Stabilizing Efficient Perovskite/Silicon Tandem Solar Cells With Amorphous and Asymmetric Hole-Selective Contacts

Perovskite/silicon tandem solar cells (TSCs) hold great promise for next-generation photovoltaics, yet uneven coverage and thermal instability of self-assembled hole-selective contacts hinder their commercialization. Here, we introduce ZF6, an amorphous molecular contact with an asymmetric π-extended structure, featuring a dimethylindenocarbazole core and carbazole substitution. ZF6 exhibits rapid and robust adsorption on transparent conductive substrates, achieving uniform coverage and exceptional thermal stability. Its optimal energy level alignment and enhanced carrier extraction efficiency are compatible with various bandgap perovskites. ZF6-based double-junction perovskite/silicon TSCs achieve a reverse-scan power conversion efficiency (PCE) of 34.02% (certified 32.81% at NREL) with improved operational stability, retaining over 97% and 87% of initial efficiency after 1000 h of maximum power point tracking at 45°C and 85°C, respectively. We also fabricate triple-junction perovskite/perovskite/silicon TSCs, achieving a certified steady-state PCE of 30.42%, which represents the highest-performing triple-junction perovskite-based TSCs reported to date. This work establishes a novel design strategy for robust molecular contacts, advancing efficient and durable perovskite-based tandem photovoltaics.