Title: | Thermal Annealing Induced Surface Oxygen Vacancy Clusters in alpha-MnO(2) Nanowires for Catalytic Ozonation of VOCs at Ambient Temperature |
Author(s): | Lu Y; Deng H; Pan T; Zhang C; He H; |
Address: | "Center for Excellence in Regional Atmospheric Environment, Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. University of Chinese Academy of Sciences, Beijing 100049, China. Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China" |
Journal Title: | ACS Appl Mater Interfaces |
ISSN/ISBN: | 1944-8252 (Electronic) 1944-8244 (Linking) |
Abstract: | "Catalytic ozonation has gained considerable interest in volatile organic compound (VOC) elimination due to its mild reaction conditions. However, the low activity and mineralization rate of VOCs over catalysts hinder its practical application. Herein, a series of alpha-MnO(2) nanowire catalysts were prepared via thermal annealing treatment at various temperatures to tailor defect species. Numerous characterization techniques were used and combined to investigate the relationship between activity and microstructure. PALS and XAFS indicated that more unsaturated manganese and oxygen vacancies, especially surface oxygen vacancy clusters, were produced in alpha-MnO(2) under the optimal high calcination temperature. As a result, MnO(2)-600 was found to exhibit the best-ever performance in toluene conversion (95%) and mineralization rate (89.5%) at 20 degrees C, making it a promising candidate for practical use. The roles of these defects in manipulating the reactive oxygen species of alpha-MnO(2) were clarified by quantifying the amounts of reactive oxygen species by quenching experiments and density functional theory calculations. (1)O(2) and .OH species generated in the vicinity of oxygen vacancy clusters, especially the dimer oxygen vacancy cluster, were identified as key oxygen species in the abatement of toluene. This study provides a facile method to engineer the microstructure of MnO(2) by means of the manipulation of oxygen vacancies and an in-depth understanding of their roles in the catalytic ozonation of VOC" |
Keywords: | catalytic ozonation density functional theory manganese oxides reactive oxygen species surface oxygen vacancy clusters; |
Notes: | "PublisherLu, Yuqin Deng, Hua Pan, Tingting Zhang, Changbin He, Hong eng 2023/02/09 ACS Appl Mater Interfaces. 2023 Feb 8. doi: 10.1021/acsami.2c21120" |