| Title: | Improved and Reduced Performance of Cu- and Ni-Substituted Co(3)O(4) Catalysts with Varying Co(Oh)/Co(Td) and Co(3+)/Co(2+) Ratios for the Complete Catalytic Oxidation of VOCs |
| Author(s): | Ma Y; Wang L; Ma J; Liu F; Einaga H; He H; |
| Address: | "State Key Joint Laboratory of Environment Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. University of Chinese Academy of Sciences, Beijing 100049, China. Center for Excellence in Regional Atmospheric Environment, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Department of Civil, Environmental, and Construction Engineering (CECE), Catalysis Cluster for Renewable Energy and Chemical Transformations (REACT), NanoScience Technology Center (NSTC), University of Central Florida, Orlando, Florida 32816, United States. Faculty of Engineering Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
| Abstract: | "The Co(3)O(4) spinel is one of the most promising transition metal oxide (TMO) catalysts for volatile organic compound (VOC) treatment. Substituting effects have usually been utilized to improve the catalytic performance of the Co(3)O(4) spinel. In this study, Cu- and Ni-substituted Co(3)O(4) catalysts derived from mixed metal-organic frameworks (MMOFs) retained similar spinel structures but exhibited improved and reduced performance for o-xylene oxidation, respectively. Physicochemical characterization and DFT calculations revealed that Cu and Ni substitution into the Co(3)O(4) spinel varied the valence (Co(3+)/Co(2+)) and geometry (Co(Oh)/Co(Td)) distributions of Co cations through different partial electron transfer and substitution sites. The higher Co(3+)/Co(2+) and Co(Oh)/Co(Td) ratios of the CuCo(2)O(4) catalyst contributed to the superior reducibility and oxygen mobility, which facilitated the oxidation of intermediates at lower temperatures in the catalytic oxidation of o-xylene. Meanwhile, the NiCo(2)O(4) catalyst with lower Co(3+)/Co(2+) and Co(Oh)/Co(Td) ratios could not completely oxidize intermediates under the same conditions due to inferior redox properties. Therefore, the CuCo(2)O(4) catalyst showed superior catalytic activity and stability to the NiCo(2)O(4) catalyst for the catalytic oxidation of o-xylene. This work provides insights into the synthesis of substituted Co(3)O(4) catalysts from MMOFs and mechanism of substituting effects, which might guide the design of efficient TMO catalysts for VOC treatment" |
| Keywords: | Co3+/Co2 + Co3O4 spinel CoOh/CoTd MMOFs VOCs substituting effects; |
| Notes: | "PubMed-not-MEDLINEMa, Ying Wang, Lian Ma, Jinzhu Liu, Fudong Einaga, Hisahiro He, Hong eng 2022/06/23 Environ Sci Technol. 2022 Jul 5; 56(13):9751-9761. doi: 10.1021/acs.est.2c02450. Epub 2022 Jun 22" |
