Potentiostatic electrodeposition of a novel cost effective PbO2 electrode: Degradation study with emphasis on current efficiency and energy consumption

•Novel method of preparation of a cost effective and efficient electrocatalyst.•Characterisation by SEM, EDX and XRD at varying deposition conditions.•Kinetic analysis of electrochemical degradation at varying oxidation conditions.•Role of direct and mediated electrochemical oxidation at varying applied current.•High current efficiency and low energy consumption for contaminant degradation.

Electrochemical oxidation is developing as a prominent technology for the degradation of organic contaminants. Even though many electrode materials proved efficient in degradation of organics, the quest for a stable, low cost electrode material is still at large. The present study attempted the development of an efficient and cost effective electrode material, PbO2 electrodeposited on mild steel. The optimum operating range of parameters for the electrodeposition was established. Compact structure of PbO2 was obtained up to an applied voltage of 2 V. Concentration of PbO also affected the morphology at lower concentration. XRD analysis depicted that the deposit consists of a mixture of α and β-PbO2, and non-stoichiometry of the deposited PbO2 was proved by EDX analysis. Applied current, initial dye concentration, supporting electrolyte type and concentration affected the reaction kinetics, current efficiency and energy consumption in the degradation of methyl orange on MS/PbO2 electrode. A current efficiency of 57% and corresponding energy consumption of 42 kWh kg COD−1 treated was obtained at 88% COD degradation for an initial COD of 292 mg L−1 with current density of 2.87 mA cm−2. The newly developed MS/PbO2 electrode had current efficiency and energy consumption comparable with data reported in literature at similar degradation conditions.

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