1. Constructing an Active Sulfur-Vacancy-Rich Surface for Selective *CH 3 -CH 3 Coupling in CO 2 -to-C 2 H 6 Conversion With 92% Selectivity.
- Author
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Yang X, Ren L, Chen Z, Li H, and Yuan Y
- Abstract
To achieve high selectivity in photocatalytic CO
2 reduction to C2+ products, increasing the number of CO2 adsorption sites and lowering the energy barriers for key intermediates are critical. A ZnIn2 S4 (ZIS)/MoO3-x (Z-M) photocatalyst is presented, in which plasmonic MoO3-x generates hot electrons, creating a multielectron environment in ZIS that facilitates efficient C─C coupling reactions. Density functional theory (DFT) calculations reveal that MoO3-x reduces the formation energy of sulfur vacancies (SV ) in ZIS, thereby enhancing CO2 adsorption and activation. The SV -rich surface lowers the energy barrier for forming HCOO* to -0.33 eV whereas the energy barrier for forming* COOH is 0.77 eV. Successive hydrogenation of HCOO* leads to* CH2 , which converts to* CH3 with an energy barrier of -0.63 eV. The energy barrier for* CH3 -CH3 coupling is 0.54 eV, which is lower than the 0.73 eV for* CH2 -CH2 coupling to form* C2 H4 . Thus, Z-M preferentially produces C2 H6 over C2 H4 . Under visible light, Z-M achieves a CO2 -to-C2 H6 conversion rate of 467.3 µmol g-1 h-1 with 92.0% selectivity. This work highlights the dual role of plasmonic photocatalysts in enhancing CO2 adsorption and improving C2+ production in CO2 reduction., (© 2024 Wiley‐VCH GmbH.)- Published
- 2024
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