Metal‐based Heterogeneous Electrocatalysts for Electrochemical Reduction of Carbon Dioxide to Methane: Progress and Challenges

Abstract

Electrochemical reduction of carbon dioxide (CO2ER) has attracted enormous research interest owing to the feasibility to consume the excessive CO2 in atmosphere arising from overconsumption of fossil fuels and store the chemical energy in value‐added chemicals. The conversion of CO2 into methane (CH4) is of great importance, and recent advance has allowed the design and utilisation of effective electrocatalysts with improved electrocatalytic performance regarding product selectivity and Faradaic efficiency. In this mini‐review, we discuss the recent progress and challenges of metal‐based heterogeneous electrocatalyst for CO2ER into CH4 by starting with fundamental mechanisms and designing principles of effective electrocatalysts. In the following sections, we present several successful demonstrations and analyze the effect and contribution arising from their chemical composition, facet, size, and other characters. Some challenges and promising strategies are discussed finally.

New Opportunity for Carbon‐Supported Ni‐based Electrocatalysts: Gas‐Phase CO2 Methanation

“…Both heterogeneous catalysis and electrocatalysis can effectively hydrogenate anthropogenic CO 2 to renewable CH 4 fuel, providing promising pathways to reducing CO 2 emissions [1–5] . The similarity between heterogeneous catalysis and electrocatalysis is notable in that both processes involve sequences of bond breaking and formation [6] .…”

Understanding the complexity in bridging thermal and electrocatalytic methanation of CO2

“…Based on the previous discussion, analysing the proposed design criteria for CO 2 electrocatalytic methanation is now possible. Here, we refer to the criteria indicated by Zhao et al, 344 which are similar to that indicated by other authors for the same reaction 312 or different products in CO 2 electrocatalytic reduction. 355,356 The main strategies indicated for catalyst design are the following:…”

“…However, it indicates that the electrocatalytic CO 2 area is of growing relevance, while direct CO 2 electrocatalytic methanation is still marginally investigated. The number of dedicated reviews is also limited, 312,313 but one of the paths often discussed is related to CO 2 electrocatalytic conversion. [314][315][316][317][318][319][320] On the contrary, the topic of electrocatalytic CO 2 methanation has been rarely addressed in reviews dealing with catalytic CO 2 or CO methanation.…”

Development of catalysts and electrolyzers toward industrial-scale CO2electroreduction

“…1). 12,13 The utilization of photovoltaic and wind power in electrochemical CO 2 RR systems Geng Li is currently a graduate student in Chemistry, City University of Hong Kong. He obtained his bachelor's and master's degrees from Nanjing University of Science and Technology in 2018 and University of Science and Technology of China in 2021, respectively.…”

“…1). 12,13 The utilization of photovoltaic and wind power in electrochemical CO 2 RR systems can simultaneously reduce the atmospheric CO 2 concentration and convert the intermittent and unstable electricity into chemical fuels. Furthermore, as the cost of power generated by photovoltaic systems and wind turbines continues to drop, the electrochemical CO 2 RR is emerging as an attractive and sustainable technique for converting atmospheric CO 2 into fuels and chemicals.…”