In-situ synthesized Co3O4/Mn3O4 on monolithic nickel foam: Enhanced CO oxidation via MOF-74 derivation

Catalytic combustion has been considered the effective way to oxidize carbon monoxide (CO). It is both crucial and challenging to develop highly-active monolithic catalysts at lower temperatures for industrial applications. This study synthesized a monolithic Co 3 O 4 /Mn 3 O 4 -NF catalyst by the generation of in-situ metal–organic framework (MOF-74)-derived Co 3 O 4 /Mn 3 O 4 on nickel foam (NF). The resulting Co 3 O 4 /Mn 3 O 4 -NF catalyst demonstrated superior low-temperature CO oxidation performance, and the T 90 temperature was 20 °C. The enhanced activity is associated with the increased oxygen vacancy concentration, abundant Co 3+ , Mn 2+  + Mn 3+ , and surface-adsorbed oxygen species (O ads ), as well as low-temperature reducibility. In addition, operando DRIFTS analysis revealed that the surface of this as-prepared catalyst possessed abundant terminal-type oxygen (M O), facilitating CO adsorption and catalytic oxidation. This pioneering study introduces a paradigm-shifting insight: the effectiveness of non-noble metal oxide catalysts can now compete with, and in some cases, outperform their noble metal counterparts. This breakthrough is set to transform the industry, presenting a compelling alternative to conventional noble metal catalysts and propelling the evolution of state-of-the-art environmental conservation technologies.