Description:Form 2

THE PATENT ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)

“A PROCESS FOR SYNTHESIZING GRAPHENE QUANTUM DOTS USING AGRICULTURAL WASTE BAGASSE”

in the name of KOTHARI SUGARS AND CHEMICALS LTD an Indian national having address at, KOTHARI BUILDINGS, 115 MAHATMA GANDHI ROAD, NUNGAMBAKKAM, CHENNAI, CHENNAI – 600034, TAMIL NADU, INDIA.

The following specification particularly describes the invention and the manner in which it is to be performed.

SOURCE AND GEOGRAPHICAL ORIGIN OF THE BIOLOGICAL MATERIAL:

SL.
NO COMMON NAME SCIENTIFIC NAME PART OF BIOLOGICAL SOURCES SOURCE OF ACCESS DETAILS OF GEOGRAPHICAL LOCATION
1. Sugarcane Saccharum officinarum Stalk-Bagasse Trader (i)Name of the trader:
Kothari sugars and chemicals Ltd.

(ii) Contact details: Sathamangalam village,
Vettriyur Post
Ariyalur District – 621707
Tamil Nadu,
India.

FIELD OF THE INVENTION:

The present invention generally relates to a process of preparation of graphene quantum dots. More particularly, the present invention relates to a process of synthesis of graphene quantum dots from agricultural waste bagasse and product thereof.

BACKGROUND OF THE INVENTION:

Graphene quantum dots (GQDs) are single atom thick sheets of graphene that generally have no dimension greater than 100 nanometers (nm). GQDs can be used in a wide variety of applications ranging from electronics, optoelectronics and electromagnetics. The electrical, magnetic, optical and chemical properties of GQDs are governed by their size and edge crystallography. Compared to graphene, GQDs exhibit stronger photoluminescence useful in bio-imaging, biosensing and light-emitting diodes.

GQDs are synthesized using methods such as liquid exfoliation, electrochemical techniques, soft templates and metal-catalyzed processes.

There are reports available in the state of art revealing the existence of methods for preparing graphene quantum dots.

US20150284318A1 discloses a method for forming a graphene quantum dot product includes adding an organic starting material to a vessel and heating the organic starting material to a temperature within 20° C. of the organic starting material's boiling temperature for a time no longer than ten minutes to form graphene quantum dots. A method for sensing a graphene quantum dot includes forming a graphene quantum dot, exciting the graphene quantum dot with light having a first wavelength, measuring light emitted by the excited graphene quantum dot at a second wavelength different from the first wavelength. A graphene quantum dot includes carbon atoms and nitrogen atoms where the nitrogen atoms are present within the graphene quantum dot at a level between 6.0% and 11.0% of a level of carbon atoms present in the graphene quantum dot.

US9505623B1 discloses a method of making graphene quantum dots (GQDs) comprising: combining a graphene source with a strong oxidizing mixture to form a combination; and heating the combination to an elevated temperature with respect to room temperature to produce the GQDs, wherein the strong oxidizing mixture comprises an oxidizing agent selected from the group consisting of a permanganate, a hexafluoromanganate, a persulfate, a chromate, Fenton's reagent, an oxidizing acid, and a combination thereof.

US20210316995A1 discloses a method of preparing graphene quantum dots by intercalation of graphite nanoparticles and continuous exfoliation in an aqueous solution. The preparation method has a short process time and uses graphite nanoparticles of several nm as a reactant. Thus, graphene quantum dots prepared by the preparation method are uniform in size and shape with minimized defects and improved electrical properties.

The above disclosed methods have their advantages. Despite their efficiency, a major problem involves the elimination of by-products like inorganic salts and acids. Moreover, Scaling up these methods for large-scale production while preserving material crystalline presents a challenge. Further they are time consuming or complicated and use require harsh chemicals which include the use of strong acids and alkali.

Thus, there exists a need in the state of art to develop a simple, cost-efficient and eco-friendly process for preparing graphene quantum dots.

Hence, an attempt has been made to develop a cost-efficient and eco-friendly process for synthesis of graphene quantum dots employing agricultural waste bagasse overcoming the above said drawbacks.
OBJECT OF THE INVENTION:

The main object of the present invention is to develop a cost-efficient and eco-friendly process for synthesis of graphene quantum dots.

Another object of the present invention is to develop a process for synthesis of graphene quantum dots employing agricultural waste bagasse.

Yet another object of the present invention is to characterize the prepared bio-compatible graphene quantum dots.

Further object of the present invention is to utilize the developed graphene quantum dots in bio-imaging, biosensors, drug delivery and nanocarrier.

BRIEF DESCRIPTION OF THE DRAWINGS:

Figure 1 depicts flow chart of preparation of Graphene quantum dots of the present invention.

Figure 2 depicts Schematic representation of Graphene oxide synthesis process.

Figure 3 depicts Schematic representation of GQDs synthesis process.

Figure 4 UV-visible spectrum of GQD of the present invention.

Figure 5 represents HR-TEM images of GQDs
(a) scale bar 20nm. Inset of (a) GQDs in 2nm scale
(b) scale bar of 50nm.
SUMMARY OF THE INVENTION:

The present invention discloses a process of synthesis of graphene quantum dots from agricultural waste bagasse. The process of the present invention comprises of following steps;
a. mixing dried and fine powdered Sugarcane bagasse and Ferrocene followed by heating to form graphene oxide;
b. subjecting the graphene oxide in deionized water to hydrothermal treatment followed by filtration and dialysis to obtain graphene quantum dots.
The present invention also discloses a graphene quantum dots prepared by the process as described above.

DETAILED DESCRIPTION OF THE INVENTION:

The present invention discloses a process of synthesis of graphene quantum dots from agricultural waste bagasse and product thereof.

The process of the present invention comprises of following steps; dried and fine powdered Sugarcane bagasse and Ferrocene is mixed and heated to form graphene oxide. The graphene oxide is then subjected to hydrothermal treatment in deionized water and filtered and subjected to dialysis to obtain graphene quantum dots (Figure 1, 2 &3).

The synthesized graphene quantum dots were then subjected to characterization using UV-Visible Spectroscopy and High-Resolution Transmission Electron Microscopy (HR-TEM).

The UV-Vis spectrum of the obtained GQDs shows an absorption peak at 250 nm corresponds to p-p* transition of the aromatic sp2 domains(Figure 4).

High-Resolution Transmission Electron Microscopy (HR-TEM) images of GQDs exhibited a quasi-spherical shape with size distribution between 3 to 7 nm. The inset of fig 5(a) indicates the high crystallinity of GQDs with a lattice parameter of 0.26nm.

Advantages of the present invention:

• Eco-friendly
• Non-toxic: No release of toxic gases
• Cost-effective
• Reducing waste and optimizing resource efficiency
• Overcomes limitations related to toxic by-products, low yield and imprecise control over GQDs morphology.
• Economically viable making them suitable for biomedical applications

Thus, from the above it is concluded that the prepared graphene quantum dots by the process of the present invention be a suitable candidate for use in biomedical applications as the process is simple and cost-effective than the existing ones.

In one of the preferred embodiments, the present invention shall disclose a process of synthesis of graphene quantum dots from agricultural waste bagasse. The process of the present invention comprises of following steps;

a. mixing dried and fine powdered Sugarcane bagasse and Ferrocene followed by heating to form graphene oxide;
b. subjecting the graphene oxide in deionized water to hydrothermal treatment followed by filtration and dialysis to obtain graphene quantum dots.

In another preferred embodiment, the present invention shall disclose a graphene quantum dots prepared by the process as described above.

In yet another preferred embodiment, the present invention shall disclose a process of synthesis of graphene quantum dots from agricultural waste bagasse. The process of the present invention comprises of following steps;

a. mixing dried and fine powdered Sugarcane bagasse and Ferrocene in a ratio of 5:1 followed by heating in a muffle furnace at 300°C for 10 minutes to form graphene oxide;
b. subjecting the said graphene oxide in deionized water to hydrothermal treatment at 200oC for 2 hours followed by filtration and dialysis for 1 day to obtain graphene quantum dots.

In further preferred embodiment, the present invention shall disclose a graphene quantum dots prepared by the process as described above.

Working example:

Process of synthesis of graphene quantum dots from agricultural waste bagasse.
Dried and fine powdered of Sugarcane bagasse and Ferrocene in a ratio of 5:1 were mixed and heated in a muffle furnace at 300°C for 10 minutes to form graphene oxide. The graphene oxide was then subjected to hydrothermal treatment in deionized water at 200oC for 2 hours and filtered and then dialyzed for 1 day to obtain graphene quantum dots.
Although the invention has now been described in terms of certain preferred embodiments and exemplified with respect thereto, one skilled in the art can readily appreciate that various modifications, changes, omissions, and substitutions may be made without departing from the scope of the following claims.

, Claims:WE CLAIM:

1. A process of synthesis of graphene quantum dots from agricultural waste bagasse, comprises of following steps;
a. mixing dried and fine powdered Sugarcane bagasse and Ferrocene followed by heating to form graphene oxide;
b. subjecting the said graphene oxide in deionized water to hydrothermal treatment followed by filtration and dialysis to obtain graphene quantum dots.

2. A graphene quantum dots prepared by the process as claimed in claim 1.

3. A process of synthesis of graphene quantum dots from agricultural waste bagasse comprises of following steps;
a. mixing dried and fine powdered Sugarcane bagasse and Ferrocene in a ratio of 5:1 followed by heating in a muffle furnace at 300°C for 10 minutes to form graphene oxide;
b. subjecting the said graphene oxide in deionized water to hydrothermal treatment at 200oC for 2 hours followed by filtration and dialysis for 1 day to obtain graphene quantum dots.

4. A graphene quantum dots prepared by the process as claimed in claim 3.

Dated this 08th day of FEB 2024

For KOTHARI SUGARS AND CHEMICALS LTD
By its Patent Agent
Dr.B.Deepa
IN/PA 1477