Galvanostatic Electroshock Synthesis of Low Loading Au−Pt Nanoalloys Onto Gas Diffusion Electrodes as Multifunctional Electrocatalysts for a Glycerol‐Fed Electrolyzer

Abstract

AbstractWater electrolysis is increasingly considered a viable solution for meeting the world′s growing energy demands and mitigating environmental issues. An inventive strategy to mitigate the energy requirements involves substituting the energy‐intensive oxygen evolution reaction (OER) with biomass‐derived glycerol electrooxidation. Nonetheless, the synthesis of electrocatalysts for controlling the selectivity towards added‐value chemicals at the anode and efficient H2 generation at the cathode remains a critical bottleneck. Herein, we implemented a galvanostatic electroshock synthesis approach to control the reduction kinetics of Au(III) and Pt(IV) to grow ultra‐low amount of gold‐platinum alloys on a gas diffusion electrode (12–26 μgmetal cm−2) for glycerol‐fed hydroxide anion exchange membrane based electrolyzer. The symmetric GDE‐Au100–xPtx||GDE‐Au100–xPtx systems showed a notable improvement in electrolyzer performance (GDE‐Au64Pt36=201 mA cm−2) as compared to monometallic versions (GDE‐Au100Pt0=18 mA cm−2, GDE‐Au0Pt100=81 mA cm−2). Chromatography (HPLC) analysis underscores the critical importance of bulk electrolysis methodology (galvanostatic vs potentiostatic) for the efficient conversion of glycerol into high‐value‐added products. Regarding the electrical energy required to produce 1 kg of H2 for such an electrolyzer fed at the anode with glycerol, our results confirm a drastic decrease by a factor of at least two compared with conventional water electrolysis.