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How Doping Affects the Activity of the Aluminum Oxide Support |
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| Authors: | Linghui Yan Prof. Dr. Chao Qian Prof. Dr. Shaodong Zhou |
| Affiliation: | 1. College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, 310027 Hangzhou, P. R. China Institute of Zhejiang University – Quzhou, Zheda Rd. #99, 324000 Quzhou, P.R. China;2. College of Chemical and Biological Engineering, Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture Technology, Zhejiang University, 310027 Hangzhou, P. R. China |
| Abstract: | The performance of heteronuclear clusters [AlXO3]+ (X=Al, AlO4, AlMg2O2, AlZnO, AlAu2, Mg, Y, VO, NbO, TaO) in activating methane has been explored by a combination of high–level quantum calculations with reported and supplementary gas-phase experiments. With different dopants in [AlXO3]+, the mechanism, reactivity and selectivity towards methane activation varies accordingly. The classic HAT competes with PCET, depending on the composition of intramolecular interactions. Although the existence of terminal oxygen radical is beneficial for classic HAT, the Alt−C interaction in the [AlXO3]+ clusters as enhanced by the strongly electronegative doping groups (X=Al, AlZnO, Mg, Zn, VO, NbO, TaO) favors the PCET process, facilitating C−H bond breaking. In addition, with different dopants, the destiny of the split methyl group varies accordingly. While strong interaction between Alt and CH3 results in the formation of the Alt−C bond, dopants with variable valance may promote the formation of deep-oxidation products like formaldehyde. It has been discussed in detail how to regulate the activity and selectivity of the active center of the catalyst via rational doping. |
| Keywords: | aluminum oxide doping effects gas-phase reaction methane activation quantum chemical calculation |