Experimental investigation of electrochemical carbon dioxide reduction reaction for C1 products with diatomic copper manganese electrocatalyst

• Main Author: Hee, Zachary An
• Other Authors: Alex Yan Qingyu
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Materials
• Online Access: https://hdl.handle.net/10356/166630
• Institution: Nanyang Technological University

Using copper as a homonuclear single-atom catalyst, or SAC, as a cathode in an electrochemical cell, increases the selectivity and faradaic efficiency. However, it does not produce enough CO2 reduction reaction activity, or CO2 RR. A higher activity of CO2RR means higher amount of CO2 gas used in the reaction to produce chemical products such as formic acid. Substituting a homonuclear SAC with a hetero-diatomic catalyst, it produces unique catalytic properties like higher faradaic efficiency and performance. Adding manganese with copper as a hetero-diatomic catalyst, manganese can suppress the water reduction reaction for more CO2 reduction activity to occur. Gas chromatography, or GC, will be used to evaluate the gas products, and nuclear magnetic resonance spectroscopy, or NMR Spectroscopy, will be used to test the liquid products. Each catalyst will be applied with a different potential for a specific duration. With the lab test results, it will reveal that heteronuclear copper-manganese-nitrogen-carbon (Cu-Mn-N-C) catalyst is the best at producing higher activity and products’ selectivity among nitrogen-carbon (N-C), copper-nitrogen-carbon (Cu-N-C), and manganese-nitrogen-carbon (Mn-N-C) catalyst samples. Producing the highest carbon monoxide (CO) partial current density at 33.68 mA cm-2 at -0.875 VRHE, with an average of 20.63 mA cm-2 over a range of -0.475 to -1.175 VRHE. The SEM images which have shown no difference in geometry structure can be proven that it is not a mechanism behind the hetero-diatomic Cu-Mn-N-C’s high performance when compared to the other SAC samples.