Lee Jongjin, Kong Jaemin
Department of Physics and Research Institute for Green Energy Convergence Technology (RIGET), Gyeongsang National University, Jinju, 660-701, South Korea.
Department of Chemical and Biomolecular Engineering, NYU Tandon School of Engineering, 6 MetroTech Center, Brooklyn, NY, 11201, USA.
Nanoscale Res Lett. 2018 Aug 1;13(1):228. doi: 10.1186/s11671-018-2639-6.
Cross-sectional potential distribution of high open-circuit voltage bulk heterojunction photovoltaic device was measured using Kelvin probe force microscopy. Potential drop confined at cathode interface implies that photo-active layer is an effective p-type semiconductor. Potential values in field-free region show wide variation according to log-normal distribution. This potential dip prone to have holes captured during the diffusive motion, which can increase bimolecular recombination, while potential gradient in depletion region makes this potential dip smaller and the captured holes easily escape from dip region by Schottky barrier lowering.
