| Title: | Acid Etching-Induced In Situ Growth of lambda-MnO(2) over CoMn Spinel for Low-Temperature Volatile Organic Compound Oxidation |
| Author(s): | Shan C; Zhang Y; Zhao Q; Fu K; Zheng Y; Han R; Liu C; Ji N; Wang W; Liu Q; |
| Address: | "Department of Environmental Science and Technology, Tianjin Key Lab of Indoor Air Environmental Quality Control, State Key Laboratory of Engines, Tianjin University, Tianjin 300350, China. State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Department of Electronics, National Institute for Advanced Materials, Renewable Energy Conversion and Storage Center, Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology, Nankai University, Tianjin 300071, China" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "Surface lattice oxygen is crucial to the degradation of volatile organic compounds (VOCs) over transition metal oxides according to the Mars-van Krevelen mechanism. Herein, lambda-MnO(2) in situ grown on the surface of CoMn spinel was prepared by acid etching of corresponding spinel catalysts (CoMn-Hx-Ty) for VOC oxidation. Experimental and relevant theoretical exploration revealed that acid etching on the CoMn spinel surface could decrease the electron cloud density around the O atom and weaken the adjacent Mn-O bond due to the fracture of the surface Co-O bond, facilitating electron transfer and subsequently the activation of surface lattice oxygen. The obtained CoMn-H1-T1 exhibited an excellent catalytic performance with a 90% acetone conversion at 149 degrees C, which is 42 degrees C lower than that of CoMn spinel. Furthermore, the partially maintained spinel structure led to better stability than pure lambda-MnO(2). In situ diffuse reflectance infrared Fourier transform spectroscopy confirmed a possible degradation pathway where adsorptive acetone converted into formate and acetate species and into CO(2), in which the consumption of acetate was identified as the rate-limiting step. This strategy can improve the catalytic performance of metal oxides by activating surface lattice oxygen, to broaden their application in VOC oxidation" |
| Keywords: | MvK mechanism VOC oxidation acid etching spinel surface lattice oxygen lambda-MnO2; |
| Notes: | "PubMed-not-MEDLINEShan, Cangpeng Zhang, Yan Zhao, Qian Fu, Kaixuan Zheng, Yanfei Han, Rui Liu, Caixia Ji, Na Wang, Weichao Liu, Qingling eng 2022/06/17 Environ Sci Technol. 2022 Jul 19; 56(14):10381-10390. doi: 10.1021/acs.est.2c02483. Epub 2022 Jun 16" |
