C(sp ³ )-H Bond Activation by Perovskite Solar Photocatalyst Cell

摘要： Inspired by the efficient perovskite solar cells, we developed a three-component hybrid perovskite-based solar photocatalyst cell - NiOx/ FAPbBr3/TiO2 - for C(sp3)-H bonds activation with high selectivity (~90%) and high conversion rates (3800 μmol g-1 h-1) under ambient conditions. Time-resolved spectroscopy on our photocatalytic cell reveals efficient exciton dissociation and charge separation, where TiO2 and NiOx serve respectively as the electron and hole transporting layers. The photo-generated charge carriers, injected into TiO2 and NiOx drive the challenging C-H activation reaction via the synergetic effects of their band alignment relative to FAPbBr3. The reaction pathway is investigated by controlling the free radical formation and we find that C-H activation is mainly triggered by hole oxidation. Besides aromatic alkanes, also C(sp3)-H bond in cycloalkanes can selectively be oxidised. This work demonstrates a generic strategy for engineering high-performance photocatalysts based on the perovskite solar cell concept.