藉由電化學二氧化碳還原反應(CO2RR)，可以轉化廢氣二氧化碳作為高經
濟價值的燃料如一氧化碳，此反應已被長遠的研究並且確實可以有效地解決溫
室效應與能源短缺的問題。在這次的研究，我們合成銅核-銀殼的奈米觸媒並運
用於二氧化碳還原反應。還原劑、反應溫度與銅銀比例皆是在製程中可以提升
CO2RR 效能的關鍵變因。適當的反應溶劑需要添加三正辛基膦(TOP)以及油酸
(OA)，並在483 K 下進行。通過比例的調整，Cu2Ag1 具有最佳的產物選擇性，
電位-1.3 V 下的CO 法拉第效率為70.0%，其電流密度為-3.98 mA/cm2。根據能
量散射光譜儀(EDX)、X 光繞射分析儀(XRD)和X 光光電子光譜儀(XPS)結果，
Cu2Ag1 具有明確的核殼結構，殼層還有豐富的銀金屬態，這些被視為是影響產
物選擇性之原因。

CO2 reduction (CO2RR), which converts contaminated CO2 into potential fuel of CO, has been widely studied to better solve the problems of green-house effect and energy shortage. In our present work, CuAg bimetallic nanocatalysts have been synthesized and utilized in CO2RR application. The key synthetic parameters of reduction reagents, temperatures and Cu/Ag ratios have been thoroughly optimized to better enhance the efficiency of CO2RR. The results showed that the reagent of mixed trioctylphosphine (TOP) and oleic acid (OA), the temperature of 483 K and the ratio of Cu2Ag1 demonstrate the best CO Faradaic efficiency of 70.0% under -1.3 V (V vs. RHE), which current density of -3.98 mA/cm2. According to the characterizations from Energy Dispersive X-Ray Analysis (EDX), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), the optimized catalyst shows the appropriate core-shell structure with abundant metallic state Ag in the shell, which are responsible for the excellent CO2RR performance.

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