Nanoscale spatial and time-resolved mapping in perovskite and organic solar cells: a multimodal technique to visualize the photoinduced charge dynamics

Recently, perovskite solar cells (PSCs) and organic solar cells (OSCs) have emerged as solution-processable photovoltaic (PV) technologies with certified power conversion efficiencies (PCEs) surpassing 26% and 20%, respectively. However, challenges such as charge generation, separation, transport, collection, and recombination at the nanoscale still exist in fully controlling and understanding the performance-limiting factors in the photoactive layers of OSC and PSC devices. Although several efforts have been reported to address the above phenomena, the origin of the nanoscale defects and how they lead to performance losses have not yet been fully understood. This perspective provides an in-depth discussion of nanoscale spatial and time-resolved mapping for OSCs and PSCs to understand their roles in improving PV performance. A comprehensive multimodal technique to map the charge carrier photodynamics at the nanoscale, such as charge generation, separation, transport, collection, and recombination in OSCs and PSCs, is presented, which has the potential to evaluate the photodynamics related to local heterogeneities in the active layers of the corresponding devices.