Unraveling specific role of carbon matrix over Pd/Quasi-Ce-MOF facilitating toluene enhanced degradation

Abstract MOFs (Metal organic frameworks) derivatives represented by quasi-MOFs have excellent physical and chemical properties and can be applied for the catalytic combustion of VOCs. In this work, Pd/quasi-Ce-BTC synthesized by simple one-step N2 pyrolysis was applied to the oxidation of toluene, showing excellent toluene catalytic activity (T90=175 °C, 30000 mL/(g·h)). Microscopic analyses indicate the formation and interaction of a carbon matrix composite quasi-MOF structure interface. The results show that the amorphous carbon matrix formed during the partial pyrolysis of Ce-BTC significantly improves the adsorption and activation capacity of toluene in the reaction, and constructes a reductive system to maintain high concentrations of Ce3+ and Pd0, which can facilitate the activation and utilization of oxygen in reaction. Quasi in-situ XPS proves that carbon matrix is indirectly involved in the activation and storage of oxygen, and Pd0 is the crucial active site for the activation of oxygen. Stability and water resistance tests display good stability of Pd/quasi-Ce-BTC. This work provides a potential method for designing quasi-MOF catalysts towards VOCs effective abatement.