Enhancing Efficiency of Industrially‐Compatible Monolithic Perovskite/Silicon Tandem Solar Cells with Dually‐Mixed Self‐Assembled Monolayers

Abstract The antisolvent‐assisted spin‐coating still lags behind the thermal evaporation method in fabricating perovskite films atop industrially textured silicon wafers in making monolithic perovskite/silicon solar cells (P/S‐TSCs). The inhomogeneity of hole‐selective self‐assembled monolayers (SAMs) often arises from the insufficient bonding between hygroscopic phosphonic acid anchors and metal oxide. To address this, a mixed‐SAM strategy (Mx‐SAM) is proposed to enhance the adsorption energy of SAMs on the ITO surface, facilitate the formation of dense and humidity‐resistant hole‐selective layer (HSL) on substrates, and improve hole transport capabilities. With the aid of the Mx‐SAM strategy, the optimized wide‐bandgap PSCs achieved an impressive power conversion efficiency (PCE) of 22.63% with an exceptionally high fill factor ( FF ) of 86.67% using the 1.68 eV perovskite. Moreover, they exhibited enhanced stability under damp‐heat conditions (ISOS‐D‐3, 85% RH, 85 °C) with a T 90 of 900 h for encapsulated PSCs, representing one of the best performances for wide‐bandgap PSCs. When further extending the Mx‐SAM strategy to making P/S‐TSCs using silicon wafers from industry, a remarkable efficiency of 28.07% is reached while upholding outstanding reproducibility. This strategy holds significant promise for the feasibility of fabricating industrially‐compatible P/S‐TSCs.