Fabricated of Bimetallic Pd/Pt Nanostructure Deposited on Copper Nanofoam Substrate by Galvanic Replacement as an Effective Electrocatalyst for Hydrogen Evolution Reaction
The effective Pd/Pt bimetallic nanofoam catalyst (Pd/Pt NFC) was fabricated on Cu nano-foam substrate. The substrate was electrochemically prepared by copper reduction and covered with Pd/Pt NFC by galvanic replacement reaction in aqueous solutions of Pd (II) and Pt (IV). The catalyst was characterized by SEM, EDX, ICP-OES and EIS techniques. It was tested for the hydrogen evolution reaction (HER) in the acidic media by linear sweep voltammetry (LSV). Among of various compositions, Pd 65 Pt 35 catalyst showed better performance in comparison with pure Pt NFC for HER. The mass activity of noble metals on the Pt NFC and Pd 65 Pt 35 NFC, at the same potential of 300 mV vs. NHE, were about 3.21 mA mg1 Pt and 4.98 mA mg 1 Pt/Pd , respectively. Consequently, proposed catalyst increased HER activity about 1.5 times and decreases Pt loading on the surface and cost of catalyst. The obtained results show that the Volmer-Heyrovsky mechanism controls the HER. The fabricated catalyst showed a good stability for HER by chronoamperometric method.