2019 Volume 62 Issue 1 Pages 9-14
Perovskite solar cells (PSCs) are the most promising next generation photovoltaic technology, whose energy conversion efficiency has increased rapidly in a few years. However, in contrast to the rapid increase in efficiency, the fundamental understanding of the device working principles has hardly progressed. It is therefore important to clarify the details of photovoltaic conversion processes for a deeper understanding of the energy loss mechanism. Here, we present a study of carrier separation processes in the PSCs by operando profiling of electrical potential distribution using the cross-sectional Kelvin probe force microscopy. We found that the position of the carrier separation in the PSCs depended on the device structures and the composition of the perovskite film. Our experimental findings showed the importance of the hetero-interfaces in the photovoltaic conversion processes.
