| Title: | Comparative Study of alpha- and beta-MnO(2) on Methyl Mercaptan Decomposition: The Role of Oxygen Vacancies |
| Author(s): | Su H; Liu J; Hu Y; Ai T; Gong C; Lu J; Luo Y; |
| Address: | "Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China. The Innovation Team for Volatile Organic Compounds Pollutants Control and Resource Utilization of Yunnan Province, The Higher Educational Key Laboratory for Odorous Volatile Organic Compounds Pollutants Control of Yunnan Province, Kunming 650500, China. Faculty of Chemical Engineering, Kunming University of Science and Technology, Kunming 650500, China" |
| ISSN/ISBN: | 2079-4991 (Print) 2079-4991 (Electronic) 2079-4991 (Linking) |
| Abstract: | "As a representative sulfur-containing volatile organic compounds (S-VOCs), CH(3)SH has attracted widespread attention due to its adverse environmental and health risks. The performance of Mn-based catalysts and the effect of their crystal structure on the CH(3)SH catalytic reaction have yet to be systematically investigated. In this paper, two different crystalline phases of tunneled MnO(2) (alpha-MnO(2) and beta-MnO(2)) with the similar nanorod morphology were used to remove CH(3)SH, and their physicochemical properties were comprehensively studied using high-resolution transmission electron microscope (HRTEM) and electron paramagnetic resonance (EPR), H(2)-TPR, O(2)-TPD, Raman, and X-ray photoelectron spectroscopy (XPS) analysis. For the first time, we report that the specific reaction rate for alpha-MnO(2) (0.029 mol g(-1) h(-1)) was approximately 4.1 times higher than that of beta-MnO(2) (0.007 mol g(-1) h(-1)). The as-synthesized alpha-MnO(2) exhibited higher CH(3)SH catalytic activity towards CH(3)SH than that of beta-MnO(2), which can be ascribed to the additional oxygen vacancies, stronger surface oxygen migration ability, and better redox properties from alpha-MnO(2). The oxygen vacancies on the catalyst surface provided the main active sites for the chemisorption of CH(3)SH, and the subsequent electron transfer led to the decomposition of CH(3)SH. The lattice oxygen on catalysts could be released during the reaction and thus participated in the further oxidation of sulfur-containing species. CH(3)SSCH(3), S(0), SO(3)(2-), and SO(4)(2-) were identified as the main products of CH(3)SH conversion. This work offers a new understanding of the interface interaction mechanism between Mn-based catalysts and S-VOCs" |
| Keywords: | CH3SH decomposition MnO2 oxygen migration oxygen vacancies; |
| Notes: | "PubMed-not-MEDLINESu, Hong Liu, Jiangping Hu, Yanan Ai, Tianhao Gong, Chenhao Lu, Jichang Luo, Yongming eng 42207127, 42030712, 21966018/National Natural Science Foundation of China/ 202101AS070026/Key Project of Natural Science Foundation of Yunnan Province/ 202101BE070001-027, 2022J0069, 202105AE160019/Applied Basic Research Foundation of Yunnan Province/ Switzerland 2023/02/26 Nanomaterials (Basel). 2023 Feb 19; 13(4):775. doi: 10.3390/nano13040775" |
