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.@en

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 Ti3C2Tx (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.@en

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.@en