Multiple interface coupling in ultrathin Mn-based composites for superior catalytic oxidation: Implications of interface coupling on structural defects

Manganese oxide has been recognized as one of the most promising gaseous heterogeneous catalysts due to its low cost, environmental friendliness , and high catalytic oxidation performance. The modulation of the interfacial coupling effect of manganese oxides by chemical means is considered a critical and effective way to improve the catalytic performance. Herein, a novel one-step synthetic strategy of highly-efficient ultrathin manganese-based catalysts is proposed through optimal regulation of metal/manganese oxide multi-interfacial coupling. Carbon monoxide (CO) and propane (C 3 H 8 ) oxidation are employed as probe reactions to investigate the structure-catalytic mechanism - catalytic performance relationship. The ultrathin manganese (Mn)-based catalyst exhibits superior low-temperature catalytic activity with a 90% conversion of CO/C 3 H 8 realized at 106℃ and 350℃. Subsequently, the effect of “interfacial effect” on the intrinsic properties of manganese oxides is revealed. The ultrathin appearance of two–dimensional (2D) manganese dioxide (MnO 2 ) nanosheets changes the binding force in the vertical direction, thus resulting in an increase in the average manganese-oxygen (Mn-O) bond length and exposing more surface defects . Besides, the introduction of Copper (Cu) species into the catalyst further weakens the Mn-O bond and promotes the generation of oxygen vacancies , which subsequently enhances the oxygen migration rate. This study provides new insights into the optimal design of transition metal oxide interfacial assemblies for efficient catalytic reactions .