Studies on electrocatalytic degradation of Malachite green dye using Zn0.5Co2.5O4/N-doped rGO nanocomposite coated stainless steel electrode

Abstract

This study investigates the electrocatalytic degradation of Malachite Green dye using different nanocatalysts coated on stainless steel mesh. Nanocrystalline Zn0.5Co2.5O4/N-doped rGO composite was prepared via hydrothermal method. The phase purity, morphological and structural features were assessed using characterization techniques namely XRD and TEM analysis. Catalyst coated stainless steel electrode were employed for the electrocatalytic degradation of Malachite Green (MG) dye in 10mM NaCl electrolyte with application of potential and a current of 20V and 20mA respectively. The effect of NaCl electrolyte on the degradation rate have been studied. The decrease in the intensity of dye color was monitored by UV Visible spectrometer at different intervals of time. Malachite Green dye was completely degraded using these electrodes at 60 minutes. At 15 and 30 minutes, Zn0.5Co2.5O4/N-doped rGO composite coated stainless steel electrode showed higher rate over the uncoated stainless steel electrode. The products formed after electrocatalytic degradation were analyzed by Liquid Chromatography-Mass Spectrometry (LCMS). The effect of the catalyst on the degradation rate was monitored and studied. The results were promising as the catalyst coated stainless steel electrode took less time compared to uncoated stainless steel electrode for the degradation of Malachite Green dye. The catalyst coated on the stainless steel mesh provides high surface area and better contact between catalysts and dye molecules with high electrochemical activity. This widens its applications for remediation of various textile effluents.