Effect of temperature for platinum/carbon electrocatalyst preparation on hydrogen evolution reaction

Abstract

This research was carried out to study the effect of preparation temperature of the Pt/C electrocatalyst on the hydrogen evolution reaction (HER). Pt/C electrocatalyst was synthesized using the polyol method in ethylene glycol with 1 M ascorbic acid as a mild reducing agent. The investigated parameter was the temperature, which will vary from room temperature to 120°C. From the cyclic voltammetry (CV), the results showed that the Pt/C electrocatalyst synthesized by the polyol method at room temperature and 60°C cannot promote hydrogen desorption peak compared to other catalysts. The Pt/C catalyst synthesized at 100°C gave the highest electrochemical surface area (ESA) at around 32.59 m2/gPt. From the linear sweep voltammetry (LSV) tested in an acid solution, the Pt/C catalyst synthesized at 100°C exhibited the highest HER activity. The exchange current density, Tafel slope and overpotential at 10 mA/cm2 were around 5.208 mA/cm2, -59.3 mV/dec and -0.277 VSCE, respectively. From the value of Tafel slope: -59.3 mV/dec, it indicated that the mechanism of the 20%Pt/C electrocatalyst synthesized at 100°C catalyst occurs through Heyrovsky mechanism.