Visible-light-driven CO2 reduction yielding commodity chemicals such as ethylene holds tremendous potentials for achieving a carbon-neutral circular economy in the energy and chemical industry. Despite the success of electrochemical CO2 reduction, efficient and selective ethylene generation has not been achieved by photocatalytic means because the intermediate dimerization fails to occur on existing photocatalysts. Here, we first demonstrate that the presence of sulfur vacancies in CdS (Sv-CdS) lead to reduced Cd-Cd distance and charge enrichment on Cd atoms. This structural relaxation and associated electronic structure tuning endow successful *CHO dimerization and hence ethylene generation. The photocatalyst can be optimized by coating Sv-CdS with ZIF-8 to form a core-shell structure, which presents further lowered energy barrier for both *CO hydrogenation and *CHO dimerization. With these combined intermediate manipulation strategies, the optimized photocatalyst exhibits a record-high ethylene selectivity of 12.8 % at a production rate of 0.8 μmol g−1 h−1.
- CO photoreduction
- Combined intermediate manipulation
- Intermediate dimerization
- Structural relaxation
ASJC Scopus subject areas
- Environmental Science (all)
- Process Chemistry and Technology