Highly Enhanced Full Solar Spectrum-Driven Photocatalytic CO2Reduction Performance in Cu2-xS/g-C3N4Composite: Efficient Charge Transfer and Mechanism Insight

An efficient full solar spectrum ultraviolet-visible-near infrared (UV-vis-NIR) light-driven Cu2-xS/g-C(3)N(4)composite photocatalyst is reported, which is fabricated by a facile solvothermal process for CO2 photoreduction into CO and CH4, as confirmed by product analysis and(13)C isotopic test. The composite exhibits superior full solar-spectrum-driven CO(2)photoreduction performance than pure Cu2-xS and g-C3N4, which is attributed to the efficient charge transfer due to the formation of intimate interface contact and S-C bond coupling between Cu2-xS and g-C(3)N(4)based on experimental analyses and theoretical calculations. In particular, the activities of the best composite for CO2 photoreduction into CO and CH4 under NIR light irradiation are about 2.6 times and 6.6 times higher than that of Cu2-xS, whereas no production is measured over g-C3N4. A possible mechanism of photocatalytic CO2 reduction is given based on in situ Fourier transform infrared (FTIR) analysis. This study paves the way to prepare carbon nitride-based photocatalysts with full-spectrum-responsive property for efficient CO2 photoreduction.

Automated summary

This study presents an efficient Cu2-xS/g-C(3)N(4) composite photocatalyst for CO2 photoreduction, with superior full solar-spectrum-driven performance attributed to the efficient charge transfer between Cu2-xS and g-C(3)N(4). The composite showed significantly higher activities compared to pure Cu2-xS and g-C3N4, paving the way for the development of carbon nitride-based photocatalysts for efficient CO2 photoreduction with full-spectrum-responsive property.