Catalytic Activation of Molecular Oxygen Toward Producing Hydroxyl Radicals Controllably for Highly Selective Oxidation of Hydroxyl Compounds under Mild Conditions
Xin Liu, Hong Ma, Meiyun Zhang, Penghua Che, Yang Luo, Shujing Zhang, Jie Xu
Abstract
Hydroxyl radicals (OH • ), as one of the most highly oxidizing oxidants, are difficult to utilize in chemical synthesis since they usually cause unavoidable oxidative damage with CO 2 released. Here, a Co–N–C nanomaterial composed of CoN 4 sites on graphitic carbon nitride was constructed, which fulfills the self-cascade activation of O 2 in water, wherein OH • is guided to generate in a controlled level and exerts a highly selective oxidation role for efficient synthesis of a variety of organic acids by oxidation of furan alcohols, aromatic alcohols, and fatty alcohols under mild conditions. 5-Hydroxymethylfurfural (HMF) reached >99.9% conversion with 94.2% yield of 2,5-furandicarboxylic acid (FDCA) at 25 °C under atmospheric O 2 pressure. This study allows a promising utility of O 2 in a low energy-consuming way independent of light or electricity.