Efficiency and stability are the main challenges of organic solar cells. In this research novel structure is investigated for organic solar cell which has improved efficiency and improved stability. Blend of PTB7 and PCBM elements was used for the active layer of cell. Thickness of this layer was varied from 80nm to 200nm and selected the optimized thickness of 90nm. On which the cell has maximum efficiency of 12.24 %. The influence of window layer material such as Zinc oxide (ZnO) and titanium dioxide (TiO2) with various electrode materials including Indium tin oxide (ITO), Fluorine tin oxide (FTO), aluminum (Al) Silver (Ag) and Gold (Au) with different combinations have been investigated with the objective to enhance the absorption and PCE of the cell. Also varied the thicknesses of these different layers and selected the optimized thickness on which the cell had maximum efficiency. The structure of the proposed scheme was observed with ITO/Al as top and bottom electrode with thicknesses of 125nm and 100nm respectively and found that this holds the highest performance parameters including Jsc=0.130(mA/m2), Voc= 1 (V), FF=94.1% and ƞ=12.24% respectively as compared to different electrode combination and window layers with the same photoactive absorber material PTB7: PCBM. This indicates that the proposed structure can be a good choice for replacing less efficient in-organic cell.
Muhammad Zeeshan Improving Efficiency and Stability of Organic Solar Cell International Journal of Engineering Works Vol. 7 Issue 10 PP. 375-378 October 2020 https://doi.org/10.34259/ijew.20.710375378.
 Goetzberger, A., J. Luther, and G. Willeke, Solar cells: past, present, future. Solar energy materials and solar cells, 2002. 74(1-4): p. 1-11.
 Bagher, A.M., Comparison of organic solar cells and inorganic solar cells. International Journal of Renewable and Sustainable Energy, 2014. 3(3): p. 53-58.
 Goetzberger, A., J. Knobloch, and B. Voss, Crystalline silicon solar cells. New York, 1998: p. 114-118.
 Green, M.A., Corrigendum to ‘Solar cell efficiency tables (version 46)’[Prog. Photovolt: Res. Appl. 2015; 23: 805–812]. Progress in Photovoltaics: Research and Applications, 2015. 23(9): p. 1202-1202.
 Sahare, S.A., Enhancing the Photovoltaic Efficiency of a Bulk Heterojunction Organic Solar Cell. 2016.
 Winder, C., et al., Sensitization of low bandgap polymer bulk heterojunction solar cells. Thin Solid Films, 2002. 403: p. 373-379.
 Zhang, F., et al., High photovoltage achieved in low band gap polymer solar cells by adjusting energy levels of a polymer with the LUMOs of fullerene derivatives. Journal of Materials Chemistry, 2008. 18(45): p. 5468-5474.
 Tang, C.W., Two‐layer organic photovoltaic cell. Applied physics letters, 1986. 48(2): p. 183-185.
 松本真哉, et al., 真空蒸着膜におけるビスアゾメチン色素の J 会合体. 色材協会誌, 2006. 79(11): p. 503-510.
 Peet, J., et al., Efficiency enhancement in low-bandgap polymer solar cells by processing with alkane dithiols. Nature materials, 2007. 6(7): p. 497-500.
 Schlenker, C.W. and M.E. Thompson, The molecular nature of photovoltage losses in organic solar cells. Chemical Communications, 2011. 47(13): p. 3702-3716.
 Chen, C.-C., et al., Visibly transparent polymer solar cells produced by solution processing. ACS nano, 2012. 6(8): p. 7185-7190.
 Li, J. and N. Wu, Semiconductor-based photocatalysts and photoelectrochemical cells for solar fuel generation: a review. Catalysis Science & Technology, 2015. 5(3): p. 1360-1384.
 Verploegen, E., et al., Manipulating the morphology of P3HT–PCBM bulk heterojunction blends with solvent vapor annealing. Chemistry of Materials, 2012. 24(20): p. 3923-3931.
 Jørgensen, M., et al., Stability of polymer solar cells. Advanced materials, 2012. 24(5): p. 580-612.
 Zhao, J., et al., Phase diagram of P3HT/PCBM blends and its implication for the stability of morphology. The Journal of Physical Chemistry B, 2009. 113(6): p. 1587-1591.
 Ouyang, J., Solution-processed PEDOT: PSS films with conductivities as indium tin oxide through a treatment with mild and weak organic acids. ACS applied materials & interfaces, 2013. 5(24): p. 13082-13088.
 Lipomi, D.J., et al., Electronic properties of transparent conductive films of PEDOT: PSS on stretchable substrates. Chemistry of Materials, 2012. 24(2): p. 373-382.
 Lang, U., N. Naujoks, and J. Dual, Mechanical characterization of PEDOT: PSS thin films. Synthetic Metals, 2009. 159(5-6): p. 473-479.
 Burgelman, M., et al., Modeling thin‐film PV devices. Progress in Photovoltaics: Research and Applications, 2004. 12(2‐3): p. 143-153.
 Farooq, W., et al., Enhancing the absorption and power conversion efficiency of organic solar cells. International journal of engineering works, 2019. 6: p. 94-97.
 MacKenzie, R.C., et al., Modeling nongeminate recombination in P3HT: PCBM solar cells. The Journal of Physical Chemistry C, 2011. 115(19): p. 9806-9813.
 Hanfland, R., et al., The physical meaning of charge extraction by linearly increasing voltage transients from organic solar cells. Applied Physics Letters, 2013. 103(6): p. 063904.
 Deschler, F., et al., Increasing organic solar cell efficiency with polymer interlayers. Physical Chemistry Chemical Physics, 2013. 15(3): p. 764-769.
 MacKenzie, R.C., et al., Extracting microscopic device parameters from transient photocurrent measurements of P3HT: PCBM solar cells. Advanced Energy Materials, 2012. 2(6): p. 662-669.
 Koster, L.J.A., et al. Performance enhancement of poly (3-hexylthiophene): methanofullerene bulk-heterojunction solar cells. in Organic Photovoltaics VII. 2006. International Society for Optics and Photonics.
 Koster, L., V. Mihailetchi, and P. Blom, Ultimate efficiency of polymer/fullerene bulk heterojunction solar cells. Applied Physics Letters, 2006. 88(9): p. 093511.
 Apaydın, D.H., et al., Optimizing the organic solar cell efficiency: role of the active layer thickness. Solar energy materials and solar cells, 2013. 113: p. 100-105.
 Hanna, M. and A. Nozik, Solar conversion efficiency of photovoltaic and photoelectrolysis cells with carrier multiplication absorbers. Journal of Applied Physics, 2006. 100(7): p. 074510.
 Fabiano, S., et al., Role of photoactive layer morphology in high fill factor all-polymer bulk heterojunction solar cells. Journal of Materials Chemistry, 2011. 21(16): p. 5891-5896.
 Vandewal, K., et al., The relation between open‐circuit voltage and the onset of photocurrent generation by charge‐transfer absorption in polymer: fullerene bulk heterojunction solar cells. Advanced Functional Materials, 2008. 18(14): p. 2064-2070.