抄録
Abstract
This study introduces a multifunctional coordination approach to enhance wide bandgap (WBG) tin (Sn) perovskite solar cells (PSCs) by incorporating a naturally derived Vitamin H (Biotin) complex into the perovskite precursor. The Biotin complex exhibits strong chemical interaction with Sn2+ via its ureido ring (CO, NH), valeric acid chain (COO−), and tetrahydrothiophene (SC) functionalities. This multidentate interaction further helps to regulate crystal growth kinetics, resulting in compact, pinhole‐free films with enhanced surface homogeneity. Furthermore, Biotin effectively passivates uncoordinated Sn sites, mitigates Sn2+ oxidation, and suppresses antisite defects, thereby reducing non‐radiative recombination and ion migration. As a result, the optimized device demonstrates a record‐high power conversion efficiency of 12.8% (independently certified at 12.5%) and an open‐circuit voltage (Voc) of 1.03 V for WBG Sn PSCs. Notably, the device exhibits outstanding ambient stability, retaining almost 80% of its initial efficiency after 1460 h of storage without encapsulation, highlighting the potential of the Biotin complex for high‐performance and durable lead‐free perovskite photovoltaics.
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