Hydrogenation of CO2 to Methanol on CeOx/Cu(111) and ZnO/Cu(111) Catalysts: Role of the Metal–Oxide Interface and Importance of Ce3+ Sites
Hydrogenation of CO2 to Methanol on CeOx/Cu(111) and ZnO/Cu(111) Catalysts: Role of the Metal–Oxide Interface and Importance of Ce3+ Sites
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DOI：
10.1021/acs.jpcc.5b12012
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发表时间：
2016-01
影响因子：
3.7
通讯作者：
S. Senanayake;P. Ramírez;I. Waluyo;S. Kundu;K. Mudiyanselage;Zongyuan Liu;Z. G. Liu;S. Axnanda
中科院分区：
文献类型：
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作者：
S. Senanayake;P. Ramírez;I. Waluyo;S. Kundu;K. Mudiyanselage;Zongyuan Liu;Z. G. Liu;S. Axnanda
金属和氧化物（CeOx-Cu和ZnO-Cu）之间的界面对于通过CO2加氢（CO2 + 3 H2 → CH 3OH + H2O）生产甲醇至关重要。CeOx或ZnO纳米颗粒在Cu（111）上的沉积，θoxi < 0.3单层，产生用于甲醇合成的高活性催化剂。催化剂的活性顺序为：Cu（111）< ZnO/Cu（111）< CeOx/Cu（111）。CO2 → CH 3OH转化的表观活化能从Cu（111）上的25 kcal/mol降低到ZnO/Cu（111）上的16 kcal/mol和CeOx/Cu（111）上的13 kcal/mol。采用常压X射线光电子能谱（AP-XPS）和红外反射吸收谱（AP-IRRAS）研究了高活性CeOx-Cu（111）界面的表面化学。这两种技术都指出在反应过程中会形成甲酸盐（HCOO-）和羧酸盐（CO2δ−）。我们的研究结果表明，富含Ce 3+位点的催化剂的活性状态稳定了CO2δ−物种，这是一个重要的中间体。
The role of the interface between a metal and oxide (CeOx–Cu and ZnO–Cu) is critical to the production of methanol through the hydrogenation of CO2 (CO2 + 3H2 → CH3OH + H2O). The deposition of nanoparticles of CeOx or ZnO on Cu(111), θoxi < 0.3 monolayer, produces highly active catalysts for methanol synthesis. The catalytic activity of these systems increases in the sequence: Cu(111) < ZnO/Cu(111) < CeOx/Cu(111). The apparent activation energy for the CO2 → CH3OH conversion decreases from 25 kcal/mol on Cu(111) to 16 kcal/mol on ZnO/Cu(111) and 13 kcal/mol on CeOx/Cu(111). The surface chemistry of the highly active CeOx–Cu(111) interface was investigated using ambient pressure X-ray photoemission spectroscopy (AP-XPS) and infrared reflection absorption spectroscopy (AP-IRRAS). Both techniques point to the formation of formates (HCOO–) and carboxylates (CO2δ−) during the reaction. Our results show an active state of the catalyst rich in Ce3+ sites which stabilize a CO2δ− species that is an essential inter...