Enhanced photovoltaic performance and longevity of perovskite modules via interface engineering of transport layer

Abstract This research presents interfacial engineering of large-area perovskite solar modules. The quality of the interface between the electron transport layer (ETL) and the perovskite layer is studied, because it significantly affects the optoelectronic performance of large-area module devices. In large-area fabrication, film uniformity and interfacial quality are critical, as the ETL/perovskite interface governs both electron extraction and transport efficiency, while also affecting the uniformity and crystallinity of the perovskite. To overcome these issues, we use a picosecond laser technique (P1, P2, P3) to fabricate large-area modules, integrating monolithic cells in series. Planar SnO 2 and mesoporous TiO 2 ETL are prepared. Results show that meso-type ETL structures are better suited for large-area modules. The modules with meso-type TiO 2 exhibit fewer shunting issues and stronger emission in electroluminescence images. Photoluminescence mapping indicates improved structural uniformity of perovskite. The perovskite module with meso-type TiO 2 achieve a power conversion efficiency of 18.2% (4 cm 2 ) and maintain 80% of initial efficiency after 700 h.