Charge accumulations and electron recombination at the interfaces between perovskites and charge transporting materials are two critical factors significantly hindering the power conversion efficiency (PCE) and device stability of wide-bandgap perovskite solar cells (WBG PSCs). Herein, we tailor-made a self-assembled molecule (SAM), termed XS13, featuring an enlarged π-donor and a π-linker, to regulate the interface carrier dynamics in ∼1.8 eV WBG PSCs. Ultrafast spectroscopy clearly demonstrated that the XS13 facilitated the rapid extraction and transfer of photo-generated holes compared to the reference SAM-2PACz. Consequently, WBG PSCs based on XS13 achieved an outstanding PCE of up to 19.20 %, surpassing that of control devices (16.41 %). Furthermore, XS13-based WBG PSCs exhibited a remarkable suppression of light/electricity-induced halide ions migration, leading to significantly improved device stability. Our findings offer a new strategy for the rational design of hole transporting molecules with controlled properties to enhance device performance of PSCs.
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