Plasma-induced defect engineering: Boosted the reverse water gas shift reaction performance with electron trap

Abstract

The reverse water gas shift reaction is a promising approach to solve the problem of excessive CO2 emission and energy shortage. However, insufficient charge separation efficiency of numerous semiconductor photocatalysts hamper their CO2 photoreduction performance. Defect engineering is considered as a desired method to tackle that shortcoming by the boosting the electron capture process. Herein, the sulfur vacancies-rich CdIn2S4 (VS-CdIn2S4) was synthesized by an efficient low-temperature plasma-enhanced technology. The outstanding VS-CdIn2S4 shows a more excellent CO formation rate of 103.6 μmol g−1 h−1 comparing that of traditional CdIn2S4 (31.36 μmol g−1 h−1). The density function theory (DFT) calculation reveals the sulfur vacancy is the center of electron capture. Moreover, the formed defect level after introduce of surface vacancy effectively optimizes the light absorption propertie of the prepared material. Thus, the enhanced photocatalytic CO2 reduction performance can be attributed to the double improvement of light absorption and carrier separation. This work provides a novel and facile strategy to mediate carriers’ movement behavior via defect engineering for high-efficient CO2 photoreduction.