Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China.
J Chem Phys. 2020 Oct 28;153(16):164306. doi: 10.1063/5.0026692.
Photocatalytic hydrogenation of carbon dioxide (CO) to produce value-added chemicals and fuel products is a critical routine to solve environmental issues. However, developing photocatalysts composed of earth-abundant, economic, and environmental-friendly elements is desired and challenging. Metal oxide clusters of subnanometer size have prominent advantages for photocatalysis due to their natural resistance to oxidation as well as tunable electronic and optical properties. Here, we exploit 3d transition metal substitutionally doped ZnO clusters for CO hydrogenation under ultraviolet light. By comprehensive ab initio calculations, the effect of the dopant element on the catalytic behavior of ZnO clusters is clearly revealed. The high activity for CO hydrogenation originates from the distinct electronic states and charge transfer from transition metal dopants. The key parameters governing the activity and selectivity, including the d orbital center of TM dopants and the energy level of the highest occupied molecular orbital for the doped ZnO clusters, are thoroughly analyzed to establish an explicit electronic structure-activity relationship. These results provide valuable guidelines not only for tailoring the catalytic performance of subnanometer metal oxide clusters at atomic precision but also for rationally designing non-precious metal photocatalysts for CO hydrogenation.
光催化二氧化碳（CO）加氢转化为有价值的化学品和燃料产品是解决环境问题的关键途径。然而，开发由丰富、经济和环保元素组成的光催化剂仍然是一个具有挑战性的需求。亚纳米尺寸的金属氧化物团簇由于其天然的抗氧化性以及可调谐的电子和光学性质，在光催化中具有显著的优势。在这里，我们利用 3d 过渡金属取代掺杂 ZnO 团簇在紫外光下进行 CO 加氢反应。通过综合的第一性原理计算，清楚地揭示了掺杂元素对 ZnO 团簇催化行为的影响。CO 加氢反应的高活性源于过渡金属掺杂剂的独特电子态和电荷转移。深入分析了决定活性和选择性的关键参数，包括 TM 掺杂剂的 d 轨道中心和掺杂 ZnO 团簇的最高占据分子轨道能级，以建立明确的电子结构-活性关系。这些结果不仅为原子精度调控亚纳米金属氧化物团簇的催化性能提供了有价值的指导，也为合理设计 CO 加氢用非贵金属光催化剂提供了指导。
