電化學二氧化碳還原反應(CO2RR)為將二氧化碳轉化為有價值的化學燃料和解決全球暖化提供了有效的方法。本研究針對優化銅錫奈米觸媒以獲得最佳的CO2RR效能。以油胺法製備銅錫奈米觸媒並利用能量散射光譜儀(EDS)、感應耦合電漿質譜分析儀(ICP-MS)、X光繞射分析儀(XRD)、X光光電子光譜(XPS)做觸媒特性鑑定。電催化性能藉由電流密度和主要產物一氧化碳法拉第效率來檢驗。透過調整適當銅錫比例來優化銅錫奈米觸媒的化學性質；Cu98Sn2/C在-0.7 V (vs. RHE)下表現出54.0%一氧化碳法拉第效率的最佳活性。觸媒結構的物理性質受合成溫度控制；於493 K下合成出均勻分散在表面的銅和錫，在-0.8 V (vs. RHE)下有最高的一氧化碳法拉第效率88.6%。此外，對兩種錫前驅物做比較發現在油胺法中使用二水氯化亞錫於合成上是更好的選擇。

Electrochemical carbon dioxide reduction reaction (CO2RR) provides an effective way to convert carbon dioxide into valuable chemical fuels and resolve the detrimental problem of global warming. Our present work aims to optimize CuSn nanocatalysts for achieveing the best CO2RR performance. CuSn nanocatalysts were synthesized by oleylamine method and characterized by various technqies, including EDS, ICP-MS, XRD and XPS. The electrocatalytic performance was examined by current density and Faradiac efficiency (FE) of CO, the main reduction product. The chemical character of CuSn nanocatalysts was optimized by adjusting the proper Cu/Sn ratio; Cu98Sn2/C showed the best activity of 54.0% CO FE at -0.7 V (vs.RHE). The physical character of catalyst structure was controlled by the synthetic temperature; evenly dispersed surface Cu and Sn, synthesized at 493 K, had the highest CO FE of 88.6% at -0.8 V (vs. RHE). Addtionally, couple tin precursors were examined and found that dehydrated tin(II) chloride is a better option for the synthesis in oleylamine method.

1. Zheng, Y., et al., Advancing the electrochemistry of the hydrogen‐evolution reaction through combining experiment and theory. Angewandte Chemie International Edition, 2015. 54(1): p. 52-65.
2. Wu, J., et al., CO2 reduction: from the electrochemical to photochemical approach. Advanced Science, 2017. 4(11): p. 1700194.
3. Kortlever, R., et al., Catalysts and reaction pathways for the electrochemical reduction of carbon dioxide. The journal of physical chemistry letters, 2015. 6(20): p. 4073-4082.
4. Zhou, J.-H. and Y.-W. Zhang, Metal-based heterogeneous electrocatalysts for reduction of carbon dioxide and nitrogen: mechanisms, recent advances and perspective. Reaction Chemistry & Engineering, 2018. 3(5): p. 591-625.
5. Greeley, J., et al., Computational high-throughput screening of electrocatalytic materials for hydrogen evolution. Nature materials, 2006. 5(11): p. 909-913.
6. Kuhl, K.P., et al., Electrocatalytic conversion of carbon dioxide to methane and methanol on transition metal surfaces. Journal of the American Chemical Society, 2014. 136(40): p. 14107-14113.
7. Malkani, A.S., M. Dunwell, and B. Xu, Operando spectroscopic investigations of copper and oxide-derived copper catalysts for electrochemical CO reduction. ACS Catalysis, 2018. 9(1): p. 474-478.
8. Chen, C., et al., Efficient electroreduction of CO2 to C2 products over B-doped oxide-derived copper. Green Chemistry, 2018. 20(20): p. 4579-4583.
9. Lee, C.W., et al., Defining a materials database for the design of copper binary alloy catalysts for electrochemical CO2 conversion. Advanced Materials, 2018. 30(42): p. 1704717.
10. Huang, J., et al., Structural sensitivities in bimetallic catalysts for electrochemical CO2 reduction revealed by Ag–Cu nanodimers. Journal of the American Chemical Society, 2019. 141(6): p. 2490-2499.
11. Hsieh, Y.-C., et al., Effect of chloride anions on the synthesis and enhanced catalytic activity of silver nanocoral electrodes for CO2 electroreduction. ACS Catalysis, 2015. 5(9): p. 5349-5356.
12. Kim, J., et al., Branched copper oxide nanoparticles induce highly selective ethylene production by electrochemical carbon dioxide reduction. Journal of the American Chemical Society, 2019. 141(17): p. 6986-6994.
13. Zhang, W., et al., Electronic and geometric structure engineering of bicontinuous porous Ag–Cu nanoarchitectures for realizing selectivity-tunable electrochemical CO2 reduction. Nano Energy, 2020. 73: p. 104796.
14. Hoshi, N., M. Kato, and Y. Hori, Electrochemical reduction of CO2 on single crystal electrodes of silver Ag (111), Ag (100) and Ag (110). Journal of electroanalytical chemistry, 1997. 440(1-2): p. 283-286.
15. Hori, Y., et al., Selective formation of C2 compounds from electrochemical reduction of CO2 at a series of copper single crystal electrodes. The Journal of Physical Chemistry B, 2002. 106(1): p. 15-17.
16. Vasileff, A., et al., Selectivity control for electrochemical CO2 reduction by charge redistribution on the surface of copper alloys. ACS Catalysis, 2019. 9(10): p. 9411-9417.
17. Sarfraz, S., et al., Cu–Sn bimetallic catalyst for selective aqueous electroreduction of CO2 to CO. ACS Catalysis, 2016. 6(5): p. 2842-2851.
18. Shao, Q., et al., Advanced engineering of core/shell nanostructures for electrochemical carbon dioxide reduction. Journal of Materials Chemistry A, 2019. 7(36): p. 20478-20493.
19. Luo, M. and S. Guo, Strain-controlled electrocatalysis on multimetallic nanomaterials. Nature Reviews Materials, 2017. 2(11): p. 1-13.
20. Beermann, V., et al., Rh-doped Pt–Ni octahedral nanoparticles: understanding the correlation between elemental distribution, oxygen reduction reaction, and shape stability. Nano letters, 2016. 16(3): p. 1719-1725.
21. Hu, H., et al., Thermal‐Treatment‐Induced Cu− Sn Core/Shell Nanowire Array Catalysts for Highly Efficient CO2 Electroreduction. ChemElectroChem, 2018. 5(24): p. 3854-3858.
22. Li, Q., et al., Tuning Sn-catalysis for electrochemical reduction of CO2 to CO via the core/shell Cu/SnO2 structure. Journal of the American chemical society, 2017. 139(12): p. 4290-4293.
23. Feaster, J.T., et al., Understanding selectivity for the electrochemical reduction of carbon dioxide to formic acid and carbon monoxide on metal electrodes. Acs Catalysis, 2017. 7(7): p. 4822-4827.
24. Peng, X., S.G. Karakalos, and W.E. Mustain, Preferentially oriented Ag nanocrystals with extremely high activity and faradaic efficiency for CO2 electrochemical reduction to CO. ACS applied materials & interfaces, 2018. 10(2): p. 1734-1742.
25. Chen, C.S., et al., Stable and selective electrochemical reduction of carbon dioxide to ethylene on copper mesocrystals. Catalysis Science & Technology, 2015. 5(1): p. 161-168.
26. Zhou, J.-H., et al., Thin-walled hollow Au–Cu nanostructures with high efficiency in electrochemical reduction of CO2 to CO. Inorganic Chemistry Frontiers, 2018. 5(7): p. 1524-1532.
27. Xie, H., et al., Boosting Tunable Syngas formation via electrochemical CO2 reduction on Cu/In2O3 core/shell nanoparticles. ACS applied materials & interfaces, 2018. 10(43): p. 36996-37004.
28. Peng, L., et al., Self-growing Cu/Sn bimetallic electrocatalysts on nitrogen-doped porous carbon cloth with 3D-hierarchical honeycomb structure for highly active carbon dioxide reduction. Applied Catalysis B: Environmental, 2020. 264: p. 118447.
29. Wu, Y., et al., Sn Atoms on Cu Nanoparticles for Suppressing Competitive H2 Evolution in CO2 Electrolysis. ACS Applied Nano Materials, 2021.
30. Li, Q., et al., Tuning Sn-Cu Catalysis for Electrochemical Reduction of CO2 on Partially Reduced Oxides SnOx-CuOx-Modified Cu Electrodes. Catalysts, 2019. 9(5): p. 476.
31. Wang, P., et al., Phase and structure engineering of copper tin heterostructures for efficient electrochemical carbon dioxide reduction. Nature communications, 2018. 9(1): p. 1-10.
32. Dong, W.J., et al., Evidence of Local Corrosion of Bimetallic Cu–Sn Catalysts and Its Effects on the Selectivity of Electrochemical CO2 Reduction. ACS Applied Energy Materials, 2020. 3(11): p. 10568-10577.
33. Zhao, Y., C. Wang, and G.G. Wallace, Tin nanoparticles decorated copper oxide nanowires for selective electrochemical reduction of aqueous CO2 to CO. Journal of Materials Chemistry A, 2016. 4(27): p. 10710-10718.
34. Zeng, J., et al., Advanced Cu-Sn foam for selectively converting CO2 to CO in aqueous solution. Applied Catalysis B: Environmental, 2018. 236: p. 475-482.