Yu-Ching HuangSheng-Wen HuangChia-Feng LiShih-Han HuangFENG-YU TSAIWEI-FANG SU2024-12-242024-12-242025-01-0113858947https://www.scopus.com/record/display.uri?eid=2-s2.0-85211039336&origin=resultslisthttps://scholars.lib.ntu.edu.tw/handle/123456789/724349Perovskite/silicon tandem solar cells have emerged as a highly promising strategy for surpassing the Shockley–Queisser limit. Among these tandem solar cells, the wide-bandgap perovskite plays a key role in highly efficient tandem solar cells. However, the wide bandgap perovskite material suffers from considerable voltage loss due to a high trap density and phase instability under light illumination. In this study, we present a comprehensive set of optimization procedures designed to enhance the power conversion efficiency of methylammonium-free (MA-free) wide-bandgap perovskites. Following this procedure, the opaque MA-free wide-bandgap perovskite solar cells demonstrate an impressive efficiency of 22.11 % with a minimal open-circuit voltage deficit of 0.47 V. Moreover, the efficiency of the semi-transparent wide-bandgap perovskite solar cells reached 19.21 %, and these semi-transparent cells were subsequently integrated into a 4-terminal perovskite/Si tandem solar cell, yielding a remarkable efficiency of 29.98 %. Our study paves a facile way towards highly efficient wide-bandgap perovskite solar cells for the application of semi-transparent and tandem solar cells.falseLattice strain-induced phase segregationMA-freePerovskiteTandemWide-bandgap[SDGs]SDG7journal article10.1016/j.cej.2024.1582722-s2.0-85211039336