Channel Confinement Enables K Species with Rich Electrons in α-MnO2 for Water Molecules Activation

作者：Gu, Huayu; Lan, Jintong; Shi, Hongqi; Xie, Bo; Ai, Zhihui; Zhang, Lizhi; Liu, Xiao^*

来源：Advanced Functional Materials, 2024.

DOI：10.1002/adfm.202310720

• catalytic oxidation
• confinement effect
• electron-rich K
• water molecules activation
• alpha-MnO2

Water molecules are actively involved in many catalytic oxidation processes, which require the construction of highly active sites for their activation to accelerate the reaction rate, especially over non-noble metal catalysts. Herein, K species is embeded into the natural 2*2 channel of alpha-MnO2 by a hydrothermal coupled molten salt method, which would make these K species behave in an electron-rich state and provide more electrons for the activation of water molecules. Compared with surface K modification (namely, the electron-deficient K species), channel K confinement can lower the activation energy barrier of H2O dissociation on alpha-MnO2 to generate hydroxyl species with more nucleophilic oxygen atoms, contributing to the superior HCHO catalytic oxidation activity with a fourfold enhancement. The internal relationship among the confined channel, K species, and catalytic performance is systematically elucidated at the molecular level. This work offers a new ion confinement method and opens up new avenues to construct electron-rich metal sites with channel structures for the activation of water molecules.

• 单位
  上海交通大学