A.R. Nihmiya^1,*,, R.M.H.H. Jayarathne^1, and A.H.L.R. Nilmini^2,

¹Department of Civil and Environmental Technology, Faculty of Technology, University of Sri Jayewardenepura, Homagama, Sri Lanka

²Department of Materials and Mechanical Technology, Faculty of Technology, University of Sri Jayewardenepura, Homagama, Sri Lanka

*Corresponding author: Tel: +94 76 6223340; E-mail: nihmiya@sjp.ac.lk

Various methods have been suggested to address the problem of elevated levels of carbon dioxide (CO₂) in the atmosphere. A potential technique among these strategies is the electrochemical reduction of CO₂ (ERC), which can simultaneously solve issues like CO₂-induced global warming and enable sustainable energy storage. The ERC procedure takes place within an electrochemical cell at the interface between an ionic conductor (the electrolyte) and an electron conductor (the cathode). In this process, the anode facilitates the oxidation of water, while the cathode enables CO₂ reduction. However, a significant challenge in the ERC process lies in selecting an appropriate catalyst for the cathode material. In addition to explore the new transition metals, researchers have also investigated metal complex catalysts and nanostructures to enhance catalyst activity and product selectivity. Non-aqueous electrolytes have been employed to avoid the hydrogen evolution reaction. Ionic liquids have been proposed as a solution to address the challenge of low CO₂ solubility in the reaction medium, offering significant potential for enhancing conversion rates to resolve the limitations faced by aqueous and non-aqueous systems solid polymer electrolytes are being considered. The cell configuration has been continuously improved to improve the mass transfer effects and to better separate the reaction products. This review paper provides a preface to the ERC process and an inclusive review of several decades of research work on ERC process by analyzing the adopted various and novel cathode materials, electrolytes and cell configuration.

Carbon dioxide, Electrochemical reduction, Catalyst, Electrodes, Electrolyte.