Local Electron Environment Regulation of Spinel CoMn 2 O 4 Induced Effective Reactant Adsorption and Transformation of Lattice Oxygen for Toluene Oxidation

作者：Cui Dong, Chenyu Yang, Yewei Ren, Hongchun Sun, Hui Wang, Jianping Xiao, Zhenping Qu · 发表于：Environmental Science & Technology · 年份：2023 · DOI：10.1021/acs.est.3c06782 · 被引用次数：60 · 研究领域：Catalytic Processes in Materials Science、Catalysis and Oxidation Reactions、Electrocatalysts for Energy Conversion

In contrast to numerous studies on oxygen species, the interaction of volatile organic compounds (VOCs) with oxides is also critical to the catalytic reaction but has hardly been considered. Herein, we develop a highly efficient Pt atom doped spinel CoMn 2 O 4 (Pt-CoMn) for oxidation of toluene at low temperature, and the toluene conversion rate increased by 18.3 times (129.7 versus 7.1 × 10 –11 mol/(m 2 ·s)) at 160 °C compared to that of CoMn 2 O 4 . Detailed characterizations and density functional theory calculations reveal that the local electron environment of the Co sites is changed after Pt doping, and the formed electron-deficient Co sites in turn strengthen the interaction with toluene. Adsorbed toluene will react with lattice oxygen in Pt-CoMn and CoMn catalysts and convert into benzoate intermediates, and the consumption rate of benzoate is closely related to the activation of gaseous oxygen. Significantly, the abundant bulk defects of Pt-CoMn help to open the reaction channel in the CoMn spinel, which acts as an oxygen pump to promote the transformation of bulk lattice oxygen into surface lattice oxygen at lower temperatures, thus accelerating the conversion rate of benzoate intermediates into CO 2 and enhancing low-temperature combustion of toluene. Pt-CoMn developed here emphasizes the regulation of VOCs adsorption strength and lattice oxygen transformation processes on CoMn 2 O 4 by adjusting the local electron environment, which will provide new guidance for t...