%P 1119-1130
%T Enhancement of organic solar cell efficiency by altering the zinc oxide photoanode nanostructure morphology
%I Springer Medizin
%V 12
%A Z. Samavati
%A A. Samavati
%A A.F. Ismail
%A T.N. Borhani
%A M. Velashjerdi
%A B.G. Eisaabadi
%A A. Rostami
%A M.H.D. Othman
%A A. Awang
%D 2022
%N 6
%R 10.1007/s40097-021-00453-2
%O cited By 4
%J Journal of Nanostructure in Chemistry
%L scholars16161
%X The current paper examines the effects of zinc oxide nanostructure configurations, as photo-anode formations of organic solar cells, on the performance of power conversion. To this end, some experiments were conducted during which a near band edge emission red shift of ~ 0.11 eV from nanoparticles to vertically oriented nano-rods was observed. This bandgap narrowing promotes transferring of photo-excited electrons towards the conduction band of photo-anode. A ~ 48 decrease in the deep level emission intensity revealed a smaller non-radiative waves emission due to lower level of crystal disorder. Using vertically oriented zinc oxide nanorods as photo-anodes, the photovoltaic efficiency of the organic solar cell improved considerably. The nano-rod-structured photo-anodes showed a 0.22 V rise in the open-circuit voltage, from 0.76 to 0.98 V, and a 2.08 times increment in the overall conversion performance, compared to the zinc oxide nanoparticle-structured photo-anodes. This superior performance is attributed to a greater chance of charge recombination and light-trapping in the cells, more efficient light absorption, and high level of crystallinity that grants easier electron mobility for vertically oriented zinc oxide nanorods. Moreover, a lower charge-transfer resistance (0.85 Ω) was achieved due to better electro-catalytic action for oxygen reduction for vertical nanorods compared to the other two zinc oxide configurations (1.62 Ω and 4.06 Ω). This boosted the cell performance by increasing the short-circuit current density (JSC). The fabricated solar cell may contribute to sustainable and environmentally friendly electricity generation process through reducing the consumption of non-renewable energy sources. © 2021, The Author(s), under exclusive licence to Islamic Azad University.