Electrochemical Performance of Palladium-Doped Graphitic Carbon Nitride Nanocomposite Material in Detecting Diclofenac Spiked in Lake Water

The increasing human impact on aquatic ecosystems due to the widespread use of pharmaceuticals such as diclofenac calls for the development of innovative and affordable techniques for detecting and quantifying these contaminants in water. Herein, a technique for detecting diclofenac in phosphate buffer and lake water was developed from palladium-doped graphitic carbon nitride (Pd/GCN) deposited on a glassy carbon electrode. The composite material was synthesized by doping palladium into graphitic carbon nitride. The FTIR and XPS results confirmed the doping of palladium onto the graphitic carbon nitride. The specific surface area of modified Pd/GCN is 73.399 m²/g, which is twice as higher than the pristine GCN. SEM results revealed the morphology of pristine GCN displaying flake like structure while the modified graphitic carbon nitride showed the tiny palladium particles attached on the observed on the surface. The cyclic voltammetry analysis indicated an irreversible peak around at an anodic potential of 0.65 V for the oxidation of diclofenac. The reaction mechanism on Pd/GCN was controlled by the mixture of diffusion and adsorption process. The synthesized Pd/GCN exhibited high catalytic activity in the detection of diclofenac in water with a limit of detection of 0.065 µM, in the linear range of 0.1 to 80 µM. The developed sensor has shown great potential for detecting diclofenac in environmental water sources.