ZnS and Graphene Quantum Dots Nanocomposite as Potential Electron Acceptor for Photovoltaics
Zinc sulphide (ZnS) quantum dots (QDs) were synthesized successfully via simple sonochemical method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) analysis revealed the average size of QDs of the order of 3.7 nm. The band gap of the QDs was tuned to 5.2 eV by optimizing the synthesis parameters. UV-Vis absorption spectra of ZnS QD confirm the quantum confinement effect. Fourier transform infrared (FTIR) analysis confirmed the formation of single phase ZnS QDs. To fabricate the diode, blend of ZnS QDs and P3HT was prepared and the heterojunction of PEDOT:PSS and the blend was formed by spin coating on indium tin oxide (ITO) coated glass substrate. The diode behaviour of the heterojunction was analysed, wherein the ideality factor was found to be 2.53 with turn on voltage 0.75 V and the barrier height was found to be 1.429 eV. ZnS-Graphene QDs nanocomposite was characterised for the surface morphological study. It was found that the synthesized ZnS QDs appear as quasi spherical particles on the graphene sheets. The average particle size of ZnS-graphene nanocomposite QDs was found to be 8.4 nm. From voltage-current characteristics of ZnS-graphene nanocomposites, it is observed that the conductivity of the composite increases by 104 times the conductivity of ZnS QDs. Thus the addition of graphene QDs in ZnS QDs enhances the mobility of the charge carriers in the composite material. Thus, the graphene QDs, with high specific area for a large interface, high mobility and tunable band gap, show a great potential as an electron-acceptors in photovoltaic devices.
[1] P. Peumans, S. Uchida, S.R. Forrest, Efficient bulk heterojunction photovoltaic cells using small-molecular-weight organic thin films, Nature 425 (2003) 158-162.
[2] R. Liu, Hybrid Organic/Inorganic Nanocomposites for Photovoltaic Cells, Materials 7 (2014) 2747-2771.s
[3] T. Lin, F. Huang, J. Liang, Y. Wang, A facile preparation route for boron-doped graphene, and its CdTe solar cell application, Energy & Environmental Science 4 (2011) 862-865.
[4] Y. Zhou, M. Eck, C. Men, F. Rauscher, P. Niyamakom, S. Yilmaz, I. Dumsch, S. Allard, U. Scherf, M. Kruger, Efficient polymer nanocrystal hybrid solar cells by improved nanocrystal composition, Solar Energy Materials & Solar Cells 95 (2011) 3227-3232.
[5] Z. Pan, H. Zhang, K. Cheng, Y. Hou, J. Hua, X. Zhong, Highly Efficient Inverted Type-I CdS/CdSe Core/Shell Structure QD-Sensitized Solar Cells, ACS Nano 6 (2012) 3982-3991.
[6] C. Gretener, J. Perrenoud, L. Kranz, L. Kneer, R. Schmitt, S. Buecheler, A.N. Tiwari, CdTe/CdS thin film solar cells grown in substrate configuration, Prog. Photovolt:Res. Appl. (2012) doi:10.1002/pip.2233.
[7] L.Y. Chang, R.R. Lunt, P.R. Brown, V. Bulovic, M.G. Bawendi, Low-Temperature Solution-Processed Solar Cells Based on PbS Colloidal Quantum Dot/CdS Heterojunctions, Nano Letters 13 (2013) 994-999.
[8] J.N. Freitas, A.S. Goncalves, A.F. Nogueira, A comprehensive review of the application of chalcogenide nanoparticles in polymer solar cells, Nanoscale 6 (2014) 6371-6397.
[9] L.H. Lai, L. Protesescu, M.V. Kovalenko, M.A. Loi, Sensitized solar cells with colloidal PbS–CdS core–shell quantum dots, Phys. Chem. Chem. Phys 16 (2014) 736-742.
[10] R. Ahmed, L. Zhao, A.J. Mozer, G. Will, J. Bell, H. Wang, Enhanced Electron Lifetime of CdSe/CdS Quantum Dot (QD) Sensitized Solar Cells Using ZnSe Core−Shell Structure with Efficient Regeneration of Quantum Dots, J. Phys. Chem. C 119 (2015) 2297-2307.
[11] M.E. Mathew, J.C. Mohan, K. Manzoor, S.V. Nair H. Tamura, R. Jayakumar, Folate conjugated carboxymethyl chitosan–manganese doped zinc sulphide nanoparticles for targeted drug delivery and imaging of cancer cells, Carbohydrate Polymers 80 (2010) 442–448.
[12] F.Y. Shen, W. Que, X.T. Yin, Y.W. Huang, Q.Y. Jia, A facile method to synthesize high quality ZnS(Se) quantum dots for photoluminescence, Journal of Alloys and Compounds 509 (2011) 9105-9110.
[13] X. Wang, H. Hu, S. Chen, K. Zhang, J. Zhang, W. Zou, R. Wang, One-step fabrication of BiOCl/CuS heterojunction photocatalysts with enhanced visible-light responsive activity, Materials Chemistry and Physics (2015) 1-7.
[14] N.S.N. Jothi, A.G. Joshi, R.J. Vijay, A. Muthuvinayagam, P. Sagayaraj, Investigation on one-pot hydrothermal synthesis, structural and optical properties of ZnS quantum dots, Materials Chemistry and Physics 138 (2013) 186-191.
[15] S. Chaguetmi, F. Mammeri, S. Nowak, P. Decorse, H. Lecoq, M. Gaceur, J.B. Naceur, S. Achour, R. Chtourou, S. Ammar, Photocatalytic activity of TiO2 nanofibers sensitized with ZnS quantum dots, RSC Advances 3 (2013) 2572-2580.
[16] T. Zhao, X. Hou, Y.N. Xie, L. Wu, P. Wu, Phosphorescent sensing of Cr3+ with proteinfunctionalized Mn-doped ZnS quantum dots, Analyst 138 (2013) 6589-6594.
[17] D.I. Son, H.H. Kim, D.K. Hwang, S. Kwon, W.K. Choi, Inverted CdSe–ZnS quantum dots light-emitting diode using low-work function organic material polyethylenimine ethoxylated, J. Mater. Chem. C 2 (2014) 510-514.
[18] C. Ippen, T. Greco, Y. Kim, J. Kim, M.S. Oh, C.J. Han, A. Wedel, ZnSe/ZnS quantum dots as emitting material in blue QD-LEDs with narrow emission peak and wavelength tenability, Organic Electronics 15 (2014) 126-131.
[19] M. Mehrabian, K. Mirabbaszadeh, H. Afarideh, Solid-state ZnS quantum dot-sensitized solar cell fabricated by the Dip-SILAR technique, Phys. Scr 89 (2014) 1-8.
[20] H.S. Mansur, A.A.P Mansur, A. Soriano-Araújo, Z.I.P. Lobato, Beyond Biocompatibility: A Novel Approach for the Synthesis of ZnS Quantum Dot-Chitosan Nano-Immunoconjugates for Cancer Diagnosis, Green Chemistry (2015) doi:10.1039/C4GC02072C.
[21] M.R. Kumar, N. Ramamurthy, P. Ambalavanan, Synthesis, structure and optical characterization of zns nanoparticles, International Journal of Current Physical Sciences 1 (2011) 6-9.
[22] J. Kim, C. Park, S.M. Pawar, A.I. Inamdar, Y. Jo, J.Han, J.P. Hong, Y.S. Parkc, D.-Y. Kim, W. Jung, H. Kim, H. Im, Optimization of sputtered ZnS buffer for Cu2ZnSnS4 thin film solar cells, Thin Solid Films 566 (2014) 88–92.
[23] H. Chang and Hongkai Wu, Graphene-based nanocomposites: preparation, functionalization, and energy and environmental applications, Energy Environ. Sci., 6 (2013) 3483–3507.
[24] Y. Yu, Y. Yang, H. Gu, D. Yub, G. Shi, Size-controllable preparation of palladium nanoparticles assembled on TiO2/graphene nanosheets and their electrocatalytic activity for glucose biosensing, Anal. Methods 5 (2013) 7049-7057.
[25] C. Hu , T. Lu , F. Chen, R. Zhang, A brief review of graphene–metal oxide composites synthesis and applications in photocatalysis, Journal of the Chinese Advanced Materials Society 1 (1) (2013) 21-39.
[26] Y. Lei, R. Li, F. Chen, J. Xu, Hydrothermal synthesis of graphene–CdS composites with improved photoelectric characteristics, J Mater Sci: Mater Electron 25 (2014) 3057-3061.
[27] L. Jiang, M. Yao, B. Liu, Q. Li, R. Liu, H. Lv, S. Lu, C. Gong, B. Zou, T. Cui, B. Liu, Controlled Synthesis of CeO2/Graphene Nanocomposites with Highly Enhanced Optical and Catalytic Properties, J. Phys. Chem. C 116 (2012) 11741-11745.
[28] X. Li, X. Wang, L. Zhang, S. Lee, H. Dai, Chemically Derived, Ultrasmooth Graphene Nanoribbon SemiconductorsScience 319 (2008) 1229-1232.
[29] S.K. Kim, D. Yoon, S.-C. Lee, J. Kim, Mo2C/Graphene Nanocomposite As a Hydrodeoxygenation Catalyst for the Production of Diesel Range Hydrocarbons, ACS Catalysis 5 (6) (2015) 3292–3303,doi:10.1021/acscatal.5b00335.
[30] D. Chen, W. Chen, L. Ma, G. Ji, K. Chang, J.Y. Lee, Graphene-like layered metal dichalcogenide/graphene composites: synthesis and applications in energy storage and conversion, Materials Today 17 (4) (2014) 184-193.
[31] Jaidev, S. Ramaprabhu, Poly(p-phenylenediamine)/graphene nanocomposites for supercapacitor applications, J. Mater. Chem. 22 (2012) 18775–18783.
[32] M. Sookhakian, Y. M. Amin, S. Baradaran , M. T. Tajabadi, A. M. Golsheikh, W. J. Basirun, A layer-by-layer assembled graphene/zinc sulfide/polypyrrole thin-film electrode via electrophoretic deposition for solar cells, Thin Solid Films 552 (2014) 204–211.
[33] L. Scudiero, Y. Shen, M.C. Gupta, Effect of light illumination and temperature on P3HT films, n-type Si,and ITO, Applied Surface Science 292 (2014) 100-106.
[34] P. Ramidi, O. Abdulrazzaq, C.M. Felton, Y. Gartia, V. Saini, A.S. Biris, A. Ghosh, Triplet Sensitizer Modification of Poly(3-hexyl)thiophene (P3HT) for Increased Efficiency in Bulk Heterojunction Photovoltaic Devices, Energy Technol.2 (2014) 604-611.
[35] M.J.M. Wirix, P.H.H. Bomans, H. Friedrich, N.A.J.M. Sommerdijk, G.de With, Three-Dimensional Structure of P3HT Assemblies in Organic Solvents Revealed by Cryo-TEM, Nano Lett. 14 (2014) 2033−2038.
[36] W.-F. Fu, Y. Shi, L. Wang, M.-M. Shi, H.-Y. Li, H.-Z. Chen, A green, low-cost, and highly effective strategy to enhance the performance of hybrid solar cells: Post-deposition ligand exchange by acetic acid, Solar Energy Materials & Solar Cells 117 (2013) 329-335.
[37] S.-H. Choi, H. Song, I.K. Park, J.-H. Yum, S.-S. Kim, S. Lee, Y.-E. Sung, Synthesis of size-controlled CdSe quantum dots and characterization of CdSe–conjugated polymer blends for hybrid solar cells, Journal of Photochemistry and Photobiology A: Chemistry 179 (2006) 135-141.
[38] C.Y. Kwong, W.C.H. Choy, A.B. Djurisic, P.C. Chui, K.W. Cheng, W.K. Chan, Poly(3-hexylthiophene):TiO2 nanocomposites for solar cell applications, Nanotechnology 15 (2004) 1156-1161.
[39] J. Wu, G. Yue, Y. Xiao, J. Lin, M. Huang, Z. Lan, Q. Tang, Y. Huang, L. Fan, S. Yin, T. Sato, An ultraviolet responsive hybrid solar cell based on titania/poly(3-hexylthiophene), Scientific Reports 3:1283 (2013)1-6.
[40] Y. Firdaus, E. Vandenplas, Y. Justo, R. Gehlhaar, D. Cheyns, Z. Hens, M. V. Auweraer, Enhancement of the photovoltaic performance in P3HT: PbS hybrid solar cells using small size PbS quantum dots, Journal of Applied Physics, 116 (2014) 094305.
[41] S.A. Mauger, L. Chang, C.W. Rochester, A.J. Moule, Directional dependence of electron blocking in PEDOT:PSS, Organic Electronics 13 (2012) 2747–2756.
[42] S.B. Dkhil, R. Ebdelli, W. Dachraoui, H. Faltakh, R. Bourguiga, J. Davenas, Improved photovoltaic performance of hybrid solar cells based on silicon nanowire and P3HT, Synthetic Metals 192 (2014) 74-81.
[43] S.D. Oosterhout, M.M. Wienk, S.S. van Bavel, R. Thiedmann, L.J.A. Koster, J. Gilot, J. Loos, V. Schmidt, R.A.J. Janssen, The effect of three-dimensional morphology on the efficiency of hybrid polymer solar cells, Nature Materials 8 (2009) 818-824.
[44] E.K. Goharshadi, S.H. Sajjadi, R. Mehrkhah, P. Nancarrow, Sonochemical synthesis and measurement of optical properties of zinc sulfide quantum dots, Chemical Engineering Journal 209 (2012) 113-117.
[45] Z. Tang, H. Wu, J. R. Cort, G. W. Buchko, Y. Zhang, Y. Shao, I. A. Aksay, J. Liu, Y. Lin, Constraint of DNA on Functionalized Graphene Improves its Biostability and Specificity, Small, 6(11) (2010) 1205–1209.
[46] S.-D. Jiang, G. Tang, Y.-F. Ma, Y. Hu, L. Song, Synthesis of nitrogen-doped graphene-ZnS quantum dots composites with highly efficient visible light photodegradation, Materials Chemistry and Physics (2014) 1-9.
[47] Z. Jindal, N.K. Verma, Photoluminescent properties of ZnS:Mn nanoparticles with in-built surfactant, J. Mater. Sci. 43 (2008) 6539-6545.
[48] M.R. Karim, Synthesis and Characterizations of Poly(3-hexylthiophene) and Modified Carbon Nanotube Composites, Journal of Nanomaterials (2012) doi:10.1155/2012/174353.
[49] G.A.H. Wetzelaer, P.W.M Blom, Diffusion-driven currents in organic-semiconductor diodes, NPG Asia Materials (2014) doi:10.1038/am.2014.41.
[50] O. Breitenstein, P. Altermatt, K. Ramspeck, M.A. Green, Jianhua Zhao, A. Schenk, Interpretation of the Commonly Observed I-V Characteristics of C-Si Cells Having Ideality factor Larger Than Two IEEE Xplore (2006) doi: 10.1109/WCPEC.2006.279597.
[1] P. Peumans, S. Uchida, S.R. Forrest, Efficient bulk heterojunction photovoltaic cells using small-molecular-weight organic thin films, Nature 425 (2003) 158-162.
[2] R. Liu, Hybrid Organic/Inorganic Nanocomposites for Photovoltaic Cells, Materials 7 (2014) 2747-2771.s
[3] T. Lin, F. Huang, J. Liang, Y. Wang, A facile preparation route for boron-doped graphene, and its CdTe solar cell application, Energy & Environmental Science 4 (2011) 862-865.
[4] Y. Zhou, M. Eck, C. Men, F. Rauscher, P. Niyamakom, S. Yilmaz, I. Dumsch, S. Allard, U. Scherf, M. Kruger, Efficient polymer nanocrystal hybrid solar cells by improved nanocrystal composition, Solar Energy Materials & Solar Cells 95 (2011) 3227-3232.
[5] Z. Pan, H. Zhang, K. Cheng, Y. Hou, J. Hua, X. Zhong, Highly Efficient Inverted Type-I CdS/CdSe Core/Shell Structure QD-Sensitized Solar Cells, ACS Nano 6 (2012) 3982-3991.
[6] C. Gretener, J. Perrenoud, L. Kranz, L. Kneer, R. Schmitt, S. Buecheler, A.N. Tiwari, CdTe/CdS thin film solar cells grown in substrate configuration, Prog. Photovolt:Res. Appl. (2012) doi:10.1002/pip.2233.
[7] L.Y. Chang, R.R. Lunt, P.R. Brown, V. Bulovic, M.G. Bawendi, Low-Temperature Solution-Processed Solar Cells Based on PbS Colloidal Quantum Dot/CdS Heterojunctions, Nano Letters 13 (2013) 994-999.
[8] J.N. Freitas, A.S. Goncalves, A.F. Nogueira, A comprehensive review of the application of chalcogenide nanoparticles in polymer solar cells, Nanoscale 6 (2014) 6371-6397.
[9] L.H. Lai, L. Protesescu, M.V. Kovalenko, M.A. Loi, Sensitized solar cells with colloidal PbS–CdS core–shell quantum dots, Phys. Chem. Chem. Phys 16 (2014) 736-742.
[10] R. Ahmed, L. Zhao, A.J. Mozer, G. Will, J. Bell, H. Wang, Enhanced Electron Lifetime of CdSe/CdS Quantum Dot (QD) Sensitized Solar Cells Using ZnSe Core−Shell Structure with Efficient Regeneration of Quantum Dots, J. Phys. Chem. C 119 (2015) 2297-2307.
[11] M.E. Mathew, J.C. Mohan, K. Manzoor, S.V. Nair H. Tamura, R. Jayakumar, Folate conjugated carboxymethyl chitosan–manganese doped zinc sulphide nanoparticles for targeted drug delivery and imaging of cancer cells, Carbohydrate Polymers 80 (2010) 442–448.
[12] F.Y. Shen, W. Que, X.T. Yin, Y.W. Huang, Q.Y. Jia, A facile method to synthesize high quality ZnS(Se) quantum dots for photoluminescence, Journal of Alloys and Compounds 509 (2011) 9105-9110.
[13] X. Wang, H. Hu, S. Chen, K. Zhang, J. Zhang, W. Zou, R. Wang, One-step fabrication of BiOCl/CuS heterojunction photocatalysts with enhanced visible-light responsive activity, Materials Chemistry and Physics (2015) 1-7.
[14] N.S.N. Jothi, A.G. Joshi, R.J. Vijay, A. Muthuvinayagam, P. Sagayaraj, Investigation on one-pot hydrothermal synthesis, structural and optical properties of ZnS quantum dots, Materials Chemistry and Physics 138 (2013) 186-191.
[15] S. Chaguetmi, F. Mammeri, S. Nowak, P. Decorse, H. Lecoq, M. Gaceur, J.B. Naceur, S. Achour, R. Chtourou, S. Ammar, Photocatalytic activity of TiO2 nanofibers sensitized with ZnS quantum dots, RSC Advances 3 (2013) 2572-2580.
[16] T. Zhao, X. Hou, Y.N. Xie, L. Wu, P. Wu, Phosphorescent sensing of Cr3+ with proteinfunctionalized Mn-doped ZnS quantum dots, Analyst 138 (2013) 6589-6594.
[17] D.I. Son, H.H. Kim, D.K. Hwang, S. Kwon, W.K. Choi, Inverted CdSe–ZnS quantum dots light-emitting diode using low-work function organic material polyethylenimine ethoxylated, J. Mater. Chem. C 2 (2014) 510-514.
[18] C. Ippen, T. Greco, Y. Kim, J. Kim, M.S. Oh, C.J. Han, A. Wedel, ZnSe/ZnS quantum dots as emitting material in blue QD-LEDs with narrow emission peak and wavelength tenability, Organic Electronics 15 (2014) 126-131.
[19] M. Mehrabian, K. Mirabbaszadeh, H. Afarideh, Solid-state ZnS quantum dot-sensitized solar cell fabricated by the Dip-SILAR technique, Phys. Scr 89 (2014) 1-8.
[20] H.S. Mansur, A.A.P Mansur, A. Soriano-Araújo, Z.I.P. Lobato, Beyond Biocompatibility: A Novel Approach for the Synthesis of ZnS Quantum Dot-Chitosan Nano-Immunoconjugates for Cancer Diagnosis, Green Chemistry (2015) doi:10.1039/C4GC02072C.
[21] M.R. Kumar, N. Ramamurthy, P. Ambalavanan, Synthesis, structure and optical characterization of zns nanoparticles, International Journal of Current Physical Sciences 1 (2011) 6-9.
[22] J. Kim, C. Park, S.M. Pawar, A.I. Inamdar, Y. Jo, J.Han, J.P. Hong, Y.S. Parkc, D.-Y. Kim, W. Jung, H. Kim, H. Im, Optimization of sputtered ZnS buffer for Cu2ZnSnS4 thin film solar cells, Thin Solid Films 566 (2014) 88–92.
[23] H. Chang and Hongkai Wu, Graphene-based nanocomposites: preparation, functionalization, and energy and environmental applications, Energy Environ. Sci., 6 (2013) 3483–3507.
[24] Y. Yu, Y. Yang, H. Gu, D. Yub, G. Shi, Size-controllable preparation of palladium nanoparticles assembled on TiO2/graphene nanosheets and their electrocatalytic activity for glucose biosensing, Anal. Methods 5 (2013) 7049-7057.
[25] C. Hu , T. Lu , F. Chen, R. Zhang, A brief review of graphene–metal oxide composites synthesis and applications in photocatalysis, Journal of the Chinese Advanced Materials Society 1 (1) (2013) 21-39.
[26] Y. Lei, R. Li, F. Chen, J. Xu, Hydrothermal synthesis of graphene–CdS composites with improved photoelectric characteristics, J Mater Sci: Mater Electron 25 (2014) 3057-3061.
[27] L. Jiang, M. Yao, B. Liu, Q. Li, R. Liu, H. Lv, S. Lu, C. Gong, B. Zou, T. Cui, B. Liu, Controlled Synthesis of CeO2/Graphene Nanocomposites with Highly Enhanced Optical and Catalytic Properties, J. Phys. Chem. C 116 (2012) 11741-11745.
[28] X. Li, X. Wang, L. Zhang, S. Lee, H. Dai, Chemically Derived, Ultrasmooth Graphene Nanoribbon SemiconductorsScience 319 (2008) 1229-1232.
[29] S.K. Kim, D. Yoon, S.-C. Lee, J. Kim, Mo2C/Graphene Nanocomposite As a Hydrodeoxygenation Catalyst for the Production of Diesel Range Hydrocarbons, ACS Catalysis 5 (6) (2015) 3292–3303,doi:10.1021/acscatal.5b00335.
[30] D. Chen, W. Chen, L. Ma, G. Ji, K. Chang, J.Y. Lee, Graphene-like layered metal dichalcogenide/graphene composites: synthesis and applications in energy storage and conversion, Materials Today 17 (4) (2014) 184-193.
[31] Jaidev, S. Ramaprabhu, Poly(p-phenylenediamine)/graphene nanocomposites for supercapacitor applications, J. Mater. Chem. 22 (2012) 18775–18783.
[32] M. Sookhakian, Y. M. Amin, S. Baradaran , M. T. Tajabadi, A. M. Golsheikh, W. J. Basirun, A layer-by-layer assembled graphene/zinc sulfide/polypyrrole thin-film electrode via electrophoretic deposition for solar cells, Thin Solid Films 552 (2014) 204–211.
[33] L. Scudiero, Y. Shen, M.C. Gupta, Effect of light illumination and temperature on P3HT films, n-type Si,and ITO, Applied Surface Science 292 (2014) 100-106.
[34] P. Ramidi, O. Abdulrazzaq, C.M. Felton, Y. Gartia, V. Saini, A.S. Biris, A. Ghosh, Triplet Sensitizer Modification of Poly(3-hexyl)thiophene (P3HT) for Increased Efficiency in Bulk Heterojunction Photovoltaic Devices, Energy Technol.2 (2014) 604-611.
[35] M.J.M. Wirix, P.H.H. Bomans, H. Friedrich, N.A.J.M. Sommerdijk, G.de With, Three-Dimensional Structure of P3HT Assemblies in Organic Solvents Revealed by Cryo-TEM, Nano Lett. 14 (2014) 2033−2038.
[36] W.-F. Fu, Y. Shi, L. Wang, M.-M. Shi, H.-Y. Li, H.-Z. Chen, A green, low-cost, and highly effective strategy to enhance the performance of hybrid solar cells: Post-deposition ligand exchange by acetic acid, Solar Energy Materials & Solar Cells 117 (2013) 329-335.
[37] S.-H. Choi, H. Song, I.K. Park, J.-H. Yum, S.-S. Kim, S. Lee, Y.-E. Sung, Synthesis of size-controlled CdSe quantum dots and characterization of CdSe–conjugated polymer blends for hybrid solar cells, Journal of Photochemistry and Photobiology A: Chemistry 179 (2006) 135-141.
[38] C.Y. Kwong, W.C.H. Choy, A.B. Djurisic, P.C. Chui, K.W. Cheng, W.K. Chan, Poly(3-hexylthiophene):TiO2 nanocomposites for solar cell applications, Nanotechnology 15 (2004) 1156-1161.
[39] J. Wu, G. Yue, Y. Xiao, J. Lin, M. Huang, Z. Lan, Q. Tang, Y. Huang, L. Fan, S. Yin, T. Sato, An ultraviolet responsive hybrid solar cell based on titania/poly(3-hexylthiophene), Scientific Reports 3:1283 (2013)1-6.
[40] Y. Firdaus, E. Vandenplas, Y. Justo, R. Gehlhaar, D. Cheyns, Z. Hens, M. V. Auweraer, Enhancement of the photovoltaic performance in P3HT: PbS hybrid solar cells using small size PbS quantum dots, Journal of Applied Physics, 116 (2014) 094305.
[41] S.A. Mauger, L. Chang, C.W. Rochester, A.J. Moule, Directional dependence of electron blocking in PEDOT:PSS, Organic Electronics 13 (2012) 2747–2756.
[42] S.B. Dkhil, R. Ebdelli, W. Dachraoui, H. Faltakh, R. Bourguiga, J. Davenas, Improved photovoltaic performance of hybrid solar cells based on silicon nanowire and P3HT, Synthetic Metals 192 (2014) 74-81.
[43] S.D. Oosterhout, M.M. Wienk, S.S. van Bavel, R. Thiedmann, L.J.A. Koster, J. Gilot, J. Loos, V. Schmidt, R.A.J. Janssen, The effect of three-dimensional morphology on the efficiency of hybrid polymer solar cells, Nature Materials 8 (2009) 818-824.
[44] E.K. Goharshadi, S.H. Sajjadi, R. Mehrkhah, P. Nancarrow, Sonochemical synthesis and measurement of optical properties of zinc sulfide quantum dots, Chemical Engineering Journal 209 (2012) 113-117.
[45] Z. Tang, H. Wu, J. R. Cort, G. W. Buchko, Y. Zhang, Y. Shao, I. A. Aksay, J. Liu, Y. Lin, Constraint of DNA on Functionalized Graphene Improves its Biostability and Specificity, Small, 6(11) (2010) 1205–1209.
[46] S.-D. Jiang, G. Tang, Y.-F. Ma, Y. Hu, L. Song, Synthesis of nitrogen-doped graphene-ZnS quantum dots composites with highly efficient visible light photodegradation, Materials Chemistry and Physics (2014) 1-9.
[47] Z. Jindal, N.K. Verma, Photoluminescent properties of ZnS:Mn nanoparticles with in-built surfactant, J. Mater. Sci. 43 (2008) 6539-6545.
[48] M.R. Karim, Synthesis and Characterizations of Poly(3-hexylthiophene) and Modified Carbon Nanotube Composites, Journal of Nanomaterials (2012) doi:10.1155/2012/174353.
[49] G.A.H. Wetzelaer, P.W.M Blom, Diffusion-driven currents in organic-semiconductor diodes, NPG Asia Materials (2014) doi:10.1038/am.2014.41.
[50] O. Breitenstein, P. Altermatt, K. Ramspeck, M.A. Green, Jianhua Zhao, A. Schenk, Interpretation of the Commonly Observed I-V Characteristics of C-Si Cells Having Ideality factor Larger Than Two IEEE Xplore (2006) doi: 10.1109/WCPEC.2006.279597.
@article{"International Journal of Chemical, Materials and Biomolecular Sciences:76780", author = "S. M. Giripunje and Shikha Jindal", title = "ZnS and Graphene Quantum Dots Nanocomposite as Potential Electron Acceptor for Photovoltaics", abstract = "Zinc sulphide (ZnS) quantum dots (QDs) were synthesized successfully via simple sonochemical method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) analysis revealed the average size of QDs of the order of 3.7 nm. The band gap of the QDs was tuned to 5.2 eV by optimizing the synthesis parameters. UV-Vis absorption spectra of ZnS QD confirm the quantum confinement effect. Fourier transform infrared (FTIR) analysis confirmed the formation of single phase ZnS QDs. To fabricate the diode, blend of ZnS QDs and P3HT was prepared and the heterojunction of PEDOT:PSS and the blend was formed by spin coating on indium tin oxide (ITO) coated glass substrate. The diode behaviour of the heterojunction was analysed, wherein the ideality factor was found to be 2.53 with turn on voltage 0.75 V and the barrier height was found to be 1.429 eV. ZnS-Graphene QDs nanocomposite was characterised for the surface morphological study. It was found that the synthesized ZnS QDs appear as quasi spherical particles on the graphene sheets. The average particle size of ZnS-graphene nanocomposite QDs was found to be 8.4 nm. From voltage-current characteristics of ZnS-graphene nanocomposites, it is observed that the conductivity of the composite increases by 104 times the conductivity of ZnS QDs. Thus the addition of graphene QDs in ZnS QDs enhances the mobility of the charge carriers in the composite material. Thus, the graphene QDs, with high specific area for a large interface, high mobility and tunable band gap, show a great potential as an electron-acceptors in photovoltaic devices.
", keywords = "Graphene, mobility, nanocomposites, photovoltaics, quantum dots, zinc sulphide.", volume = "11", number = "12", pages = "840-6", }
