Unique S-scheme heterojunctions in self-assembled TiO<sub>2</sub>/CsPbBr<sub>3</sub> hybrids for CO<sub>2</sub> photoreduction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 32929077.
- Also identified by DOI 10.1038/s41467-020-18350-7 and PMC identifier 7490390.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Exploring photocatalysts to promote CO<sub>2</sub> photoreduction into solar fuels is of great significance. We develop TiO<sub>2</sub>/perovskite (CsPbBr<sub>3</sub>) 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<sub>3</sub> quantum dots (QDs) to TiO<sub>2</sub>, resulting in the construction of internal electric field (IEF) directing from CsPbBr<sub>3</sub> to TiO<sub>2</sub> upon hybridization. The IEF drives the photoexcited electrons in TiO<sub>2</sub> to CsPbBr<sub>3</sub> upon light irradiation as revealed by in-situ X-ray photoelectron spectroscopy analysis, suggesting the formation of an S-scheme heterojunction in the TiO<sub>2</sub>/CsPbBr<sub>3</sub> nanohybrids which greatly promotes the separation of electron-hole pairs to foster efficient CO<sub>2</sub> photoreduction. The hybrid nanofibers unveil a higher CO<sub>2</sub>-reduction rate (9.02 μmol g<sup>-1</sup> h<sup>-1</sup>) comparing with pristine TiO<sub>2</sub> nanofibers (4.68 μmol g<sup>-1</sup> h<sup>-1</sup>). Isotope (<sup>13</sup>CO<sub>2</sub>) tracer results confirm that the reduction products originate from CO<sub>2</sub> source.