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.

The electrochemical CO₂ reduction reaction (CO₂RR) is an attractive method to produce renewable fuel and chemical feedstock using clean energy sources. Formate production represents one of the most economical target products from CO₂RR but is primarily produced using post-transition metal catalysts that require comparatively high overpotentials. Here a composition of bimetallic Cu–Pd is formulated on 2D Ti₃C₂T_x (MXene) nanosheets that are lyophilized into a highly porous 3D aerogel, resulting in formate production much more efficient than post-transition metals. Using a membrane electrode assembly (MEA), formate selectivities >90% are achieved with a current density of 150 mA cm⁻² resulting in the highest ever reported overall energy efficiency of 47% (cell potentials of −2.8 V), over 5 h of operation. A comparable Cu-Pd aerogel achieves near-unity CO production without the MXene templating. This simple strategy represents an important step toward the experimental demonstration of 3D-MXenes-based electrocatalysts for CO₂RR application and opens a new platform for the fabrication of macroscale aerogel MXene-based electrocatalysts.

Electrochemical reduction of carbon dioxide (CO2) to valuable materials is a promising approach to suppress atmospheric CO2 levels. In order to bring this strategy to a commercial scale, the design of efficient, cost-effective, and robust catalysts is essential. Current advances in CO2 conversion technology use bimetallic components that enhance electrocatalysis via the introduction of binding site diversity. In this work, Sn-Pd bimetallic aerogels supported by carbon nanotubes (Sn-Pd/CNT) demonstrate selective electroreduction of CO2 to formate in ambient conditions. Amino substituents were introduced as an additional CO2 capture site (Sn-Pd/CNT-NH2), further enhancing the electrocatalytic activity and resulting in 91% formate selectively and a current density of -39 mA cm-2 at -0.4 V vs. RHE. The results demonstrate the potential of alloying Sn with other earth-abundant metals to promote the electrochemical conversion of CO2 to value-added materials. We believe this study provides valuable insights into the intricate relationship of bimetallic aerogels and shows the potential of the -NH2 group as a facilitator for CO2 capture and conversion that will inspire new forays into the development of competitive catalytic systems.