Carbon Capture Science & Technology (Sep 2023)
Effect of temperature and pressure on electrochemical CO2 reduction: A mini review
Abstract
The conversion of CO2 into high-value fuels and chemicals through electrochemical CO2 reduction reaction (CO2RR) might be one effective way to control current effects of greenhouse gas emissions. However, the slow kinetics and side reactions involved in the process of CO2RR lead to low selectivity, inactivity and limited durability. Additionally, CO2RR is less selective for hydrocarbons due to interference by the hydrogen evolution reaction (HER) and the multiple electron transfer processes involved in the reaction process. In fact, CO2RR is sensitive to the dynamic changes of the catalyst and non-catalyst components (i.e. the reaction micro-environment) at the electrode/electrolyte interface. These factors regulate the transportation of reactive substances, and also affect the intermediates and the paths of the electrocatalytic reaction. There is a large body of literature in this field that focuses on the structure (chemical state, composition, crystal surface and morphology) of the electrocatalyst for CO2RR. Although the impact of the reaction conditions (including temperature and pressure) on CO2RR should not be underestimated, to date, few studies have been done on this aspect. In this mini review, we first describe the evaluation parameters, the current mainstream catalysts and then, by focusing on the effect of temperature and pressure in the CO2RR, elucidate on its controlling influence on the performance of CO2RR. Finally, current problems and future development trends are summarized. We suggest that this review may provide some theoretical basis for the design of catalytic CO2RR processes.
