Laird Jamie S, Ravishankar Sandheep, Rietwyk Kevin J, Mao Wenxin, Bach Udo, Smith Trevor A
Centre of Excellence in Excitons, School of Chemistry, University of Melbourne, Parkville, Victoria, 3010, Australia.
IEK-5 Photovoltaik, Forschungszentrum Jülich, 52425, Jülich, Germany.
Small Methods. 2022 Sep;6(9):e2200493. doi: 10.1002/smtd.202200493. Epub 2022 Aug 16.
In this report, a large-area laser beam induced current microscope that has been adapted to perform intensity modulated photocurrent spectroscopy (IMPS) in an imaging mode is described. Microscopy-based IMPS method provides a spatial resolution of the frequency domain response of the solar cell, allowing correlation of the optoelectronic response with a particular interface, bulk material, specific transport layer, or transport parameter. The system is applied to study degradation effects in back-contact perovskite cells where it is found to readily differentiate areas based on their markedly different frequency response. Using the diffusion-recombination model, the IMPS response is modeled for a sandwich structure and extended for the special case of lateral diffusion in a back-contact cell. In the low-frequency limit, the model is used to calculate spatial maps of the carrier ambipolar diffusion length. The observed frequency response of IMPS images is then discussed.
在本报告中，描述了一种经过改进以在成像模式下执行强度调制光电流光谱（IMPS）的大面积激光束感应电流显微镜。基于显微镜的IMPS方法提供了太阳能电池频域响应的空间分辨率，允许将光电响应与特定界面、体材料、特定传输层或传输参数相关联。该系统被应用于研究背接触钙钛矿电池中的退化效应，发现它能够根据频率响应的显著差异轻松区分不同区域。使用扩散-复合模型，对三明治结构的IMPS响应进行建模，并针对背接触电池中的横向扩散特殊情况进行扩展。在低频极限下，该模型用于计算载流子双极扩散长度的空间图。然后讨论了IMPS图像观察到的频率响应。
