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 effec-tive 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/man-ganese oxide multi-interfacial coupling. Carbon monoxide (CO) and propane (C3H8) 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/C3H8 realized at 106celcius and 350celcius. Subsequently, the effect of inter-facial effect on the intrinsic properties of manganese oxides is revealed. The ultrathin appearance of two-dimensional (2D) manganese dioxide (MnO2) 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.(c) 2023 Elsevier Inc. All rights reserved.

Automated summary

Manganese oxide is a promising gaseous heterogeneous catalyst with low cost, environmental friendliness, and high catalytic oxidation performance. Modulating the interfacial coupling effect of manganese oxides through chemical means is an effective way to improve their catalytic performance. This study proposes a novel one-step synthetic strategy for highly efficient ultrathin manganese-based catalysts by optimizing metal/manganese oxide multi-interfacial coupling. The study also reveals the effect of interfacial effect on the intrinsic properties of manganese oxides, providing new insights into the optimal design of transition metal oxide interfacial assemblies for efficient catalytic reactions.