Single-atom FeN4 sites embedded graphene-like carbon as a versatile reinforcing material for electrochemical sensing

Abstract

Despite significant progress, electrochemical sensors still face some challenges, including the rational design of versatile sensing materials and in-depth elucidation of their sensing mechanisms. In this work, we investigated a kind of bio-inspired material, namely single-atom FeN₄ sites embedded graphene-like carbon (FeSA@GC), as a versatile reinforcing material for electrochemical sensing. By integrating the merits of atomically dispersed active sites with highly conductive carbon matrix, the FeSA@GC exhibited desirable catalytic activity and rapid electron-transfer kinetics. Density functional theory calculations further revealed that the FeN₄ active sites within FeSA@GC play a crucial role in substrate activation and catalytic turnover. As a proof-of-concept application, we developed a novel electrochemical device based on FeSA@GC and its further coupling/hybridization modification, which enabled multiplex detection of physiological biomarkers (uric acid, glucose, and pH). Our research is believed to provide a promising guidance for the rational design of versatile sensing material, and promote the application of electrochemical sensing in biomedical field.