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Electrochemical conversion of CO 2 requires selective catalysts and high solubility of CO 2 in the electrolyte to reduce the energy requirement and increase the current efficiency. In this study, the CO 2 reduction reaction (CO 2 RR) over Ag electrodes in acetonitrile-based electrolytes containing 0.1 M [EMIM][2-CNpyr] (1-ethyl-3-methylimidazolium 2-cyanopyrolide), a reactive ionic liquid (IL), is shown to selectively (>94%) convert CO 2 to CO with a stable current density (6 mA•cm −2 ) for at least 12 h. The linear sweep voltammetry experiments show the onset potential of CO 2 reduction in acetonitrile shifts positively by 240 mV when [EMIM][2-CNpyr] is added. This is attributed to the pre-activation of CO 2 through the carboxylate formation via the carbene intermediate of the [EMIM] + cation and the carbamate formation via binding to the nucleophilic [2-CNpyr] − anion. The analysis of the electrode−electrolyte interface by surface-enhanced Raman spectroscopy (SERS) confirms the catalytic role of the functionalized IL where the accumulation of the IL-CO 2 adduct between −1.7 and −2.3 V vs Ag/Ag + and the simultaneous CO formation are captured. This study reveals the electrode surface species and the role of the functionalized ions in lowering the energy requirement of CO 2 RR for the design of multifunctional electrolytes for the integrated capture and conversion.

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Converting CO2 to renewable fuels via clean and cost‐effective chemical processes is very desirable for the sustainable development of green civilization. The electrochemical CO2 reduction (ECO2R) to ethanol using renewable energy is a green and effective strategy for addressing global warming and energy shortage issues. But, simultaneous generation of multiple gaseous & liquid products and low catalytic activities are limiting the technology‘s practical use in the short term. In this study, recent scientific developments in ECO2R for selective production of ethanol are reviewed which include both theoretical and experimental aspects. The reported electro‐catalysts are categorized into different groups and the performance of these electro‐catalysts/electrodes is summarized. The effect of electro‐catalysts’ composition & its morphology, applied potential, type of electrolyte, metal loading, reactor configuration, etc. are comprehensively summarized. Furthermore, the present status & challenges and future prospects are presented to help in future design and planning of high‐performance electro‐catalysts for ethanol.