催化学报

催化学报 ›› 2020, Vol. 41 ›› Issue (2): 286-293.DOI: 10.1016/S1872-2067(19)63445-5

• 论文 • 上一篇    下一篇

光照对Pt/Al2O3光热CO2加氢反应的增强作用

赵梓俨a,b, Dmitry E. Doronkinc, 叶英浩b, Jan-Dierk Grunwaldtc,d, 黄泽皑a,b, 周莹a,b   

  1. a 西南石油大学油气藏地质及开发工程国家重点实验室, 四川成都 610500, 中国;
    b 西南石油大学材料科学与工程学院新能源材料及技术研究中心, 四川成都 610500, 中国;
    c 卡尔斯鲁厄理工学院化学技术与高分子化学研究所, 卡尔斯鲁厄 76131, 德国;
    d 卡尔斯鲁厄理工学院催化研究与技术研究所, 卡尔斯鲁厄 76344, 德国
  • 收稿日期:2019-05-14 修回日期:2019-07-05 出版日期:2020-02-18 发布日期:2019-11-04
  • 通讯作者: 周莹, Dmitry E. Doronkin
  • 基金资助:
    国家自然科学基金（U1862111，U1232119）；四川省国际合作项目（2017HH3030）；四川省创新团队（2016TD00 11）.

Visible light-enhanced photothermal CO2 hydrogenation over Pt/Al2O3 catalyst

Ziyan Zhaoa,b, Dmitry E. Doronkinc, Yinghao Yeb, Jan-Dierk Grunwaldtc,d, Zeai Huanga,b, Ying Zhoua,b   

  1. a State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, Sichuan, China;
    b The Center of New Energy Materials and Technology, School of Materials Science and Engineering, Southwest Petroleum University, Chengdu 610500, Sichuan, China;
    c Institute for Chemical Technology and Polymer Chemistry (ITCP), Karlsruhe Institute of Technology, Karlsruhe (KIT), 76131 Karlsruhe, Germany;
    d Institute of Catalysis Research and Technology (IKFT), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen, Germany
  • Received:2019-05-14 Revised:2019-07-05 Online:2020-02-18 Published:2019-11-04
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (U1862111, U1232119), Sichuan Provincial International Cooperation Project (2017HH0030), the Innovative Research Team of Sichuan Province (2016TD0011).

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摘要： 在传统热催化材料的研究领域中，光照技术已经得到了广泛的应用，从而使传统热催化剂的催化反应活性和选择性得到优化.然而，在光热协同催化反应过程中，光照因素对催化反应过程的影响尚未得到很好地研究和理解.本文通过浸渍法制得Pt/Al2O3催化剂，并应用于光热协同催化CO2加氢反应.结果证明，在光热协同CO2加氢催化反应中，Pt/Al2O3催化剂表现出光热协同效应.本文结合原位漫反射红外光谱（operando DRIFTS）和密度泛函理论计算（DFT）对光照因素对该催化反应过程的作用机制进行了进一步深入研究.结果表明，CO气体分子从Pt纳米颗粒上的脱附过程为CO2加氢反应的重要步骤； CO气体分子在Pt纳米颗粒上脱附的位置包含台阶位置（Ptstep）和平台位置（Ptterrace）.结果表明，反应过程中CO气体分子从Pt表面的脱附有利于催化剂暴露出Pt反应活性位点.值得注意的是，在光热协同催化CO2加氢反应过程中，光照和温度因素对CO气体分子的脱附过程具有不同影响.吸附能的计算结果证明，CO气体分子吸附在Ptstep和Ptterrace上的吸附能分别为-1.24和-1.43eV.由此可见，CO气体分子与Pt纳米颗粒上的Ptstep吸附位点之间相互作用更强.在无光照作用的条件下对催化剂进行加热，CO气体分子更容易从Ptterrace吸附位点发生脱附；但是在对应的温度下加入光照作用后，吸附在Ptstep位点上的CO气体分子会先转移到Ptterrace吸附位点上，随后脱附，从而促进CO2加氢反应的进行.

关键词: 二氧化碳加氢, 光热催化, 铂/三氧化二铝, 原位漫反射红外光谱, 密度泛函理论

Abstract: Light illumination has been widely used to promote activity and selectivity of traditional thermal catalysts. Nevertheless, the role of light irradiation during catalytic reactions is not well understood. In this work, Pt/Al2O3 prepared by wet impregnation was used for photothermal CO2 hydrogenation, and it showed a photothermal effect. Hence, operando diffuse reflectance infrared Fourier-transform spectroscopy and density functional theory calculations were conducted on Pt/Al2O3 to gain insights into the reaction mechanism. The results indicated that CO desorption from Pt sites including step sites (Ptstep) or/and terrace site (Ptterrace) is an important step during CO2 hydrogenation to free the active Pt sites. Notably, visible light illumination and temperature affected the CO desorption in different ways. The calculated adsorption energy of CO on Ptstep and Ptterrace sites was -1.24 and -1.43 eV, respectively. Hence, CO is more strongly bound to the Ptstep sites. During heating in the dark, CO preferentially desorbs from the Ptterrace site. However, the additional light irradiation facilitates transfer of CO from the Ptstep to Ptterrace sites and its subsequent desorption from the Ptterrace sites, thus promoting the CO2 hydrogenation.

Key words: CO2 hydrogenation, Photothermal catalysis, Pt/Al2O3 Operando diffuse reflectance infrared, Fourier transform spectroscopy, Density functional theory