Efficient photocatalytic reduction of CO₂ into value-added chemical fuels has been a thorny, challenging and long-term project in the environmental/energy fields due to the low efficiency, especially in the inorganic aqueous environment. In this report, we present a facial approach to modify CdS with Co(II) species through controlling decarboxylation of the Co-EDTA precursor for improved CO₂ reduction. Performance evaluation and microstructure characterization reveal that the resulted tetra-coordinated Co(II) modified CdS exhibits the most optimized CO evolution rate of 9.8 μmol h⁻¹ (i.e., 392 μmol h⁻¹ g_(catalyst)⁻¹ with TOF of 7.94 h⁻¹) in aqueous solution under visible light, where the competitive hydrogen evolution reaction is significantly inhibited. Further investigation implies that the fully utilized Co(II) active sites, the tetra-coordinated Co(II) species, the favorable interaction between CO₂ and Co(II) sites and efficient charge transferring ensured the high efficiency and improved selectivity. This work would provide a good strategy for the structure engineering of catalytic site to improve photocatalytic CO₂ reduction.

由于效率低，特别是在无机水性环境中，有效地将CO ₂光催化还原为增值的化学燃料一直是环境/能源领域中棘手，具有挑战性和长期的项目。在这份报告中，我们提出了一种通过控制Co-EDTA前体的脱羧作用来改善Co ₂还原的面部修饰Co（II）物种的CdS的方法。性能评估和微观结构表征表明，得到的四配位Co（II）修饰的CdS表现出最优化的CO释放速率，为9.8μmolh ^-1（即392μmolh ^-1  g _{（催化剂）}^-1，TOF为7.94 h ^-1）在可见光下的水溶液中，竞争性放氢反应被显着抑制。进一步的研究表明，充分利用的Co（II）活性位点，四配位的Co（II）物种，CO ₂和Co（II）位点之间的良好相互作用以及有效的电荷转移确保了高效率和更高的选择性。这项工作将为催化位点的结构工程改善光催化CO ₂还原提供良好的策略。