High performing and cost-effective metal/metal oxide/metal alloy catalysts/electrodes for low temperature CO₂ electroreduction

The electrochemical reduction of CO₂ (ERC) has been proved to be both technical and economic feasible. ERC using renewable energies and abandon nuclear/hydroelectric energies can convert CO₂ to low-carbon fuels for energy storage and reducing CO₂ emission as well as promoting waste (gas) recycling/utilization. One of the challenges is to find high electrochemically active, stable, product-selective and cost-effective catalysts for speeding up the electrode kinetics of ERC. Based on these specific requirements for catalysts, quite few of them are practically promising. In this mini-review paper, we try to give an overview of some important researches and the recent progress in ERC catalysts, focusing on the electrochemical characteristics of Cu-, Sn- and Zn-based catalysts for the efficient ERC. The catalysts reviewed in this paper include single pure metal, metal oxide, metal alloys and metal complexes. In recent years, more and more catalysts with novel nanostructures have been reported, such as those with shell-core structure, which exhibit desirable electrocatalytic performance. Moreover, carbon materials, such as carbon nanotube (CNT) and reduced graphene oxide (rGO), have also been explored as desirable catalyst supports in lab-scale studies. In the most recent years, more attention is moved on the fine crystal structures of catalysts, which are found to be quite critical for achieving desirable product selectivity.