Study of biocarbon supported Fe2P particles for HER with energy applications

Abstract

Hydrogen gas (H2) is a molecule with several applications that can be used as clean and renewable fuel to produce electrical energy through its use in fuel cells. Although H2 can be found rarely in its pure form on earth, is possible to obtain it in large quantities from the water electrolysis. In this process, the electrochemical hydrogen evolution reaction (HER) occurs on the surface of a suitable electrocatalyst. Pt is one of the most studied and applied catalyst for HER but its low abundance and high cost discourage it application at large scale. This has stimulated the study of other types of catalysts based on non noble metals with low cost and available in large ammount. In the present work, a Fe2P/activated biocarbon composite sample was prepared from a porous carbon obtained by chemical activation of a lignocellulosic precursor. The prepared electrocatalyst presents good physicochemical and electrochemical properties for its application in HER, showing low overpotential for the hydrogen evolution (54 mV vs. reversible hydrogen electrode) and high Tafel slope of 120 mV dec-1. Future work should aim to improve the electrocatalytic stability of the material and to perform other experiments to elucidate the mechanism by which HER occurs on the electrocatalyst.