A unique VS2 nanosheet decorated metal-organic framework based highly synergistic electrocatalyst for the efficient detection of melamine in food samples

Herein, we design a novel electrocatalyst-based bimetallic (Fe/Cu) Metal-organic Framework intercalated with Vanadium disulfide (VS₂) nanosheet acting as a suitable electrochemical sensor for the detection of Melamine. The MOF@VS₂ nanocomposite was synthesized using a one-step hydrothermal method. The analytical techniques for cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) were used to examine the electrochemical studies of melamine detection. Interestingly, MOF@VS₂ nanocomposite coated with glass carbon electrode utilizes an oxidative pathway to break down melamine, followed by three steps. The initial oxidation reaction converts melamine directly into ammeline. Further, ammeline, undergoing additional oxidation, transforms into ammelide. As a result, the oxidation of ammelide yields cyanuric acid. Based on this mechanism, the proposed electrochemical sensor demonstrated a high oxidation potential of +0.24 V, a wide linear range (10–150 μM), a low detection limit of 0.42 nM, and superior electron transfer kinetics, making it more effective in melamine detection than coexisting molecules. The novel electrocatalyst of MOF@VS₂ nanocomposite brings about a high synergistic effect, good electrical conductivity, and a large surface area. This finding suggests its potential applications as a melamine sensor, particularly in the food safety and healthcare sectors.