Electrochemical synthesis of Pt-decorated Au dendrite anode for constructing a direct formic acid fuel cell

Abstract

Scale-up fabrication of electrodes using a facile method is a challenge for the commercialization of direct formic acid fuel cells (DFAFCs). Herein, we report the facile fabrication of a Pt-decorated Au dendrite (Pt@Au-D) anode for DFAFCs. The Au dendrite was prepared by the galvanic displacement of Au on Ni-deposited carbon paper (CP) with a geometrical area of 10.2 cm2. The Pt islands were then electrodeposited on the Au dendrite with an extremely low Pt loading of 9.6 ± 0.1 μgPt/cm2. The Pt@Au-D/CP showed a current density of 27.1 mA/cm2 at 0.5 VRHE in an electrolyte consisting of 0.5 M HCOOH +0.5 M H2SO4, which was higher than those of state-of-art Pt–Au catalysts. Pt@Au-D/CP was employed as the anode for a DFAFC single cell coupled with a commercial Pt/C/CP cathode. The DFAFC single cell demonstrated a current density of 67.6 mA/cm2 at 0.4 Vcell and a maximum power density of 65.2 mW/cm2. Compared with state-of-the-art Pt–Au anodes, the Pt@Au-D/CP anode exhibited superior mass activity.