fluorescence than pristine CHT films, indicating their higher photocatalytic potential.
[0089] Figure 8A is an exemplary case of Biocompatibility assay of CHT and MoS2/CHT films with NIH 3T3 cells for 24h and 48 h in accordance with an embodiment of the present disclosure.
[0090] Figure 8B is an exemplary case of Cellular viability of NIH 3T3 cells onto CHT film for 24 and 48 hours in accordance with an embodiment of the present disclosure.
[0091] Figure 8C is an exemplary case of Cell proliferation assay for CHT and MoS2/CHT films with and without ultra-sonication for 10 min (1 MHz) in accordance with an embodiment of the present disclosure.
[0092] .Figure 8D is an exemplary case of Time-dependent ultrasound-mediated cell proliferation assay for CHT film on NIH 3T3 cells in accordance with an embodiment of the present disclosure.
[0093] Figure 8E is an exemplary case illustrating Live/dead analysis of NIH 3T3 cells by staining with calcein (100 µm ) in accordance with an embodiment of the present disclosure.
[0094] Figure 8F is an exemplary case illustratingDAPI/Actin staining images of NIH 3T3 cells adhered onto CHT films (100 µm ) in accordance with an embodiment of the present disclosure.
[0095] With reference to Figures 9A – 9F, in the exemplary case, after confirming the biocompatibility of the films an ultrasound-mediated cell proliferation assay using NIH 3T3 mouse fibroblast cells was conducted. In the exemplary case, the results of the assay revealed a remarkable increase in cell proliferation (~70%) in the test group (CHT + US for 10 minutes) compared to the control group (~5%). In the exemplary case, this outcome provides compelling evidence that the piezoelectric potential is pivotal in driving cell proliferation and suggests its potential application in tissue regeneration. In an exemplary case, considering a time-dependent trend, where cells exposed to ultrasound for 1 and 5 minutes in the presence of the CHT film exhibited lower proliferation rates (5% and 30%, respectively). In an exemplary case, this observation suggests that prolonged film stimulation leads to higher voltage generation, highlighting the potential for fine-tuning and optimizing this process for specific applications.
[0096] In an exemplary case, in addition, CHT-based organic films promote cell adherence and fibroblast proliferation under ultrasound stimulation therefore, such films can be a potential substitute for skin tissue/graft as illustrated in Figure 9D. In a exemplary case, Adhered cells exhibited consistent and healthy morphology as illustrated in Figure 9E and Figure 9F.
[0097] Figure 9 is an exemplary illustration of the Shapes of CHT films and MoS2/CHT films before and after immersing in DI water for about 1 min, where AR is the aspect ratio in accordance with an embodiment of the present disclosure. In an exemplary case, another unique feature that the films exhibit is shape morphing, wherein upon placing the films in DI water, they undergo a rapid distortion in shape and form unique morphologies. In an exemplary case, a thin strip transforms into a helical structure, while a square transforms into a tube. In a further exemplary case, the film for different aspect ratios is also indicated indicating the folding of the film or morphing of the shape of the film.
[0098] Although the present disclosure has been described with reference to several preferred embodiments, it should be understood that the present disclosure is not limited to the preferred embodiments disclosed here. Embodiments of the present disclosure are intended to cover various modifications and equivalent arrangements within the spirit and scope of the appended claims. Although the foregoing disclosure has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practised within the scope of the appended claims. Examples of the present disclosure have been described in language specific to structural features and/or methods. It should be noted that there are many alternative ways of implementing both the process and apparatus of the present invention. Accordingly, embodiments of the present disclosure are to be considered illustrative and not restrictive, and the invention is not to be limited to the details given herein but may be modified within the scope and equivalents of the appended claims. It should be understood that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed and explained as examples of the present disclosure.

, C , Claims:We Claim:
1. A method for producing a multi-layered film, the method comprising:
- dissolving a non-centrosymmetric polysaccharide in a solvent, wherein the solvent is an acidic medium, forming a first solution;
- dispensing the first solution onto a base; and
- drying the first solution on the base under normal temperature and pressure to produce a multi-layered film.

2. The method as claimed in claim 1, the method comprising:
- treating the multi-layered film with a basic solution, wherein
- the basic solution is a cross linking agent, forming cross links in the multi-layered film; and
- the basic solution neutralizes any residual solvent in the multi-layered film.

3. The method as claimed in claim 2, wherein the basic solution comprises a pH = 10.

4. The method as claimed in claim 2, wherein a concentration of the basic solution varies in the range from about 50 mM to 1 M, and wherein the concentration of the basic solution determines an extent of degradation of the film.

5. The method as claimed in claim 1, wherein the multi-layered film transparency ranges from being a completely transparent multi-layered film to a translucent multi-layered film, wherein the transparency is dependent on a concentration of the first solution and a concentration of the basic solution.

6. The method as claimed in claim 1, wherein a thickness of the multi-layered film is in the range of about 20 µm to about 150µm.

7. The method as claimed in claim 2, wherein:
- the multi-layered film treated with the basic solution displays no degradation or extremely slow degradation when placed in water; and
- the multi-layered film not treated with the basic solution degrades when deposited in water.

8. The method as claimed in claim 2, wherein the multi-layered film when deposited in a mild acidic solution or a mild solution of vinegar facilitates faster degradation, wherein a concentration of the mild acidic medium varies from about 0.1 % to about 5 %.

9. The method as claimed in claim 1, wherein the multi-layered film undergoes shape-morphing when deposited in a solution, wherein the solution may be an acidic solution or a basic solution or a pH neutral solution.

10. The method as claimed in claim 9, wherein the rate of shape-morphing is slower in the acidic solution or the basic solution compared to the pH neutral solution.

11. The method as claimed in claim 10, wherein the multi-layered film undergoes:
- deformation at a slow rate exhibiting degradation and/or reverse shape morphing when placed in a solution with a pH = 4; deformation at a faster rate exhibiting reverse shape morphing and the multi-layered film being intact when placed in a solution of 4 < pH < 9; and
- undergoes bi-directional shape morphing and reverse shape morphing when placed in a solution of pH > 9.

12. The method as claimed in claim 1, wherein drying the first solution under standard conditions creates a differential gradient across the multi-layered film, wherein the differential gradient leads to formation of different sized pores across different layers of the multi-layered film.

13. The method as claimed in claim 2, wherein the cross-linked regions in the multi-layered film are sparse on a first side, wherein the first side of the film is proximate with the base and the cross-linked regions are dense on a second side of the film wherein the second side is away from the base.

14. The method as claimed in claim 13, wherein pores on the first side are larger in size compared to pores on the second side, wherein a pore size on the first side are large due to faster drying time and a pore size on the second side are smaller due to slower drying time.

15. The method as claimed in claim 1, the method comprising:
- adding a nano-material composite to the first solution, wherein the nano-particle composite dissolves in the first solution forming a mix-solution;
- dispensing the mix-solution onto a base;
- drying the solvent from the mix-solution at under normal temperature and pressure to obtain a multi-layered film.

16. The method as claimed in claim 15, wherein the nano-material composite comprises an ore of a transition material or an oxide of a transition material or MoS2 or carbon nanoparticles, and a composition the nano-material composite in a range from 1mg to 100 mg.

17. The method as claimed in claim 16, wherein the nanomaterial composite soluble under mild acidic conditions is incorporated into the first solution.

18. A method of forming a piezoelectric nanogenerator, the method comprising:
- sandwiching a flexible multi-layered film between a first conducting tape and a second conducting tape, wherein the first conducting tape is on a top surface of the multi-layered film forming a first electrode and the second conducting tape is on a bottom surface of the multi-layered film forming a second electrode, and wherein the flexible multi-layered film formed by the method as claimed in any of the claims 1 to 17.

19. The method as claimed in claim 18, wherein a potential difference is generated across the first electrode and the second electrode on application of a pressure on the multi-layered film, wherein the potential difference is due to the flow of electrons between the first electrode and the second electrode, and the potential difference is measured as an output voltage across the first electrode and the second electrode.

20. The method as claimed in claim 18, wherein the first conducting tape and the second conducting tape comprises at least one of a metal conductor or a non-metallic conductor, and wherein the first conducting tape and the second conducting tape comprises at least one of an organic conductor or an in-organic conductor.

21. The method as claimed in claim 18, wherein addition of a nano-material composite to the multi-layered film increases a mechanical strength and flexibility associated with the multi-layered film and exhibits a higher electrical potential.

22. The method as claimed in claim 21, wherein the voltage of the multi-layered film is in the range of about 0.8 V to about 1.2V.

23. The method as claimed in claim 21, wherein the voltage of a multi-layered film without any nano-particle composite is about 0.9 V and the voltage of the multi-layered film with the nano-material composite is in a range from about 1 Volts to about 3 Volts, wherein the voltage is proportional to the concentration of the nano-material composite in the multi-layered film.

24. A device and/or a system formed by the method as claimed in any of the claims 1 to 23.

25. A sensor formed by the method as claimed in any of the claims 1 to 23.

26. The sensor as claimed in claim 25, wherein the multi-layered film is provided with an ink, and the ink is sensitive to a measurable parameter and the measurable parameter is at least one of a pressure and/or a voltage and/or a temperature and/or a wavelength and/or a composition and/or a stress and /or a strain and/or a force and/or a weight and/or a volume and/or a size and/or a force and/or a humidity and/or a flow velocity and/or luminosity.

27. The sensor as claimed in claim 25, the sensor configured to measure dynamic changes in pressure and/or acceleration and/or temperature and/or strain and/or force.

28. A plastic formed by the method as claimed in any of the claims 1 to 23.

29. A plastic as claimed in claim 28, wherein a color of the plastic is dependent on the nano-particle composite.

30. A biocompatible dressing formed by the method as claimed in any of the claims 1 to 23.

31. The dressing as claimed in claim 30, wherein the dressing exhibits photocatalytic activity wherein bacterial activity was reduced, thereby making the dressing suitable to be applied on wounds.

32. The dressing as claimed in claim 31, wherein the multi-layered film exhibits skin regeneration when applied to wounds.

33. The dressing as claimed in claim 32, wherein the multi-layered film generates an electric field stimulating cell proliferation and tissue regeneration.

Dated this 13th day of February 2024
Indian Institute of Science
By their Agent & Attorney

(Dr. Eric W B Dias)
of Khaitan & Co
Reg No IN/PA-1058