Oxygen vacancies induced special CO2 adsorption modes on Bi2MoO6 for highly selective conversion to CH4
Oxygen vacancies induced special CO2 adsorption modes on Bi2MoO6 for highly selective conversion to CH4
复制标题
氧空位在 Bi2MoO6 上诱导特殊的 CO2 吸附模式，用于高选择性转化为 CH4
DOI：
10.1016/j.apcatb.2019.118088
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Ye Jinhua
中科院分区：
文献类型：
--
作者：
Yang Xianglong;Wang Shengyao;Yang Nan;Zhou Wei;Wang Pei;Jiang Kai;Li Shu;Song Hui;Ding Xing;Chen Hao;Ye Jinhua
寻找合适的具有超高选择性从CO2生成CH4的光催化剂是人工光催化领域的巨大挑战。在此，在可见光下，相对于缺氧的 Bi2MoO6，实现了有效的 CO2 光转化为 CH4，选择性高达 96.7%。各种表征和DFT计算表明，Bi2MoO6的{001}表面上精心设计的氧空位（OV）不仅可以增强光捕获和e--/h+分离，而且有利于以特殊的双齿碳酸盐模式吸收CO2，这在热力学上支持中间体*CO进一步加氢生成CH4。基于原位红外光谱分析，找出了含OVs和不含OVs的Bi2MoO6上两种途径的CO2吸附模式和反应中间体。还提出了高选择性转化CH4的合理光催化机理。这项工作为 OV 在选择性 CO2 光转化中的作用提供了新的见解，并为设计高效的 CH4 进化系统铺平了道路。
Search for suitable photocatalysts with ultrahigh selective generation of CH4from CO2is a great challenge in artificial photocatalysis. Herein, effective CO2photoconversion to CH4with high selectivity up to 96.7% is achieved over oxygen-deficient Bi2MoO6under visible-light. Various characterizations and DFT calculations indicated that well-designed oxygen vacancies (OVs) on the {001} surface of Bi2MoO6can not only enhance light harvesting ande−-/h+separation, but favor CO2adsorption in a special bidentate carbonate mode, which thermodynamically supports the further hydrogenation of intermediate *CO to generate CH4. Based on thein-situinfrared spectroscopy analysis, the CO2adsorption modes and reaction intermediates of two pathways over Bi2MoO6with or without OVs were figured out. The reasonable photocatalytic mechanism for highly selective conversion to CH4was also proposed. This work provides new insights to the role of OVs in selective CO2photoconversion, and paves ways to design efficient CH4evolution systems.