Z-Scheme Heterojunction of SnS₂/Bi₂WO₆ for Photoreduction of CO₂ to 100% Alcohol Products by Promoting the Separation of Photogenerated Charges.

ABSTRACT: Using sunlight to convert CO₂ into solar fuel is an ideal solution to both global warming and the energy crisis. The construction of direct Z-scheme heterojunctions is an effective method to overcome the shortcomings of single-component or conventional heterogeneous photocatalysts for photocatalytic CO₂ (carbon dioxide) reduction. In this work, a composite photocatalyst of narrow-gap SnS₂ and stable oxide Bi₂WO₆ were prepared by a simple hydrothermal method. The combination of Bi₂WO₆ and SnS₂ narrows the bandgap, thereby broadening the absorption edge and increasing the absorption intensity of visible light. Photoluminescence, transient photocurrent, and electrochemical impedance showed that the coupling of SnS₂ and Bi₂WO₆ enhanced the efficiency of photogenerated charge separation. The experimental results show that the electron transfer in the Z-scheme heterojunction of SnS₂/Bi₂WO₆ enables the CO₂ reduction reactions to take place. The photocatalytic reduction of CO₂ is carried out in pure water phase without electron donor, and the products are only methanol and ethanol. By constructing a Z-scheme heterojunction, the photocatalytic activity of the SnS₂/Bi₂WO₆ composite was improved to 3.3 times that of pure SnS₂.

SUBMITTER: Xu Y 

PROVIDER: S-EPMC9229445 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature