Platinum deposition on the nafion membrane by impregnation reduction using nonionic surfactant for water electrolysis – An alternate approach

Platinum (Pt) deposited Nafion® membrane, as cathode, was prepared by impregnation reduction method using nonionic surfactant and their catalytic activity was characterized for hydrogen evolution reaction in a PEMWE (Polymer Electrolyte Membrane Water Electrolyser). The average diameter of the Pt catalyst was reduced when the non-ionic surfactant was used. IrO2 (Iridium Oxide) was used as the anode catalyst. The electrocatalytic properties of the catalysts were investigated by linear sweep voltammetry which showed reduction in the potential of HER (hydrogen evolution reaction) by about 200 mV. The electrochemical active surface area of platinum was calculated from the cyclic voltammetry which demonstrated an increase in surface area and hence the improved performance. SEM investigations showed reduced particle size and uniform distribution. The MEA (Membrane Electrode Assembly) of 4 cm2 coating area, with a loading of 0.4 mg cm−2 Pt and 1.2 mg cm−2 IrO2 was operated as a single cell at 2 V and 80 °C achieving the highest current density of 1.5 A cm−2. Similarly the MEAs of 500 cm2 coating area with the same loading of catalysts in a single cell at 2 V and in a stack of five cells at 10.0 V and 80 °C exhibited the highest current densities of 1.2 A cm−2 and 1.18 A cm−2 respectively.