Effect of peptide aerogel composite on silver nanoparticles as a catalyst for electrochemical CO₂ reduction

Abstract

Electrochemical reduction of carbon dioxide (CO2RR) product distribution has been found to be dependent on several key factors, such as catalyst surface morphology, stability, and porosity. Metal-modified carbon-based materials have received a lot of attention in CO2RR. However, designing a highly active metal carbon catalyst for CO2RR utilizing low-cost chemical precursors remains a challenge. Here, a series of myristic acid-Phe-Phe peptide (MA-FF) aerogel materials containing graphene oxide (Gox) and Ag nanoparticles have been prepared for electrochemical CO2RR. The morphologies of the composites were studied by scanning electron microscopy (SEM), and their surface compositions were determined using X-ray photoelectron spectroscopy (XPS). While the peptide aerogel alone showed no catalytic activity for CO2 electroreduction, the addition of Ag nanoparticles results in a Faradaic efficiency (FE) of 46% for electroreduction of CO2 to CO at an overpotential of − 0.8 V vs. RHE. Incorporation of Gox in the aerogel increases the FE to 88% and allows CO2 reduction at a lower overpotential of − 0.7 V vs. RHE. Using highly porous peptide aerogels-Gox in addition to the metal active center provides an enhanced and new method for CO2 conversion using low environmental impact bio-based aerogels.