Yolk-shell-like mesoporous CoCrOx with superior activity and chlorine resistance in dichloromethane destruction

Abstract Promoting chlorine resistance and inhibiting by-product generation are critical issues in catalytic destruction of chlorinated volatile organic compounds (CVOCs). Herein, a yolk-shell-like mesoporous CoCrOx as a robust catalyst was synthesized for deep destruction of dichloromethane (DCM) considering its superior mass transfer and molecule enrichment ability. The strong interaction between Co and Cr elements in CoCrOx results in efficient generation of active Cr6+ and oxygen species, which greatly enhances the activity of CoCrOx in DCM oxidation, much higher than that of Co3O4, Co3O4+Cr2O3 and Cr2O3. Chloromethane (CH3Cl), trichloromethane (CHCl3) and tetrachloromethane (CCl4) can be detected as the cleavage of C H bond and generation of C-Cl bond during DCM destruction. We found that the acid sites can effectively inhibit the formation of by-products over CoCrOx material, which is a promising material for CVOC elimination. The results from this work provide some new insights into the design of catalysts for CVOC destruction.