Electrodeposition of Nickel on Stainless Steel Electrode and its Application forOxygen Evolution Reaction

the oxygen evolution reaction (OER) is the anodic reaction that accompanies, in aqueouselectrolytes, commerically important cathodic processes such as metal electrowinning andhydrogen production via alkaline water electrolysis. For the latter process, the anodic overpotentialis the major factor in limting operational efficiency [1, 2]. The optimal oxygen evolution anodematerials are RuO2 and IrO2, since these oxides exhibit the lowest overpotentials for the reaction atpractical current densities. The high cost of these materials and their poor long term stability inalkaline solution, renders their widespread commercial utilization both uneconomical andimpractical [3, 4]. Nickel and its alloys have therefore become the anodes of choice for waterelectrolysis [1, 3]. The electrodeposition method is a way to overcome the cost problem of noblemetal catalysts, makes catalysts that are deposited directly on the surface of the substrate.In this work a nickel modified stainless steel electrode was prepared using electrodepositionmethod in micellar solution containing Ni2+ ions. electrodeposition was done by two methods,containing potentiodynamic and potentiostatic methods. The OER was carried out by thesemodified steel electrods using linear sweep voltammetry method. Effect of some experimentalparameter such as surfactant concentration, potential for Ni electrodeposition, time of Nielectrodeposition, number of potential cycling for Ni electrodeposition, on electrode response wasstudied. Resulting modified electrode was characterized by SEM images. The OER is significantlyenhanced upon modification of the electrodes, as demonstrated by a negative shift in the LSVcurves at the Ni modified electrodes compared to that obtained at the unmodified ones. The valuesof energy saving of oxygen gas at a current density of 10 mAcm−2 for electrodes prepared bypotentiodynamic and potentiostatic methods in optimized condition are 16.0, and 21.6 kWh kg−1,respectively. These modified electrodes are very low cost and very stable even after 400 potentialcycling in alkaline solution.

کلیدواژه ها:

Oxygen Evolution ، Electrodeposition ، Nickel ، Surfactant