| 摘要: | 近年來，二氧化碳濃度上升，導致全球暖化加劇。因此，透過二氧化碳還原反應(CO2 Electrochemical Reduction Reaction, CO2RR)，將二氧化碳轉化為高附加價值之化學品，可以實現碳中和之目標。本研究以微陽極導引電鍍法(Micro-Anode Guided Electroplating, MAGE)製備銅鋅合金微柱，並探討其在0.1 M KHCO3中進行CO2RR之產物。固定析鍍偏壓為4.6 V、間距控制在40 μm，改變硫酸鋅濃度(0.15 ~ 0.18 M)進行析鍍。合金微柱(Cu74Zn26、Cu66Zn34、Cu63Zn37、Cu55Zn45)經SEM、EDX、XRD分析材料特性。此製程所得微柱具有三維結構，增加催化活性面積。隨後，利用循環伏安法、線性掃描伏安法、電化學交流阻抗頻譜、計時電流法於0.1 M KHCO3下分析其電催化性能，結果顯示：CZ16合金微柱(組成為Cu66Zn34)具有最大之電化學活性表面積(Electrochemical Surface Area, ECSA)為8.7 cm2。此外，在-1.0 V vs. RHE下，具有最小之(乙醇)塔弗斜率(Tafel slope)為185 mV/dec。最後，藉由GC、NMR、FTIR分析CO2RR後之產物。結果顯示：CZ16合金微柱(組成為Cu66Zn34)還原為乙醇，在-1.0 V vs. RHE下，具有最高之法拉第效率(Faradaic Efficiency, FE)為35.0 %，乙醇之選擇性(Selectivity)為51.2 %。此外，CO2RR後成分變化增加催化面積，顯示其為銅鋅雙金屬異質電極。;In recent years, the rising concentration of carbon dioxide has exacerbated global warming. Therefore, converting carbon dioxide into high-value chemicals through the CO2 Electrochemical Reduction Reaction (CO2RR) can achieve the goal of carbon neutrality. This study employs Micro-Anode Guided Electroplating (MAGE) to prepare Cu-Zn alloy micro-columns and investigates the products obtained from CO2RR in 0.1 M KHCO3. The alloy micro-columns (Cu74Zn26, Cu66Zn34, Cu63Zn37, Cu55Zn45) were synthesized by setting a fixed plating bias of 4.6 V and spacing control at 40 μm while varying zinc sulfate concentration (0.15~0.18 M). The material characteristics were analyzed using SEM, EDX, and XRD. The resulting micro-columns feature a three-dimensional structure, increasing the catalytic active surface area. Subsequently, electrochemical performance was analyzed using cyclic voltammetry, linear sweep voltammetry, electrochemical impedance spectroscopy, and chronoamperometry in 0.1 M KHCO3. Results indicate that CZ16 alloy micro-column (composition Cu66Zn34) has the largest Electrochemical Surface Area (ECSA) of 8.7 cm². Additionally, at -1.0 V vs. RHE, it shows the lowest Tafel slope (for ethanol) of 185 mV/dec. Finally, GC, NMR, and FTIR were used to analyze the products post-CO2RR. Results show that CZ16 alloy micro-column (composition Cu66Zn34) reduces to ethanol, with the highest Faradaic Efficiency (FE) of 35.0 % and selectivity for ethanol at 51.2 % at -1.0 V vs. RHE. Furthermore, compositional changes after CO2RR increase the catalytic surface area, confirming it as a Cu-Zn bimetallic heterogeneous electrode. |
