Insight into the boosted catalytic performance and chlorine resistance of nanosphere-like meso-macroporous CrO_x/MnCo₃O_x for 1,2-dichloroethane destruction

Catalyst chlorine poisoning is a critical issue to be solved for chlorine-containing VOCs decomposition. Herein, we found that three-dimensional nanosphere-like meso-macroporous MnCo₃O_x (SMC-F) synthesized via a co-precipitation method has much higher activity and selectivity for 1,2-dichloroethane destruction than the bulk MnCo₃O_x; however, polychlorinated by-products as 1,1,2-trichloroethane, trichloroethylene, perchloroethylene, trichloromethane and perchloromethane originated from the cleavage of C–Cl and C–C bonds can be detected. As such, CrO_x was further introduced to enhance the low temperature activity and selectivity of SMC-F. Results reveal that the incorporation of CrO_x boosts surface lattice oxygen (O²⁻) amount and mobility and generates highly reducible Cr⁶⁺ and Mn⁴⁺ species in Cr/SMC-F, improving its activity and selectivity remarkably. Only 1,1,2-trichloroethane can be found during 1,2-dichloroethane destruction as the C–C bond cleavage route is generally inhibited over Cr/SMC-F. The improved O²⁻ mobility and oxidation property of Cr/SMC-F facilitate surface Cl desorption, ensuring its superior catalytic efficiency and chlorine resistance.