“面向碳中和的CO2捕集转化前沿进展”专刊文章（一）｜还原预处理对二氧化碳加氢制甲醇Ir-In2O3催化剂结构和催化性能的影响

Effect of reduction pretreatment on the structure and catalytic performance of Ir-In₂O₃ catalysts for CO₂ hydrogenation to methanol

Changyu Ding, Feifei Yang, Xue Ye, Chongya Yang, Xiaoyan Liu, Yuanlong Tan, Zheng Shen, Hongmin Duan, Xiong Su^*, Yanqiang Huang*

https://doi.org/10.1016/j.jes.2023.01.018

In₂O₃催化剂在二氧化碳加氢制甲醇过程中很有应用前景。氧空位被认为是该反应的活性中心，然而理解In₂O₃中氧物种的状态与催化性能的关联仍然是个挑战。我们比较了不同Ir负载量和不同还原温度预处理的In₂O₃和Ir-In₂O₃催化剂的性质。相比In₂O₃，Ir-In₂O₃上的二氧化碳转化速率有所提升。通过加入很少量的Ir，In₂O₃上高度分散的Ir物种增加了氧空位浓度，由此提高了活性。通过精细调控催化剂结构， 300°C预还原Ir负载量为0.16 wt.%的催化剂有最高的甲醇收率（146 mgCH₃OH/(g_cat·hr)）。Raman、EPR、XPS、二氧化碳程序升温脱附和脉冲吸附等多种催化剂表征手段证实较高还原温度会产生较多的氧空位，使得二氧化碳吸附和脱附循环变得更容易。为了获得具有更高性能的二氧化碳制甲醇催化剂，需要使得In₂O₃表面氧原子和氧空位达到很好的动态平衡。

In₂O₃ has been found a promising application in CO₂ hydrogenation to methanol, which is beneficial to the utilization of CO₂. The oxygen vacancy (O_v) site is identified as the catalytic active center of this reaction. However, there remains a great challenge to understand the relations between the state of oxygen species in In₂O₃ and the catalytic performance for CO₂ hydrogenation to methanol. In the present work, we compare the properties of multiple In₂O₃ and Ir-promoted In₂O₃ (Ir-In₂O₃) catalysts with different Ir loadings and after being pretreated under different reduction temperatures. The CO₂ conversion rate of Ir-In₂O₃ is more promoted than that of pure In₂O₃. With only a small amount of Ir loading, the highly dispersed Ir species on In₂O₃ increase the concentration of Ov sites and enhance the activity. By finely tuning the catalyst structure, Ir-In₂O₃ with an Ir loading of 0.16 wt.% and pre-reduction treatment under 300°C exhibits the highest methanol yield of 146 mgCH₃OH/(g_cat·hr). Characterizations of Raman, electron paramagnetic resonance, X-ray photoelectron spectroscopy, CO₂-temperature programmed desorption and CO₂-pulse adsorption for the catalysts confirm that more Ov sites can be generated under higher reduction temperature, which will induce a facile CO₂ adsorption and desorption cycle. Higher performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies, which guides us to find more suitable conditions for catalyst pretreatment and reaction.

通讯作者

苏雄，1984年出生于湖北省恩施市。2007年7月于大连理工大学获得化学工程与工艺和英语专业双学位；2013年博士毕业于中国科学院大连化学物理研究所工业催化专业，师从刘中民研究员，毕业后留所工作。目前主要从事无机多孔材料CO₂吸附剂及CO₂催化转化利用催化剂的研究工作。

黄延强，1980年出生于山东省济南市，2002年毕业于大连理工大学(学士)，2008年于中国科学院大连化学物理研究所获博士学位(工业催化)。毕业后留所工作至今，曾赴西班牙卡迪斯大学、美国哥伦比亚大学短期进修。在Nature Energy, JACS, Angew等国内外权威刊物上发表论文100余篇，受邀为Chem. Soc. Rev., Acc. Chem. Res.等刊物撰写综述，申请发明专利50余件(授权20件)。2019年获得国家杰出青年基金资助。现任《Journal of Energy Chemistry》副主编，《Chinese Journal of Catalysis》等刊物青年编委。先后入选中国科学院青年创新促进会会员、辽宁省百千万人才工程（万人层次）、兴辽英才计划等荣誉称号。现承担科技部、基金委以及其他部委多项课题。

https://www.sciencedirect.com/science/article/pii/S1001074223000219

Changyu Ding, Feifei Yang, Xue Ye, Chongya Yang, Xiaoyan Liu, Yuanlong Tan, Zheng Shen, Hongmin Duan, Xiong Su, Yanqiang Huang, 2024. Effect of reduction pretreatment on the structure and catalytic performance of Ir-In₂O₃ catalysts for CO₂ hydrogenation to methanol. J. Environ. Sci. 140, 2-11.