Overturning CO 2 Hydrogenation Selectivity by Tailoring the Local Electron Density of Ru/CeO 2 Catalysts

作者：Yu Xie, Jianjun Chen, Junjie Wen, Zonglin Li, Fangxian Cao, Sai Zhang, Qiming Sun, Ping Ning, Qiulin Zhang, Jiming Hao · 发表于：ACS Catalysis · 年份：2024 · DOI：10.1021/acscatal.4c03094 · 被引用次数：45 · 研究领域：Catalysts for Methane Reforming、CO2 Reduction Techniques and Catalysts、Carbon dioxide utilization in catalysis

Flexible tuning of the CO 2 hydrogenation selectivity through properly designed catalysts to obtain desired high-added-value products is a promising strategy for addressing environmental and energy issues but also a huge challenge. Herein, the CO 2 hydrogenation selectivity over the commonly used Ru/CeO 2 methanation catalysts was facilely overturned from ∼99% CH 4 to 100% CO by tailoring the local electron density of Ru through electronic interaction induced by electron acceptors (Bi, In, Sn, etc.). Systematically, in situ spectroscopic characterizations and DFT calculations reveal that owing to the electron-withdrawing role of the electron acceptor, Ru sites lose more charges than the unmodified catalyst, which weakens the binding strength of carbonyl to Ru sites and further induces the imbalance reaction energy barrier for carbonyl and formate intermediates. Thus, the original parallel reaction processes involving CH 4 generation (carbonyl route and formate route) are transformed into the preferential desorption of CO, finally acquiring opposite selectivity. Importantly, such an electronic interaction is general for overturning product selectivity and can be extended to other Ru catalysts and Ni catalysts. This discovery may offer a promising way to develop CO 2 hydrogenation catalysts with controllable product selectivity.