Pseudo core-shell LaCoO3@MgO perovskite oxides for high performance methane catalytic oxidation  

作　　者：Saifei Wang Jie Liu Yiyuan Zhang Peiqi Chu Haobin Liu Man Wang Erhong Duan 

机构地区：[1]School of Environmental Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,China

出　　处：《Journal of Rare Earths》2021年第1期51-57,I0002,共8页稀土学报（英文版）

基　　金：Project supported by the Ministry of Education Blue Fire Program(XZJH201717)。

摘　　要：Magnesia modified LaCoO3 was prepared by a facile one-step sol-gel method and used for removal of dilute methane.Compared with the conventional doping technique,the obtained LaCoO3@MgO-x exhibits pseudo core-shell structure and shows superior catalytic activity.The methane conversion exceeds90%at 532℃on LaCoO3@MgO-0.1,while only 60%of methane is conversed using the doped perovskite LaCo0.9Mg0.1O3.The high catalytic performance of LaCoO3@MgO-0.1 is mainly attributed to the adjustment of surface acid-base properties by the MgO shell structure.According to density functional theory(DFT)calculation,the methane is more likely to be adsorbed and cracked on [e-mail] in situ DRIFTS shows that CH3-O-CH3 intermediate specie is formed.The pseudo core-shell structure also enhances the stability and the LaCoO3@MgO-0.1 maintains high activity after working for 100 h.The above results demonstrate that surface modification by magnesia is an effective strategy for improving LaCoO3 catalytic performance.

关 键 词：Perovskite oxides Core-shell structure Surface acid-base properties Methane catalytic oxidation Rare earths 

分 类 号：X752[环境科学与工程—环境工程] O643.36[理学—物理化学]