文献类型：期刊文献

中文题名：Ni/Ce0.75Zr0.25O2界面催化CO2甲烷化密度泛函理论研究

英文题名：Density functional theory study of catalytic methanation of CO_2 at the Ni/Ce_(0.75)Zr_(0.25)O_2 interface

作者：彭超[1];陈建富[1];王海丰[1];胡培君[1,2]

机构：[1]华东理工大学计算化学中心,上海200237;[2]Queen's University of Belfast, Belfast BT9 5AG, UK

年份：2015

卷号：45

期号：12

起止页码：1291

中文期刊名：中国科学：化学

外文期刊名：SCIENTIA SINICA Chimica

收录：CSTPCD;;北大核心:【北大核心2014】；CSCD:【CSCD2015_2016】；PubMed;

基金：国家自然科学基金(21303052,21333003);上海市青年科技启明星计划(14QA1401100);中央高校基本科研业务费专项资金(222201314035)资助

语种：中文

中文关键词：CO2甲烷化;铈锆固溶体;界面催化;协同作用;密度泛函理论

外文关键词：methanation of CO2; ceria-zirconia solid solutions; interfacial catalysis; synergistic effect; density functional theory

摘要：将温室气体CO_2催化加氢转化为CH_4,有利于碳资源化利用和减轻环境污染,是具有一定现实意义的模型化反应.实验发现,氧化物负载型催化剂对CO_2甲烷化过程展现出较高的催化活性和稳定性,但其催化机理和界面作用机制并未得到清楚认识.基于DFT+U计算方法,本文系统研究了复合氧化物Ce_(0.75)Zr_(0.25)O_2负载Ni体系催化CO_2甲烷化复杂基元过程.结果表明,在Ni/Ce_(0.75)Zr_(0.25)O_2(110)体系中,CO_2甲烷化反应涉及CO_2分解和甲酸盐两条途径,且CO_2的分解途径占主导地位,整个反应的控制步骤为CO_2吸附过程.产物甲烷是由界面上CO_2解离加氢产生的CH基团进一步在金属Ni活性位上加氢生成,揭示了该催化体系中载体与负载物之间存在协同催化作用,即载体界面主要发生碳氧化物的脱氧加氢,碳氢中间物种的加氢反应在Ni上发生.
The conversion of the greenhouse gas of CO2 into CH4,which can reduce environmental pollution and make full use of carbon resources,is of fundamental and applied interest.Recently,it was found in experiment that ceria-zirconia solid solutions exhibits high catalytic activity and stability towards CO2 methanation.Herein,by virtue of DFT＋U,we investigate the mechanism of CO2 methanation on the Ni/Ce0.75Zr（0.25）O2 interface.Results show that at the Ni/Ce（0.75）Zr（0.25）O2（110） interface the methanation of CO2 consists of the decomposition of CO2 and formate formation,while the former one plays a dominant role.As for the product,methane originates from the further hydrogenation of CH group on Ni surface,in which CH group is obtained from CO2 decomposition and hydrogenation at the Ni/Ce（0.75）Zr（0.25）O2 interface.Furthermore,we uncover the synergistic effect between support and loaded metal in the system.More specifically,the deoxygenation and hydrogenation of carbonic oxide occur on the Ce（0.75）Zr（0.25）O2（110） surface and the hydrogenation of hydrocarbon proceeds on metallic Ni.