Unique S-scheme heterojunctions in self-assembled TiO(2)/CsPbBr(3) hybrids for CO(2) photoreduction

Exploring photocatalysts to promote CO(2) photoreduction into solar fuels is of great significance. We develop TiO(2)/perovskite (CsPbBr(3)) S-scheme heterojunctions synthesized by a facile electrostatic-driven self-assembling approach. Density functional theory calculation combined with experimental studies proves the electron transfer from CsPbBr(3) quantum dots (QDs) to TiO(2), resulting in the construction of internal electric field (IEF) directing from CsPbBr(3) to TiO(2) upon hybridization. The IEF drives the photoexcited electrons in TiO(2) to CsPbBr(3) upon light irradiation as revealed by in-situ X-ray photoelectron spectroscopy analysis, suggesting the formation of an S-scheme heterojunction in the TiO(2)/CsPbBr(3) nanohybrids which greatly promotes the separation of electron-hole pairs to foster efficient CO(2) photoreduction. The hybrid nanofibers unveil a higher CO(2)-reduction rate (9.02 μmol g(–1) h(–1)) comparing with pristine TiO(2) nanofibers (4.68 μmol g(–1) h(–1)). Isotope ((13)CO(2)) tracer results confirm that the reduction products originate from CO(2) source.