Environmentally stable perovskite nanocrystals with improved photoelectrochemical performance enabled by poly nitroxide radical

Balancing the stability and interfacial charge transfer (CT) ability of perovskite nanocrystals (PNCs) are the most challenging issue confronting their practical application in photoelectrochemistry (PEC) fields. Here, an efficient surface capping strategy is introduced relying on a set of air-stable nitroxide-based organic radical polymers with well-matched energy levels towards CsPbBr3 nanocrystals. The native ligand oleyl amine and oleic acid were readily replaced by radical polymers because of their high-affinity properties. The resulting radical polymer coated PNCs exhibit exceptional tolerance to water, thermal, and UV illumination with remarkable CT processes. The versatility and immense practical utility of such stable PNCs-radical core/shell structure are showcased by the halogen exchange between PNCs/radical and aryl chlorides at ambient temperature, demonstrating superb reduction ability of this complex. Besides, this strategy was also employed to improve the power conversion efficiency and stability of PNCs based solar cells. This approach imparts exceptional photoelectrochemical sta-bility and catalytic activity to the nanocrystals with excellent interfacial CT efficiency.