Electronic coupling in bifunctional Pd–CoO_x interfaces drives reactive oxygen activation for acetone low-temperature oxidation

Integrating transition-metal oxides into noble-metal catalysts has proven effective in enhancing catalytic performance. However, oxygenated volatile organic compounds (OVOCs) purification over bimetallic catalysts is still limited by weak coupling and the accumulation of reaction intermediates. Strengthening the interaction in bimetallic sites offers a promising strategy to overcome these limitations, as it can modulate the electronic structure and d-band center of noble-metal species, thereby promoting the activation of OVOCs and ensuring the desired reaction pathways. Herein, bifunctional Pd–CoO_x sites were stabilized on rod-like SBA-15, where electronic coupling between Pd²⁺ and Co²⁺ enables efficient charge redistribution and promotes molecular oxygen activated to highly reactive oxygen (O⁻). This interfacial synergy directs acetone oxidation via a kinetically favorable pathway of acetone, aldehydes to carboxylates, while promoting rapid decomposition of key intermediates such as CH₂O* and C₂H₄O₂, and avoids the formation of C₂H₂O intermediate. Meanwhile, this oxygen-mediated pathway remains operative under complex reaction atmospheres (H₂S and CH₃Cl), accounting for the exceptional catalytic stability of PdCoO_x/SBA-15. This work offers valuable insights on the development of specific catalysts with functional active sites to synergistically enhance reactants and surface oxygen species activation for efficient OVOCs oxidation.