作者:Saifei Wang,Jie Liu,Yiyuan Zhang,Peiqi Chu,Haobin Liu,Man Wang,Erhong Duan
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 LaCoO3@MgO-0.1.The 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.
发文机构:School of Environmental Science and Engineering
关键词:PerovskiteoxidesCore-shellstructureSurfaceacid-basepropertiesMethanecatalyticoxidationRareearths
分类号: X752[环境科学与工程—环境工程]O643.36[理学—物理化学]