Embedding CsPbBr3 perovskite quantum dots into mesoporous TiO2 beads as an S-scheme heterojunction for CO2 photoreduction

Heterojunction engineering, especially S-scheme heterojunction, has been recognized as a promising way to explore photocatalysts with boosted charge separation and CO2 photoreduction. Herein, we develop a CsPbBr3@mesoporous TiO2 beads (MTB) S-scheme heterojunction by embedding CsPbBr3 perovskite quantum dots (QDs) into the pores of MTB. The intimate interfacial interaction and staggered band structures promised the S-scheme charge transfer route, as confirmed by X-ray photoelectron spectra (XPS), electron spin resonance (ESR), etc. The 0.15CsPbBr(3)@MTB (15 wt% of CsPbBr3) hybrid exhibited a remarkable yield of 145.28 mu mol g(-1)h(-1) for CO2 photoreduction under simulated sunlight irradiation, which was 4.64 and 3.49-fold enhancement than the pristine MTB and CsPbBr3, respectively. This study provides useful guide towards the design of perovskite-based heterojunctions for photocatalytic applications.

Automated summary

In this study, a CsPbBr3@mesoporous TiO2 beads (MTB) S-scheme heterojunction was developed, which showed boosted charge separation and CO2 photoreduction. The intimate interfacial interaction and staggered band structures of CsPbBr3 quantum dots embedded in MTB provided an efficient charge transfer route. The hybrid of 0.15CsPbBr3@MTB exhibited a remarkable enhancement in CO2 photoreduction, with a yield of 145.28 μmol g(-1)h(-1) under simulated sunlight irradiation, which was 4.64 and 3.49-fold higher than that of pristine MTB and CsPbBr3, respectively. This study provides valuable guidance for the design of perovskite-based heterojunctions for photocatalytic applications.