Abstract
The electrochemical reduction in CO(2) (CO2RR) to syngas and value-added hydrocarbons offers a promising route for sustainable CO(2) utilization. This work develops tuneable Cu-Sn bimetallic catalysts via electrodeposition, optimized for CO2RR in a zero-gap flow cell fed with CO(2)-saturated KHCO(3) solution, a configuration closer to industrial scalability than conventional H-cells. By varying electrodeposition parameters (pH, surfactant DTAB, and metal precursors), we engineered catalysts with distinct selectivity profiles: Cu-Sn(B), modified with DTAB, achieved 50% Faradaic efficiency (FE) to CO at -2.2 V and -50 mA·cm(-2), outperforming Ag-based systems that require higher overpotentials. Meanwhile, Cu-Sn(A) favoured C(2)H(4) (35% FE at -100 mA·cm(-2)), and Cu-Sn(C) shifted selectivity to CH(4) (26% FE), demonstrating product tunability. The catalysts' performance stems from synergistic Cu-Sn interactions and DTAB-induced morphological control, as revealed by SEM/EDX and electrochemical analysis. Notably, all systems operated at lower voltages than literature benchmarks while maintaining moderate CO(2) utilization (32-49% outlet). This study highlights the potential of electrodeposited Cu-Sn catalysts for energy-efficient CO2RR, bridging the gap between fundamental research and industrial application in syngas and hydrocarbon production.