Fabrication of tartrazine sensor using zinc oxide/graphitic carbon nitride modified glassy carbon electrode

Tartrazine (Tz) is well-known synthetic dye and widely used in food industry. Despite its potential applications, Tz has some negative impacts on human beings due to the presence of toxicity and pathogenicity. Thus, it becomes essential to determine and keep an eye on the precise quantification of Tz. Electrochemical method-based sensors have received enormous attention because of their fast processing and response. In this work, we have synthesized ZnO rods under a simple synthesis approach. Graphitic carbon nitride (g-C₃N₄) was synthesized using melamine precursor whereas the composite of ZnO@g-C₃N₄ was obtained by a simple room temperature stirring of ZnO and g-C₃N₄. The as fabricated ZnO, g-C₃N₄, and composite of ZnO@g-C₃N₄ were carefully identified by various sophisticated instrumentation techniques viz., powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. These synthesized g-C₃N₄, ZnO, and ZnO@g-C₃N₄ composite have been used for the modification of glassy carbon electrode (GCE) and designated as MGE-2, MGE-3, and MGE-4, respectively, whereas bare GC electrode has been designated as MGE-1. For evaluating the electrochemical sensing performance of the modified electrodes MGE-2, MGE-3, and MGE-4, differential pulse voltammetry (DPV) method has been used. The MGE-4 exhibited the reasonably good detection limit of 0.03 µM and sensitivity of 1.57 µA µM⁻¹ cm⁻².