Oxidative decomposition of chlorobenzene on MnaVOX catalysts: The critical roles of oxygen vacancies and hollow structure

It is urgent to build a catalyst with high activity and stability to remove chlorinated volatile organic compounds (CVOCs) efficiently due to their strong toxicity. Here, three-dimensional (3D) petal spherical with hierarchical hollow porous structures were synthesized by a facile wet-chemical self-assembly and a low-temperature calcination strategy. Benefiting from the oxygen vacancy defects varies and 3D structures under a certain amount of Mn content, thereby the as-obtained MnaVOX catalysts could regulate the number of active sites and the final catalytic performance. As expected, it shows that the conversion temperature (T90) of oxidation of chlorobenzene (CB) with the optimized free-standing catalyst (Mn1.2VOX) is 229 °C, with low activity energy (30.5 KJ/mol). Moreover, the degradation efficiency of the catalyst for CB remained above 99% after continuous testing at 300 °C for 60 h. This work provides a new strategy for exploring a substitute advanced catalysts for noble metals with controllable vacancy defects and desired nano/micro structures to facilitate the catalytic oxidation reaction in CVOCs.