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The defect plays a significant role in tuning the electronic structure of metal compounds such as oxides, chlorides, sulfides and nitrides, which is frequently used to explain the enhanced catalytic activity. However, the dynamic change of defect relating to the oxidation state change during the reaction is rarely addressed, and it is still not able to be appropriately predicted since the kinetic modeling of the redox reaction involving the in‐situ formation of defects is challenged by the dynamic evolution of the active sites and the complex kinetic phenomena. Here, for the first time, we present a general method to build a new kinetic model of the redox reaction cycle by combined kinetics of reduction‐ and oxidation steps to predict the time and spatially resolved formation of defects of solid catalysts and the reaction products in ethylene oxychlorination on CuCl2/Al2O3 catalyst. The defect concentration can be tuned by manipulating the relative rates of the reduction‐ and oxidation steps. [ABSTRACT FROM AUTHOR]

A ZnO-nanolayer-coated carbon nanotube (CNT) composite (ZnO-CNT) was employed as a support to immobilise Ni catalysts. Well-mixed oxides, formed as a result of enhanced interfaces between the two oxides on CNTs, resulted in the formation of Ni-Zn alloys in reduced catalysts. The Ni/ZnO-CNT catalyst exhibited much higher yields of vicinal diols, for example, ethylene glycol and 1,2-propylene glycol, from the conversion of cellulose than the reference Ni/CNT catalyst. A plausible reaction network on the Ni/ZnO-CNT catalyst has been proposed. Moreover, the effects of Ni loading and catalyst reduction temperature on the catalytic performance were probed, and the relationship between the catalyst structure and the yields of vicinal diols was correlated. The Ni-rich alloy, relative to the Zn-rich alloy, was suggested as the dominating active phase for the selective conversion of cellulose into vicinal diols. This might shed new light on the design and optimisation of Ni-based catalysts for the catalytic conversion of cellulose with the Ni-Zn interaction. [ABSTRACT FROM AUTHOR]