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Metal halide perovskite quantum dots (Pe‐QDs) are of great interest in new‐generation photovoltaics (PVs). However, it remains challenging in the construction of conductive and intact Pe‐QD films to maximize their functionality. Herein, a ligand‐assisted surface matrix strategy to engineer the surface and packing states of Pe‐QD solids is demonstrated by a mild thermal annealing treatment after ligand exchange processing (referred to as “LE‐TA”) triggered by guanidinium thiocyanate. The “LE‐TA” method induces the formation of surface matrix on CsPbI₃ QDs, which is dominated by the cationic guanidinium (GA⁺) rather than the SCN⁻, maintaining the intact cubic structure and facilitating interparticle electrical interaction of QD solids. Consequently, the GA‐matrix‐confined CsPbI₃ QDs exhibit remarkably enhanced charge mobility and carrier diffusion length compared to control ones, leading to a champion …