Description:FIELD OF INVENTION
[001] The present invention relates to the field of Inorganic quantum dots for hybrid organic solar cells (OSCs). More specifically, inorganic quantum dots were synthesized by in-situ synthesis in the polymer matrix for hybrid OSCs devices.

Definitions of Terms and Phrases
[002] It may be noted that the abbreviations are not necessarily used commonly. For the facilitation of drafting, several abbreviations may be formulated strictly for this specification describing the present invention.

OPV: Organic Photo Voltaic
OSC(s): Organic Solar Cell(s)
BHJ: Bulk Hetero Junction
HTL(s): Hole Transport Layer(s)
ITO: Indium Tin Oxide
QD’s: Quantum Dots
CNT: Carbon nanotube
P3HT: Poly-3-hexylthiophene
CdS: Cadmium Sulphide
TCB: Trichlorobenzene
TOP: Trioctylphosphine
MoO3: Molybdenum oxide

[003] It may be noted that as per the requirement of invention disclosure, terms or phrases are used in several combination.

BACKGROUND AND PRIOR ARTS OF INVENTION
[004] Organic solar cell (OSCs) devices have drawn great scientific attention over the last few years, due to its potential to produce flexible, light weight, low cost solar cells using organic materials. However, the power conversion efficiency achieved for these systems is low for extensive implementation of the technology. Among the various photovoltaic technologies, organic/polymer photovoltaics based on solution processed bulk-heterojunction (BHJ) concept gained significant attention due to the use of inexpensive light-weight materials, exhibiting high mechanical flexibility and compatibility with low temperature roll-to-roll manufacturing techniques. Improvement in OPVs efficiencies by various ways such as synthesis of new materials, optimization of morphology of active layer and using advanced device geometry such as multi-junction structures, ternary blend near-IR sensitization and organic-inorganic hybrid systems have been the scope of many researches during last decades. After that the research focuses on the semiconductor nanocrystals or quantum dots. Semiconducting quantum dots nanostructures have great potential for photovoltaic applications due to high absorption coefficient, tunable band gap which is size dependent, multiple exciton generation with single photon absorption, tunable energy levels, slow exciton relaxation and low cost. Despite these conceptual advantages, QD’s based organic solar cells have demonstrated poor device performances as a result of hopping charge transport among discrete QD’s particles. Besides, QD’s phase separate from their organic matrix, thus developing a bicontinuous network is difficult. Improvement in the charge separation and charge transport can be achieved via a hybridization of QD’s with one dimensional electrically conductive nanostructure materials like CNT.

[005] In this way, CNT particles would behave as support for the light harvesting semiconductor QD’s, leading to the enhancement of the exciton dissociation and charge transport towards the corresponding electrodes. Unique optical and electrical properties of CNT as well as its wide electrochemical stability window and high surface area render CNT as an excellent for OSCs. As a consequence of such synergistic effect, BHJ solar cells containing CNT/QD nanohybrid have attracted great attentions. To enhance the charge generation and transport many attempts have been reported on the QD loaded CNT sensitized organic solar cells. High efficiency of these nanohybrid based OSCs is attributed to the enhanced charge separation at the QD-polymer and QD-CNT interfaces and increased charge transportation within the active layer due to high charge carrier mobility through the interconnected CNT clusters.

[006] In present work, we discuss the power conversion efficiency of the hybrid (organic-inorganic) solar cells enhanced by the in-situ synthesis of the PbSe quantum dots in the P3HT polymer matrix, used as an active layer material for OSCs fabrication. Following are the works done so far in the field of In-situ synthesis of Inorganic quantum dots in polymer matrix for organic solar cells.

[007] US9099663B1 disclosed a solar cell and method of making. The solar cell includes an acceptor layer a donor layer treated with a first quantum dot (QD) ligand and a blocking layer treated with a second, different, QD ligand. The acceptor layer has an acceptor layer valence band and an acceptor layer conduction band. The donor layer has a donor layer valence band and a donor layer conduction band, the donor layer valence band is higher than the acceptor layer valence band, the donor layer conduction band is higher than the acceptor layer conduction band. The blocking layer least partially blocks electron flow in at least one direction, the blocking layer having a blocking layer valence band and a blocking layer conduction band, the blocking layer valence band is higher than the donor layer valence band, the blocking layer conduction band is higher than the donor layer conduction band. Solution processing is a promising route for the realization of low-cost, large-area, flexible, and light-weight photovoltaic devices with short energy payback time and high specific power. However, solar cells based on solution-processed organic, inorganic, and hybrid materials reported thus far generally suffer from poor air stability, require an inert-atmosphere processing environment, or necessitate high temperature processing, all of which increase manufacturing complexities and costs. Simultaneously fulfilling the goals of high efficiency, low-temperature fabrication conditions, and good atmospheric stability remains a major technical challenge.

[008] US9324562B1 relates to the generation of QD and/or NC materials. In various aspects, the QDs and/ or NCs in the materials are put into contact with a metal halide solution, with the contacting occurring after the QDs and/ or NCs have been synthesized. Without wishing to be bound by any theory, it is believed that the metal halide solution displaces native ligands present in the QDs/NCs from the manufacturing process. In that respect, the native ligand is replaced with one or more of the ions present in the metal halide solution, by ligand exchange. It is also believed that the ligand exchange, and thus the removal of the native ligands, increases the stability of the QDs and/or NCs. Therefore, in various aspects, the present disclosure provides methods of treating a nanocrystal material, the methods include contacting one or more nanocrystals with a solution containing metal ions and halogen ions, wherein one or more of the ions displaces ligands from the nanocrystals. The NCs and/or QDs do not need to be deposited on a substrate. In some embodiments, the NCs and QDs are neat and/or pure in solution. In some embodiments, the NCs and/or QDs are deposited on a substrate. The methods disclosed herein relate to the treatment of nanocrystals generally, quantum dots being one example of a nanocrystal, and can be utilized in any method in which NCs and/or QDs are used or prepared and/or in the preparation of any device that utilizes NCs and/or QDs in any way. Non-limiting examples of QD/NC materials and applications in which the methods provided by the present disclosure can be utilized include the manufacture of devices such as light-emitting diode (LED) displays, transistors, diode lasers and solar cells. In addition, the disclosed methods may be utilized to treat QDs and/or NCs used in medical imaging, bio-imaging, quantum computing, QD display, and/or photocatalysis.

[009] US20060243959A1 provides of a three-dimensional bicontinuous heterostructure, a method of producing same, and the application of this structure towards the realization of photodetecting and photovoltaic devices working in the visible and the near-infrared. The three-dimensional bicontinuous heterostructure includes two interpenetrating layers which are spatially continuous; they are including only protrusions or peninsulas, and no islands. The method of producing the three-dimensional bicontinuous heterostructure relies on forming an essentially planar continuous bottom layer of a first material; forming a layer of this first material on top of the bottom layer which is textured to produce protrusions for subsequent interpenetration with a second material, coating this second material onto this structure; and forming a final coating with the second material that ensures that only the second material is contacted by subsequent layer. One of the materials includes visible and/or infrared-absorbing semiconducting quantum dot nanoparticles, and one of materials is a hole conductor and the other is an electron conductor.

[0010] US 2010/01334.18 A1 discloses the Optical and optoelectronic devices and methods of making same. In one aspect, an optical device includes an integrated circuit an array of conductive regions; and an optically sensitive material over at least a portion of the integrated circuit and in electrical communication with at least one conductive region of the array of conductive regions. Under another aspect, a method of forming a nanocrystalline film includes fabricating a plurality of nanocrystals having a plurality of first ligands attached to their outer Surfaces; exchanging the first ligands for second ligands of different chemical composition than the first ligands; forming a film of the ligand-exchanged nanocrystals; removing the second ligands; and fusing the cores of adjacent nanocrystals in the film to form an electrical network of fused nanocrystals. Under another aspect, a film includes a network of fused nanocrystals, the nanocrystals having a core and an outer surface, wherein the core of at least a portion of the fused nanocrystals is in direct physical contact and electrical communication with the core of at least one adjacent fused nanocrystal, and wherein the film has substantially no defect states in the regions where the cores of the nanocrystals are fused.

[0011] CN102280590B relates to an optical method for preparing an anode and a solar cell based on colloidal quantum dots and graphene, belonging to a photoelectric conversion, technical field of new materials and energy. ITO as the first skeleton, in which each graphene and colloidal quantum dots of different sizes are sequentially formed layer by layer deposition of graphene {/} quantum dot multilayer optical film as an anode, then the organic polymer mixture is then deposited onto the anode by the optical film according to rejection, and finally fabricating a solar cell device to complete vacuum deposition electrode on the organic polymer film. Preparation of a solar cell structure of the present invention is simple and inexpensive; capable of absorbing most of the energy of incident sunlight, the anode having light added graphene film high carrier mobility greatly improves the photogenerated carriers to the electrode extraction and transport process, thereby increasing the photoelectric conversion efficiency of solar cells.

[0012] US8685781B2 illustrates a method of forming an optoelectronic device. The method includes providing a deposition surface and contacting the deposition surface with a ligand exchange chemical and contacting the deposition surface with a quantum dot (QD) colloid. This initial process is repeated over one or more cycles to form an initial QD film on the deposition surface. The method further includes subsequently contacting the QD film with a secondary treatment chemical and optionally contacting the surface with additional QDs to form an enhanced QD layer exhibiting multiple exciton generation (MEG) upon absorption of high energy photons by the QD active layer. Devices having an enhanced QD active layer as described above are also disclosed.

[0013] US20110139248A1 presents the solar cells, methods for manufacturing a quantum dot layer for a solar cell, and methods for manufacturing solar cells are disclosed. An example method for manufacturing a quantum dot layer for a solar cell includes providing an electron conductor layer, providing a quantum dot chemical bath deposition solution, controlling the temperature of the quantum dot chemical bath deposition solution to a temperature of about 30° C. or greater, and immersing the electron conductor layer in the quantum dot chemical bath deposition solution for about 1-10 hours. The quantum dot chemical bath deposition solution may include CdSe. An example method for manufacturing a solar cell may include providing an electron conductor layer, providing a quantum dot chemical bath deposition solution, controlling the temperature of the quantum dot chemical bath deposition solution to a temperature from about 10° C. to 70° C., or lower or greater, immersing the electron conductor layer in the quantum dot chemical bath deposition solution for about 0.5-10 hours to form a quantum dot layer on the electron conductor layer, providing a hole conductor layer, and coupling the hole conductor layer to the quantum dot layer. The quantum dot chemical bath deposition solution may include CdSe.

[0014] EP2216839A2 relates generally to solar cells. In an illustrative but non-limiting example, the disclosure relates to a solar cell that includes a quantum dot layer, an electron conductor layer, an optional bifunctional ligand layer that is disposed between the quantum dot layer and the electron conductor layer, and a hole conductor layer that is disposed in contact with the quantum dot layer. The bifunctional ligand layer may include moieties that are configured to bond, either covalently or ionically, to the electron conductor as well as to quantum dots within the quantum dot layer. The hole conductor layer may be polymeric and may have pendant groups that are chemically similar to the moieties within the bifunctional ligand layer.In another illustrative but non-limiting example, the disclosure relates to a solar cell that includes a quantum dot, an electron conductor and a bifunctional ligand that is disposed between the quantum dot and the electron conductor. The bifunctional ligand may be a sulfur-based amino acid. A hole conductor having a pendant group that is chemically similar to the sulfur-based amino acid may be in contact with the quantum dot. In another illustrative but non-limiting example, the disclosure relates to a solar cell that includes a quantum dot, an electron conductor and a hole conductor having a pendant group including a sulfur-based amino acid. A bifunctional ligand that is chemically similar to the sulfur-based amino acid may be disposed between the quantum dot and the electron conductor.
[0015] The above summary is not intended to describe each disclosed embodiment or every implementation of the disclosure. The Figures and Detailed Description which follow more particularly exemplify these embodiments.

OBJECTS OF THE INVENTION
[0016] An object of the invention is to fabricate low cost and efficient organic solar cells by using in-situ synthesized inorganic quantum dots in polymer matrix as an active layer.

[0017] Another object of the invention is to improve the electronic interaction of donor and acceptor materials, resulting significant enhancement in the OSCs device performance.

[0018] Yet another object of the present invention is to synthesize inorganic quantum dots in the polymer matrix by in-situ route.
[0019] Still another object of the present invention is to prepare such material to be used as an active layer for the fabrication of efficient hybrid organic solar cells.

SUMMARY OF THE INVENTION
[0020] The present invention discloses and claims An hybrid organic solar cell, said cell in series comprising of an Indium Tin Oxide (ITO) coated glass substrate used as an anode electrode for light incident; a hole transport layer (HTL) deposited by thermal evaporation, in-situ synthesized inorganic quantum dots in polymer matrix used as an active layer combination (electron donor material and electron acceptor material), and an Aluminium (Al) cathode wherein said cathode and anode is sandwiching said active layer consists of Polymer (P3HT) matrix with in-situ synthesized PbSe QDs (P3HT:PbSe) with electron acceptor [6,6]-phenyl C61-butyric acid methyl ester (PC61BM) in 1:0.8 w/w and Molybdenum Oxide (MoO3) as HTL.

[0021] In addition, the process of in-situ synthesis of PbSe quantum dots in P3HT polymer matrix has also been claimed, said synthesis comprising the steps of preparing a solution of Lead (Pb) acetate by dissolving Pb acetate in the Trichlorobenzene (TCB) solvent at 1600C; adding Pb solution in P3HT solution of polymer with TCB solvent; preparing another solution by Selenium (Se) in Trioctylphosphine (TOP) then heating said solution at ~2000C, mixing both the solutions solution at 2000C in order to obtain in-situ synthesized PbSe qdots in P3HT polymer matrix, and optimizing concentration of PbSe/P3HT aalong with solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB) active layer material. The active layer material P3HT:PbSe/PC61BM were weighed (1:0.8 w/w) and dissolved in mixed solvents of CB and DCB, wherein further active layer solution was stirred for 12 hrs at room temperature. Thus the active layer consists of Polymer (P3HT) matrix with in-situ synthesized PbSe QDs (P3HT:PbSe) with electron acceptor [6,6]-phenyl C61-butyric acid methyl ester (PC61BM) in 1:0.8 w/w.

[0022] The method briefly comprising:
(a) For In-situ synthesis of PbSe quantum dots in P3HT polymer matrix.
(b) Make a solution of Lead (Pb) acetate, dissolve Pb acetate in the Trichlorobenzene (TCB) solvent and then heated at 1600C.
(c) After that added Pb solution in the solution of polymer P3HT with TCB solvent.
(d) Selenium (Se) added in Trioctylphosphine (TOP) then this solution heated at ~2000C.
(e) Added both Se and P3HT/Pb solution and heated at 2000C.
(f) Finally, we have confirmed the in-situ synthesized PbSe qdots in P3HT polymer matrix by different characterization techniques.
(g) After optimizing different concentrations of PbSe/P3HT material, we have selective concentration which gives better performance and used for the study.
(h) The optimized concentrations of PbSe/P3HT active material OSCs devices were fabricated.
(i) After OSCs fabrication J-V characteristics were measured.
(j) Also recorded the surface morphology images of HTL material.

[0023] Accordingly, the present invention provides using in-situ synthesized inorganic quantum dots inside the polymer matrix for fabrication of efficient hybrid solar cells.

BRIEF DESCRIPTION OF THE ACCOMPANYING FIGURES
Fig. 1: Schematic diagram of Organic Solar cell with MoO3 as a hole transport layer (HTL), wherein 1 is Substrate (glass), 2 is Anode (ITO coated glass), 3 is MoO3 used as HTL, 4 is Active Layer P3HT/ PbSe:PC61BM, and 5 is Al as Cathode.
Fig. 2: J-V Characteristics of P3HT:PC61BM based reference devices
Fig. 3: J-V Characteristics of P3HT: PbSe: PC61BM based devices.
Fig. 4: HRTEM images of P3HT/ PbSe active layer material.
Fig. 5: Thermal Stability graphs of Pure P3HT and P3HT/ PbSe material.
Fig. 6: XRD graphs of P3HT/ PbSe active layer material.
Fig. 7: SEM Micrographs of P3HT/ PbSe material.

DETAILED DESCRIPTION OF THE INVENTION
[0024] At the very outset of the detailed description, it may be understood that the ensuing description only illustrates a particular form of this invention. However, such a particular form is only exemplary embodiment, and without intending to imply any limitation on the scope of this invention. Accordingly, the description is to be understood as an exemplary embodiment and teaching of invention and not intended to be taken restrictively.

[0025] Throughout the description and claims of this specification, the phrases “comprise” and “contain” and variations of them mean “including but not limited to”, and are not intended to exclude other moieties, additives, components, integers or steps. Thus, the singular encompasses the plural unless the context otherwise requires. Wherever there is an indefinite article used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0026] Features, integers, characteristics, compounds, chemical moieties or groups described in conjunction with a particular aspect, embodiment or example of the invention are to be understood to be applicable to any other aspect, embodiment or example described herein unless incompatible therewith. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification including any accompanying claims, abstract and drawings or any parts thereof, or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

[0027] The reader's attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference. Post filing patents, original peer reviewed research paper shall be published.
[0028] The present invention describes the in-situ synthesis of Inorganic quantum dots for hybrid organic solar cells (OSCs). More specifically, inorganic quantum dots were synthesized by in-situ method in the polymer matrix for hybrid OSCs devices. The aim of the invention is to fabricate low cost and efficient organic solar cells by using in-situ synthesized inorganic quantum dots in polymer matrix as an active layer material, which improves the electronic interaction of donor and acceptor materials, resulting significant enhancement in the OSCs device performance. This invention describes an organic solar cell, which consist of an Indium Tin Oxide (ITO) coated glass substrate as anode electrode for light incident, a hole transport layer (HTL), an active layer combination of electron donor material and electron acceptor material duo. The active layer consist of Polymer: Inorganic QDs (P3HT: PbSe) and electron acceptor [6,6]-phenyl C61-butyric acid methyl ester (PC61BM), and an aluminium (Al) cathode electrode deposited by thermal evaporation, wherein said cathode and anode is sandwiching said active layer and HTL.

[0029] The present invention further describes a process of preparation of an organic solar cell comprising of an ITO coated glass substrate wherein the ITO coated glass substrate was patterned with the help of laser ablation system, cleaned with soap solution followed by cleaning with deionised water and boiled in different solvents such as acetone, methanol and isoprpanol, MoO3 as HTL, as the optimal concentration of active layer comprising of Polymer: Inorganic QDs (P3HT:PbSe)/ PC61BM, which are weighed and dissolved in mixed solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB), wherein further active layer solution was stirred for 12 hrs at room temperature, and Aluminium (Al) cathode.

Embodiments:
[0030] In one embodiment of the invention, the Inorganic QDs and Organic material (Polymer: QDs) chosen for study is P3HT:PbSe.

[0031] In another embodiment of the invention, the material taken as active layer was in-situ synthesized in the polymer matrix.

[0032] In another embodiment of the invention, the process synthesis of Polymer: QDs for hybrid organic solar fabrication is easy.

[0033] In another embodiment of the invention, the synthesized active layer material used is easily soluble in CB and DCB which is used in device fabrication.

[0034] In further embodiment of the invention, the quantity synthesized active layer material required ranges from 15mg/ml to 20 mg/ml.

[0035] In another embodiment of the invention, the HTL material thermally deposited on clean patterned ITO coated glass substrates.

[0036] In another embodiment of the invention, the solvents for active layer combination P3HT:PbSe/PC61BM was chlorobenzene and dichlorobenzene.

[0037] In one embodiment of the invention, after HTL active layer combination was spin coated on it with spin speed 1000 rpm.

[0038] In another embodiment of the invention, the active layer film was annealed at 1200C.

[0039] In another embodiment of the invention, after annealing cathode electrode (Al) were deposited by thermal evaporation method with base pressure 10-6 torr.
[0040] In another embodiment of the invention, J-V characteristics of the fabricated devices were characterized by using Keithley source meter having with power intensity 100mW/cm2.

[0041] In another embodiment of the invention, the in-situ synthesized active layer material (P3HT:PbSe) samples were tested by HRTEM,SEM,XRD and TGA.

[0042] The Table 1 discloses the operating parameters of OSCs based on the P3HT:PbSe/PC61BM and comparison with different operating parameters of OSCs based on the P3HT/PC61BM.

[0043] The following examples are given to illustrate the process of the present invention and should not be construed to limit the scope of the present invention:

Example 1:
Synthesis of Inorganic QDs in the polymer matrix by in situ process
[0044] In-situ synthesis of PbSe inorganic quantum dots in polymer matrix (P3HT) has been performed through preparing a solution of Lead (Pb) acetate, dissolving Pb acetate in the Trichlorobenzene (TCB) solvent and then heating at 1600C. After that Pb solution added in P3HT solution in TCB solvent. Another solution was prepared by Selenium (Se) in Trioctylphosphine (TOP) then heated it at ~2000C. Mixing of both the solutions such as Se and P3HT/ Pb solution and heated at 2000C. Finally, the in-situ synthesized PbSe qdots in P3HT polymer matrix by different characterization techniques has been confirmed.

Example 2:
Reference photovoltaic devices using Pure P3HT:PC61BM as an active layer material
[0045] A well known and widely used solution processed active layer material poly (3-hexylthiophene): [6,6]-phenyl C61-butyric acid methyl ester (PC61BM), is used in the fabrication of reference device. These devices were fabricated under same environmental conditions which are used in making devices using P3HT:PbSe/PC61BM active layer. These reference devices were fabricated for comparing the results with the in-situ synthesized hybrid active layer which is used in fabricating devices.

Example 3:
Device fabrication
[0046] The reference devices were fabricated with simple device geometry ITO/MoO3/active layer (P3HT:PC61BM)/Al. Prior to use, ITO coated glass (used as anode electrode) substrates are patterned with the help of laser ablation system after that cleaned with soap solution followed by deionized water. After that these substrates are boiled in different solvents like acetone, trichloroethylene and isopropanol respectively. For drying the substrates, said substrates are put inside the heating oven. After drying, a thin film of MoO3 layer is deposited by thermal evaporation. The well known active layer combination (P3HT:PC61BM) are weighed (1:0.8 w/w) and dissolved in mixed solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB). The active layer solution was stirred for 12 hrs at room temperature. After annealing the active layer solution were spin coated at 1000 rpm for 90 seconds and the resulting substrates are further annealed at 1200C. Finally devices were completed by the deposition of Al as a cathode electrode at a base pressure 10-6 torr.

Example 4:
Device characterization
[0047] All device measurements are performed in ambient conditions. The current-voltage (J-V) characteristics are measured using computer controlled keithley 2400 source meter. The devices are illuminated from the transparent ITO anode electrode side using a solar simulator with AM 1.5G and incident power is 100 mW/cm2. From J-V measurements, it has been found that the resulting reference devices show PCE with P3HT:PC61BM combination PCE is 1.29 %, Voc 0.49 V, Jsc 5.52 mA/cm2 and FF 45.4%, respectively (shown in figure 2 and Table 1).

Example 5:
Solution preparation of Hybrid (Organic/Inorganic) active Layer (P3HT:PbSe/ PC61BM) material

[0048] For this study, in-situ synthesized P3HT:PbSe was used as a solution processable active layer material. Different organic materials such as conducting polymers (P3HT, PCDTBT, PTB7 etc) are used as active layer materials. But these materials have their specific range of absorption so for increasing the absorption range of organic polymers or for better utilization of solar spectrum different inorganic nanoparticles, quantum dots and other material are used. Due to these reasons, PbSe is selected as inorganic material which synthesized by in situ process in polymer matriax as a solution processable active layer for efficient hybrid organic solar cells. First, P3HT:PbSe/PC61BM is weighed (1:4 w/w), then dissolved in a mixed solvent of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB). The active layer solution was stirred for 12 hrs at room temperature.

Example 6:
Process of device fabrication
[0049] All devices are fabricated on ITO coated glass substrates. ITO coated substrates are patterned using laser ablation technique. The patterned ITO coated substrates are cleaned in sequential with acetone, methanol and isopropanol, followed by drying for 20 min. After that the MoO3 HTL layer is thermally deposited on cleaned ITO substrates. The active layer solution (P3HT:PbSe/PC61BM) is spin-coated onto the HTL layer with spin speed of 1000 rpm and annealed at 120°C on a hot plate. Finally, the devices are completed by thermally deposited Al as cathode electrode at base pressure of 10-6 Torr. The completed devices are then transferred for the characterization.
Example 7:
In situ synthesized active layer material and device characterization

[0050] The surface morphology of in-situ synthesized active layer material (P3HT:PbSe) film on ITO substrates is acquired by using scanning microscopy (SEM). TGA spectra material is recorded for thermal stability of synthesized material. XRD, HRTEM characterization are also performed of synthesized material. To examine the effectiveness of in situ synthesized active layer material (P3HT:PbSe) for hybrid OSCs, fabrication of devices were performed by using simplest device structure ITO/HTL/active layer/Al. A most studied donor polymer P3HT with PbSe QDs blended with PC61BM is used as active layer for device fabrication. The current density–voltage (J–V) characteristics of fabricated devices are measured using a computer controlled Keithley 2400 source meter under dark and illumination conditions. The devices are illuminated from the transparent ITO anode electrode side using a solar simulator with AM 1.5G and incident power is 100 mW/cm2. From J-V characteristics, the device parameters are calculated and summarized in table 1 and the power conversion efficiency of fabricated devices with P3HT:PbSe/ PC61BM combination the device efficiencies are 2.10% and 1.70 % (shown in figure 3 and table 1).

Table 1: Comparison of different operating parameters of OSCs based on the P3HT:PbSe/PC61BM and P3HT/PC61BM active layer combination.
Active Layer Jsc (mA/cm2) Voc (V) FF (%) PCE (%)
P3HT/PC61BM 5.52 0.49 45.4 1.29
4.39 0.47 44.6 1.06
P3HT:PbSe/PC61BM 8.40 0.51 42.7 2.10
9.44 0.48 40.1 1.70

Claims:We Claim:
1. An hybrid organic solar cell, said cell in series comprising of:
a) an Indium Tin Oxide (ITO) coated glass substrate used as an anode electrode for light incident;
b) a hole transport layer (HTL) deposited by thermal evaporation,
c) in-situ synthesized inorganic quantum dots in polymer matrix used as an active layer combination (electron donor material and electron acceptor material), and
d) a cathode wherein said cathode and anode is sandwiching said active layers and HTL.
2. The hybrid organic cell as claimed in claim 1, wherein said HTL is Molybdenum Oxide (MoO3).
3. The hybrid organic cell as claimed in claim 1, wherein said active layer consists of Polymer (P3HT) matrix with in-situ synthesized PbSe QDs (P3HT:PbSe) with electron acceptor [6,6]-phenyl C61-butyric acid methyl ester (PC61BM) in 1:0.8 w/w.
4. The hybrid organic cell as claimed in claim 1, wherein said cathode is Aluminium (Al).
5. The process as claimed in claim 1, wherein ITO coated glass substrate is patterned with the help of laser ablation system, cleaned with soap solution followed by cleaning with deionised water after that boiled in around 100 ml of acetone, methanol and isopropanol respectively.
6. In-situ synthesis of PbSe quantum dots in P3HT polymer matrix, said synthesis comprising the steps of:
a) Preparing a solution of Lead (Pb) acetate by dissolving Pb acetate in the Trichlorobenzene (TCB) solvent at 1600C;
b) Adding Pb solution in P3HT solution of polymer with TCB solvent;
c) Preparing another solution by Selenium (Se) in Trioctylphosphine (TOP) then heating said solution at ~2000C,
d) Mixing both the solutions solution at 2000C in order to obtain in-situ synthesized PbSe qdots in P3HT polymer matrix, and
f) Optimizing concentration of PbSe/P3HT aalong with solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB) active layer material.
7. The process as claimed in claim 6, wherein said active layer material P3HT:PbSe/PC61BM were weighed (1:0.8 w/w) and dissolved in mixed solvents of CB and DCB, wherein further active layer solution was stirred for 12 hrs at room temperature.
8. The hybrid organic cell as claimed in claim 7, wherein said active layer consists of Polymer (P3HT) matrix with in-situ synthesized PbSe QDs (P3HT:PbSe) with electron acceptor [6,6]-phenyl C61-butyric acid methyl ester (PC61BM) in 1:0.8 w/w.