What We Currently Know about Carbon‐Supported Metal and Metal Oxide Nanomaterials in Electrochemical CO₂ Reduction

Abstract

Electrochemical reduction of CO 2 is considered important in enhancing the circular-economy design; it can suppress harmful greenhouse-gas emissions while, combined with intermittent renewable energy sources, it can employ the surplus energy for production of important chemicals and fuels. In the process, electrocatalysts play an important role as the mediators of the highly active and selective conversion of CO 2 . Transition and post transition metals and their oxides are an important electrocatalyst group. For practical reasons, these metals need to be applied as nanoparticles supported on highly conducting materials enabling fabrication of 3D electrodes. In this minireview, we focus on gathering our current knowledge on the effects which transition and post transition metal and metal oxide nanoparticles supported on different carbons may have on electrochemical reduction of CO 2 . We focus on literature of studies conducted in aqueous conditions, under as similar conditions as possible, to ensure comparability. This approach enables us to highlight possible support effects and issues that complicate making conclusions on support effects.

Rational Manipulation of Intermediates on Copper for CO2 Electroreduction Toward Multicarbon Products

“…Although catalyst substrates are primarily used to load catalysts and provide electron-conductive channels, their structures also affect CO 2 RR performance, resulting in the so-called "substrate effects." Specifically, the substrates can not only affect the reconstruction of Cu nanoparticles, but also have electronic interactions with active Cu sites [140]. Because of the outstanding chemical and electrochemical stability of carbon materials, they are the most widely used substrates.…”

Bioelectrocatalytic CO2 Reduction by Redox Polymer-Wired Carbon Monoxide Dehydrogenase Gas Diffusion Electrodes

“…Due to the inert nature of CO 2 , an efficient catalyst is crucial to reducing CO 2 for the synthesis of valuable products. So far, substantial research has been put into using abiotic catalysts, such as metals, metal oxides, N-doped carbon materials, and molecular catalysts for electrocatalytic CO 2 reduction. − However, these catalysts are commonly operated under harsh conditions and often suffer from low product specificity due to the competing H 2 evolution reaction. Therefore, considerable efforts are needed for the design and operation of catalysts providing high conversion selectivities .…”

Enhanced Electrocatalytic CO2 Reduction of Bismuth Nanosheets with Introducing Surface Bismuth Subcarbonate

“…However, the electrochemical CO 2 RR to HCOOH still has some issues to be solved, including the inert nature of CO 2 , complicated electron transfers and sluggish reaction kinetics, the parasitic chemical reaction of hydrogen evolution, and poor long-term stability [7][8][9][10][11]. Metal-based catalysts for HCOOH have been widely studied, e.g., Sn, Pb, Hg, Cd, In, Bi, and so on [12,13].…”