A review of catalysts for the electroreduction of carbon dioxide to produce low-carbon fuels

Abstract

This paper reviews recent progress made in identifying electrocatalysts for carbon dioxide (CO2) reduction to produce low-carbon fuels, including CO, HCOOH/HCOO(-), CH2O, CH4, H2C2O4/HC2O4(-), C2H4, CH3OH, CH3CH2OH and others. The electrocatalysts are classified into several categories, including metals, metal alloys, metal oxides, metal complexes, polymers/clusters, enzymes and organic molecules. The catalyts' activity, product selectivity, Faradaic efficiency, catalytic stability and reduction mechanisms during CO2 electroreduction have received detailed treatment. In particular, we review the effects of electrode potential, solution-electrolyte type and composition, temperature, pressure, and other conditions on these catalyst properties. The challenges in achieving highly active and stable CO2 reduction electrocatalysts are analyzed, and several research directions for practical applications are proposed, with the aim of mitigating performance degradation, overcoming additional challenges, and facilitating research and development in this area.

CO2 Reduction: From the Electrochemical to Photochemical Approach

“…Several previous high‐quality review articles on similar topics are available 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26. Given the recent heightened research activities and increasingly deepened understanding of these two processes, we believe that an up‐to‐date account on their status and existing challenges is necessary so as to provide readers with a current snapshot of this rapidly evolving area.…”

Dye-sensitized PS- b -P2VP-templated nickel oxide films for photoelectrochemical applications

“…Alternatively, coupling photocatalytic water oxidation with the reduction of CO 2 produces carbon-based fuels, with a net zero-carbon footprint. A number of molecular and supramolecular photocatalytic systems for H 2 evolution, CO 2 reduction or water oxidation have been reported during the last decade [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. These systems however only achieve one-half of the targeted process and require the use of sacrificial components to furnish or accept the electrons required or produced by the catalytic reaction, respectively.…”

Production of methanol from CO2 electroreduction at Cu2O and Cu2O/ZnO-based electrodes in aqueous solution

“…Unfortunately, among the many electrocatalytic materials previously investigated for CO2 reduction, none of them are both efficient and selective, and the most common products are CO and HCOOH, which are not as readily used as fuels as hydrocarbons or alcohols are [10]. Among the studied materials, copper (Cu), molybdenum (Mo) and ruthenium (Ru), as well as their mixtures and oxidized forms [11,[15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30], have been reported to be the most active materials for the electrochemical transformation of CO2 to CH3OH.…”

“…The electrochemical route of CO2 reduction is known to produce a variety of useful products, which mainly depend on the catalyst materials, and the reaction medium employed [10]. The major reduction products are carbon monoxide (CO), formic acid (HCOOH), formaldehyde (CH2O), methanol (CH3OH), oxalic acid (H2C2O4), methane (CH4), ethylene (CH2CH2) or ethanol (CH3CH2OH) [9][10][11].…”

“…The major reduction products are carbon monoxide (CO), formic acid (HCOOH), formaldehyde (CH2O), methanol (CH3OH), oxalic acid (H2C2O4), methane (CH4), ethylene (CH2CH2) or ethanol (CH3CH2OH) [9][10][11]. Among these possible reduction products, CH3OH, with relatively high energy density and stable storage properties, is regarded as a feasible approach and recent progress has been made in developing new solutions to enhance its yield and efficiency in the electrochemical reduction of CO2 [7,12].…”