Spatial geometric effect driven by the different [MnO6] octahedra entity stacking configurations to facilitate the catalytic decomposition of H2O2 in wastewater

[Display omitted] •The [MnO6] entity stacking configurations modulate the electronic structures of MnO2.•The edge-sharing stacking mode contributes to the optimal intermediate adsorption.•The activity of δ-MnO2 with single edge-sharing surpassed the other three phases.•The decomposition of H2O2 (0.5 M) is catalyzed by δ-MnO2 in 2 min at 25 °C. Achieving rapid decomposition of H2O2 is crucial for broadening its applications across various fields, as improper disposal or leakage can lead to serious water pollution. In this work, we explore how the octahedral coordination entity [MnO6] stacking configurations in different MnO2 polymorphs (α-, β-, γ- and δ-) affect their catalytic performance towards H2O2 decomposition. Combining experiments and theoretical simulations, we find that the catalytic activity for H2O2 decomposition strongly depends on the [MnO6] stacking configurations, following the order of δ-