Enhancing Crystallization and Optimizing the Buried Interface via Hydrophobic Trifluoromethyl Molecules for Efficient Sn–Pb Perovskite and All‐Perovskite Tandem Solar Cells

ABSTRACT Hybrid tin‐lead (Sn–Pb) perovskites, with bandgaps tunable down to 1.25 eV, hold great promise for high‐efficiency photovoltaics. However, their performance is often hampered by the buried interface defects and instability induced by the commonly used hole‐transport layer (HTL), Poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), which suffers from intrinsic hygroscopicity and non‐uniformity. Here, we introduce a multifunctional molecule, (S)‐methyl 2‐amino‐2‐(3‐fluoro