CdS/WO3 S-scheme heterojunction with improved photocatalytic CO2 reduction activity.

Abstract

The anthropogenic emission of CO2 in the environment affected our atmosphere, which caused a rapid change in the climate. It needs to reduce the excess CO2 from the environment to maintain sustainability and keep it green. In this work, we have fabricated a CdS decorated WO3 nanocomposite, improving the reduction ability of CO2 into CO and CH4 selectively in visible light. The construction of the heterojunction improved the stability of CdS with WO3. It synergistically resulted in ~7.7 times the higher yield of CO and 2.3 times the higher yield of CH4 than CdS using 20wt% CdS decorated WO3 nanocomposite in a mixture of N,N-dimethylformamide, triethylamine, and water in a 3:1:1 ratio. The 20wt% CdS on WO3 nanocomposite has proven an effective and selective photocatalyst with the relative yield of methanol up to four cycles. The nanocomposite photocatalysts were analyzed using instrumental techniques, such as XRD, XPS, HR-TEM, FTIR, TGA-DTA, UV-vis, PL spectroscopy, and PEC analysis.