Oxygen‐Doped Graphitic Carbon Nitride for Electrochemical Uric Acid Sensing: Method Without Metals

Abstract

The present study examined potential benefits of heteroatom doping to manipulate the electrical structure and to enhance the efficiency of the sensor, with an emphasis on developing inexpensive, metal‐free electrochemical sensors. Melamine and ammonium oxalate were used as precursors in a one‐step thermal polymerization technique yielding oxygen‐doped graphitic carbon nitride (O‐gCN). Following synthesis, the material's structural and morphological properties were thoroughly examined using a multitude of analytical techniques, including EIS. A notable decrease in impedance was observed, suggesting improved conductivity. Additionally, the doping approach exhibited a noticeable improvement in reduction current receptivity and surface area as compared to unmodified graphitic carbon nitride (g‐CN). Utilizing both differential pulse voltammetry (DPV) and the classical cyclic voltammetry (CV) methods, we investigated the electro oxidation of uric acid (UA) as well as concentration dependence and selectivity studies using oxygen‐doped graphitic carbon nitride modified glassy carbon electrode (O‐gCN@GCE). O‐gCN@GCE demonstrated remarkable performance, allowing the detection of UA concentrations as low as 7.784 µAµM−1cm−2. Its low detection limit of 0.57 µM and wider linear range (5–120 µM) further highlighted its potential for extremely sensitive assays and its remarkable capacity to operate over a broad UA concentration range.