Constructing Co₂Al₁Mo_xO catalysts by Mo₇O₂₄^6- intercalated CoAl-LDHs for boosting the catalytic oxidation for C₃H₈...

Series of Co₂Al₁Mo_xO catalysts derived from Mo₇O₂₄^6- intercalated CoAl-LDHs precursor were synthesized and evaluated for C₃H₈ and CO oxidation. Moderate Mo introduction enhanced the Co³⁺ and oxygen vacancies concentration on Co₂Al₁Mo_xO surface, which were more conducive to C₃H₈ and CO oxidation, respectively. Co₂Al₁Mo_0.5O exhibited the highest catalytic performance in both single and binary gas oxidation reactions, with the TOF values of 2.3 × 10^-4 s^-1 (C₃H₈) and 3.21 × 10^-3 s^-1 (CO). In-situ XPS and TPD/TPSR techniques revealed that C₃H₈ oxidation on Co₂Al₁Mo_xO surface followed MvK mechanism and CO oxidation followed MvK and E-R mechanism. Notably, Co₂Al₁Mo_0.5O catalyst effectively mitigated the mutual inhibition between C₃H₈ and CO co-oxidation, mainly due to its ability to provide more active sites for intermediates transformation. This work advances the understanding of mixed gas oxidation and highlights the critical role of Co³⁺ and oxygen vacancies during C₃H₈ and CO co-oxidation, representing a significant step for practical VOCs oxidation.