Regulating hot-carrier dynamics via indium anchoring for highly stable CO2 photoreduction on CsPbBr3 nanocrystals

Hot carrier-lattice coupling driven by Br migration defects is identified as the intrinsic origin of CsPbBr 3 PNCs instability. • An In-anchoring strategy suppresses Br migration, passivates defects, and prolongs the hot carrier lifetime by ∼99%. • In-anchored CsPbBr 3 PNCs achieves a cumulative CO yield of 2.2 mmol g –1 over 60 h , 14.85 times higher than CsPbBr 3 PNCs. CsPbBr 3 perovskite nanocrystals (PNCs) demonstrate exceptional photocatalytic potential in CO 2 conversion through superior light harvesting and multi-exciton generation. However, their practical application is fundamentally hindered by structural instability that compromises carrier utilization. This study, using femtosecond transient absorption spectroscopy and temperature-dependent photoluminescence, reveals that dynamic coupling between hot carriers and lattice vibrations drives structural degradation via localized phonon excitations. To address this, we engineered indium (In)-anchored CsPbBr 3 PNCs by targeted modification of surface Pb centers. The In-anchoring passivates defect-associated empty p-orbitals while prolonging the hot carrier lifetime by 98.86%. Furthermore, the introduced In ions induce electronic localization, which suppresses phonon-driven lattice vibrations. As a result, charge separation and transport are dramatically enhanced, leading to a significant improvement in both CO 2 reduction activity and stability. In contrast to CsPbBr 3 PNCs, which completely deactivate within 20 h, In-anchored CsPbBr 3 PNCs maintain stability over long-term operation for up to 60 h, while simultaneously exhibiting a 14.85-fold enhancement in CO yield. This study establishes a fundamental strategy for stabilizing perovskite photocatalysts by regulating hot carrier-lattice interactions, offering new insights into the design of high-performance CO 2 reduction systems. Download: Download high-res image (188KB) Download: Download full-size image This work establishes an indium-anchoring strategy that regulates carrier-lattice interactions, suppresses defect-induced degradation, prolongs hot-carrier lifetime, and simultaneously enhances the photocatalytic activity and stability of CsPbBr 3 perovskite nanocrystals.