Linking microscopic structural units to macroscopic performance: MnO6 connectivity as a structural regulator of oxygen dynamics in VOC oxidation

Although manganese-based oxides (MnO x ) are promising catalysts for the combustion of volatile organic compounds (VOCs), a fundamental understanding of the intricate relationship between their atomic-scale structure and catalytic activity remains elusive. Here, a series of Mn-based oxides with distinct local coordination environments (MnO 2 , Mn 2 O 3 , LaMnO 3 , and Mn 3 O 4 ) was synthesized to examine the structure–oxygen dynamics–activity relationship in VOC oxidation within a Mars–van Krevelen (MvK) framework. Across this series, VOC oxidation performance was more consistently associated with oxygen-release and redox behavior than with individual static surface descriptors. MnO 2 combines a more heterogeneous, less uniformly constrained Mn–O network with a larger accessible oxygen reservoir and a more favorable low-temperature reduction response, which together are associated with its superior catalytic performance. By contrast, Mn 2 O 3 , LaMnO 3 , and Mn 3 O 4 show less favorable oxygen-release, reduction responses and lower catalytic performance. These results identify MnO 6 connectivity as a structural feature associated with the oxygen-release and redox characteristics relevant to MvK oxidation. In-situ DRIFTS further revealed that MnO 2 accelerated the formation and consumption of enolic intermediates during acetone oxidation, thereby limiting intermediate accumulation and promoting deep oxidation. Overall, the combined results support a connectivity-centered interpretation of the MvK process, in which MnO 6 connectivity provides an upstream structural context for oxygen delivery and redox cycling, whereas oxygen dynamics constitutes the more immediate mechanistic link to VOC oxidation performance. This connectivity-centered perspective provides a structural basis for tuning the redox properties of Mn-based oxides and supports the development of efficient catalysts for VOC emission control.