In Situ-Illuminated X-Ray Photoelectron Spectroscopy Investigation of S-Scheme Ta2O5/ZnIn2S4 Core-Shell Hybrid Nanofibers for Highly Efficient Solar-Driven CO2 Overall Splitting

Exploring and designing highly efficient solar-driven CO2 overall splitting photocatalysts toward carbon neutrality is still challenging. Herein, a novel core-shell Ta2O5/ZnIn2S4 heterojunction photocatalyst is fabricated where ZnIn2S4 nanosheets are deposited on mesoporous Ta2O5 nanofibers via electrospinning and hydrothermal methods. In situ-illuminated X-ray photoelectron spectra analysis and density functional theory calculation imply that the photoelectrons in ZnIn2S4 can transfer to Ta2O5 though a 2D/1D interface, accelerating the separation of photo-generated electron-hole pairs driven by the built-in electric field under illumination, coupling the S-scheme charge transfer mechanism. As a result, the total yield of CO2 overall splitting (including CO and CH4) over ZISTO0.1 is about 4.1 and 5.74 times that of pristine Ta2O5 nanofibers and ZnIn2S4 nanosheets, respectively. This work may pave a promising strategy of designing heterojunction photocatalysts with S-scheme pathways toward solar fuel generation.

Automated summary

This article presents a novel core-shell Ta2O5/ZnIn2S4 heterojunction photocatalyst and demonstrates its high efficiency in solar-driven CO2 overall splitting. The efficient charge separation of photo-generated electron-hole pairs is achieved through the 2D/1D interface and the built-in electric field, resulting in a significantly enhanced yield of CO2 splitting products.