Boosting hydrogen and chemicals production through ethanol electro-reforming on Pt-transition metal anodes

The aim of this work is to boost the combined hydrogen and added-values compounds generation (acetaldehyde, acetic acid and ethyl acetate) through ethanol electrochemical reforming using bimetallic anodes. In particular, the influence of the secondary metal on the electrochemical performance as well as on the product distribution was studied. For that purpose, PtX/C electrocatalysts (where X corresponds to Cu, Co, Ni and Ru) were synthesized by the modified polyol method and tested in both half-cell and proton exchange membrane (PEM) cell configurations. Characterization results showed that incorporation of Ni and Co into the Pt matrix enhances the morphological properties of the material, providing smaller crystallite sizes, higher active surface areas and hence, better dispersion when comparing to Ru and Cu-based electrocatalysts. Ethanol oxidation reaction (EOR) was evaluated by cyclic, linear voltammetry and chronopotentiometry assays. PtCo/C and PtNi/C exhibited the highest electrocatalytic activity at high polarization levels, which translate into an improvement of more than 30% (up to 1050 mA cm(-2)) in the hydrogen production and chemical yields. On the other hand, PtRu/C results more advantageous for a lower potential interval (< 0.85 V) promoting the acetic acid production despite sacrificing ethanol conversion. PtCu/C presented the lowest results in both electrochemical performance and product distribution. Such differences in the electrochemical performance can be rationalized in terms of the synergistic effect between both metals (particle size distribution, grade of dispersion and hydrophilic behavior), which demonstrate that the incorporation of a different secondary metal plays an essential role in the EOR development. (c) 2022 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press.

Automated summary

The aim of this study is to enhance the generation of hydrogen and added-value compounds through ethanol electrochemical reforming. The results show that PtCo/C and PtNi/C exhibit the highest electrocatalytic activity, leading to increased hydrogen and chemical yields. PtRu/C is more advantageous for acetic acid production at lower potentials, while sacrificing ethanol conversion. PtCu/C performs the worst in terms of electrochemical performance and product distribution.