Electroless CuNiSn electrocatalyst supported on carbon fabric for electrochemical reduction of CO2

Abstract

In the present work, tri-metallic alloy electrocatalysts containing copper (Cu), nickel (Ni), and tin (Sn) supported on Pd-catalyzed carbon fabric substrate were prepared through a simple electroless deposition method. As-deposited Cu-Ni-Sn electrocatalyst was employed in the CO2-ERR in an H-cell type reactor. For the effect of electroless deposition time (15, 30 and 45 mins) on tri-metallic alloy electrocatalyst, the result showed that there is no significant difference for all samples based on the XRD pattern, indicating the deposition time had no effect on the crystalline structure of all catalyst. In addition, the evaluation of the ability of the CO2-ERR on trimetallic alloy electrocatalyst at different times was investigated using LSV. CuNiSn/CS_30 has a higher catalytic activity than CuNiSn/CS_45 and CuNiSn/CS_15 respectively. Furthermore, the Faradaic efficiency and H2 production of the Cu-Ni-Sn alloy electrode was lower than that of the monometallic and bimetallic electrocatalysts, suggesting Cu-Ni-Sn alloy electrode was active in the CO2-ERR. The CO2-ERR using the Cu-Ni-Sn alloy electrode was studied at the applied potential -1.6 V vs. Ag/AgCl. The gaseous products were analyzed by gas chromatography (GC) but an undesired by-product, hydrogen was also produced. For, CuSn/CS_30 and Cu/CS_30 produce gas products with CO other than H2 compared to other electrocatalysts. Thus, most of CO on CuSn/CS_30 and CuSn/CS_30 can be easily converted into formate, C2 product and C3 product. Overall, this work provides new insights into the further development of low-cost non-noble electrocatalysts by a simple electroless deposition method.