Oxidase Mimic Graphdiyne for Efficient Superoxide Generation in Wide pH Ranges

Great effort has been made in exploring techniques and catalysts for O-2(center dot-) production but they always work efficiently in either acidic or base environment. Presented here is the design of a unique oxidase mimic catalyst comprising self-assembled hemin molecules on graphdiyne (hemin/GDY) for efficient O2 center dot- generation in wide pH ranges. Hemin molecules anchor uniformly across the carbon frame of GDY to enable atomic distribution of the active metal sites, delivering a O-2(center dot-) production rate of 35.7 and 2.3 times than that of hemin and hemin/graphene, respectively. In particular, hemin/GDY can efficiently produce O-2(center dot-) in acidic, alkaline, and neutral environments, delivering a wide pH behavior. Its oxidase mimic ability is demonstrated for sensing glutathione molecules in cell assays, exhibiting high selectivity, long linear range. This work opens a promising design strategy toward efficient oxidase mimic catalysts for various applications.