فهرست نشریات علمی دسترسی آزاد ایران

ZrO2/NiO nanocomposite (NC) was prepared using Spathodea campanulata leaf extract by solution combustion technique, and the as-prepared NC was used as an adsorbent for the Congo Red dye removal analysis in pH 2.0 under pseudo-first and second order conditions. The ZrO2/NiO was characterized by analytical and electrochemical techniques. Several parameters, including the effect of catalyst dosage and dye concentration, pH, temperature, and time, were investigated. The optimal conditions for successful CR removal are pH 2.0, CR concentration of 5 mg/L, and nanocomposite dosage of 30 mg/L in 180 min. The best linear fit of the adsorption isotherm model suggests the physical (monolayer adsorption) process between the dye and the adsorbent. The correlation coefficient (R2) value was found to be 0.981, and maximum CR dye removal (20.833 mg/g) was found. In kinematic experiments, the second-order model was followed (R2 = 0.995). The ZrO2/NiO NC modified glassy carbon electrode showed excellent detection ability towards dopamine with a limit of detection value of (LOD: 0.033 μM). Desorption investigations revealed that the nanocomposite may be effectively reused up to 5 times. Based on the experimental evidence, a suitable dye adsorption on ZrO2/NiO NC as well as oxidation of DA at ZrO2/NiO NC@GCE was proposed.