Electrochemical Pathways for Carbon Dioxide Conversion into Sustainable Chemical Fuels

Abstract

The increasing concentration of carbon dioxide (CO₂) necessitated the development of sustainable technologies for its conversion into value-added fuels. This study investigated electrochemical pathways for CO₂ reduction, focusing on catalyst performance, applied potential, and electrolyte composition. A quantitative experimental approach was employed using Cu, Ag, and Sn-based electrocatalysts in a three-electrode system. The results indicated that Cu catalysts achieved the highest current density (18.5 mA/cm²) and demonstrated superior selectivity toward methane (35%) and methanol (20%), whereas Ag showed maximum selectivity for CO production (70%). Increasing the applied potential from −0.6 V to −1.0 V enhanced methane formation from 10% to 40% while reducing hydrogen evolution from 42% to 20%. Electrolyte analysis revealed that alkaline media (KOH) produced the highest current density (19.8 mA/cm²) and improved hydrocarbon selectivity, with methane reaching 40% and methanol 25%. However, catalyst stability tests showed a decline in current density from 18.5 to 15.8 mA/cm² over 10 hours, indicating performance degradation. The findings  highlighted the importance of catalyst design, operational optimization, and electrolyte selection in improving CO₂ reduction efficiency. This study provided valuable insights into electrochemical mechanisms and supported the development of sustainable fuel production technologies. The results suggested that further advancements in catalyst stability and system scalability are essential for industrial applications.