Graphene-like materials as an alternative to carbon Vulcan support for the electrochemical reforming of ethanol: Towards a complete optimization of the anodic catalyst

Abstract

This study aims to investigate the viability of using commercial graphene-like materials as Pt based anodic catalyst supports as an alternative to the extended use of carbon Vulcan XC-72, for the ethanol oxidation reaction (EOR). Among the different investigated catalysts, Pt supported on graphene nanoplatelets (GNPs) resulted to be the most active, which was attributed to a combination of a higher BET surface area and a slightly higher amount of nitrogen in comparison with other supports. A higher BET surface area of the support could mean a larger pore volume available to settle the metal particles, whereas a greater amount of nitrogen may improve its electrical conductivity. A complete optimization of the Pt metal loading and Pt-Ni ratio on the final anodic bimetallic catalyst was also performed to prepare a membrane electrode assembly (MEA) for a proton exchange membrane ethanol electrolysis cell (PEMEC). Finally, the metal loading on MEA was optimized towards the production of hydrogen and value-added products resulting from the EOR. The MEA based on the optimized anodic Pt-Ni/GNPs catalyst allow to obtain current density values around 590 mA·cm−2 (at 1.4 V), higher than previous studies based on Pt-Ru and Pt-Sn catalysts supported on Carbon Vulcan.