Title: | Defective Mn (x)Zr(1- x)O(2) Solid Solution for the Catalytic Oxidation of Toluene: Insights into the Oxygen Vacancy Contribution |
Author(s): | Yang X; Yu X; Jing M; Song W; Liu J; Ge M; |
Address: | "State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), CAS Research/Education Center for Excellence in Molecular Sciences , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , P. R. China. University of Chinese Academy of Sciences , Beijing 100049 , P. R. China. State Key Laboratory of Heavy Oil Processing, College of Science , China University of Petroleum-Beijing , Beijing 102249 , P. R. China. Center for Excellence in Regional Atmospheric Environment , Institute of Urban Environment, Chinese Academy of Sciences , Xiamen 361021 , P. R. China" |
Journal Title: | ACS Appl Mater Interfaces |
ISSN/ISBN: | 1944-8252 (Electronic) 1944-8244 (Linking) |
Abstract: | "Oxygen vacancy is conducive to molecular oxygen adsorption and activation, and it is necessary to estimate its contribution on catalysts, especially the doped system for volatile organic compound (VOC) oxidation. Herein, a series of doped Mn (x)Zr(1- x)O(2) catalysts with oxygen vacancy were prepared by partially substituting Zr(4+) in a zirconia with low-valent manganese (Mn(2+)). Compared with the corresponding mechanically mixed samples (MB-x) without oxygen vacancy, Mn (x)Zr(1- x)O(2) catalysts exhibited better toluene conversion and specific reaction rate, where the differential values were calculated to estimate the contribution of oxygen vacancy on catalytic performance. The increase in oxygen vacancy concentrations in Mn (x)Zr(1- x)O(2) catalysts can boost the differential values, implying the enhancement of oxygen vacancy contribution. Density functional theory (DFT) calculations further confirmed the contribution of oxygen vacancy, and molecular oxygen is strongly absorbed and activated on a defective Mn-doped c-ZrO(2) (111) surface with oxygen vacancy rather than a perfect m-ZrO(2) (-111) surface or a perfect Mn-doped c-ZrO(2) (111) surface, thus resulting in the significant improvement in catalytic activity for toluene oxidation. In situ DRIFTS spectra revealed that the oxygen vacancy can alter the toluene degradation pathway and accelerate the intermediates to convert into CO(2) and H(2)O, thus leading to a low activation energy and high specific reaction rate" |
Keywords: | DFT calculations MnxZr1-xO2 solid solution molecular oxygen activation oxygen vacancy contribution toluene oxidation; |
Notes: | "PubMed-not-MEDLINEYang, Xueqin Yu, Xiaolin Jing, Meizan Song, Weiyu Liu, Jian Ge, Maofa eng 2018/12/14 ACS Appl Mater Interfaces. 2019 Jan 9; 11(1):730-739. doi: 10.1021/acsami.8b17062. Epub 2018 Dec 19" |