本論文探討有機金屬化學氣相沉積垂直立於基材的氧化釕奈米桿(RuO2)陣列，經還原後為Ru/RuO2、(Ru,RuO2)及Ru奈米桿，電鍍Pt於Ru/RuO2、(Ru,RuO2)及Ru奈米桿製備成Pt/Ru/RuO2、Pt/(Ru,RuO2)及Pt/Ru觸媒，測試其氧化有機小分子的催化活性。
藉由SEM、XRD、XPS及拉曼光譜，可知氧化釕奈米桿於還原前後的結構、形貌及成分變化。利用循環伏安法測試Ru/RuO2、(Ru, RuO2)及Ru奈米桿與Pt/Ru/RuO2、Pt/(Ru,RuO2)及Pt/Ru在電化學觸媒上的特性，可知經還原後的奈米桿其電化學觸媒活性增加。此外，經還原的奈米桿在-0.2V∼0.9V(vs. Ag/AgCl)以循環伏安掃流多圈後，有Ru金屬溶解現象，此現象普遍存在於所有包含Ru金屬的電化學觸媒(PtRu)中。
討論Pt/Ru/RuO2、Pt/(Ru,RuO2)及Pt/Ru觸媒對甲醇、乙醇、甲酸、乙二醇與甲醯胺的氧化測試，並進一步瞭解其抗CO毒化作用。其中Pt/Ru(7.6nm)對甲醇氧化，在0.48V∼0.85V(vs. Ag/AgCl)較JM PtRu高出許多，但Ru的掃流上限電位至0.7V(vs. NHE)以上時，屬不可逆氧化還原反應，代表Ru會溶解，因此Pt/Ru(7.6nm)真正優勢約在0.48V∼0.5V(vs. Ag/AgCl)，且其CO氧化峰電位為0.286V(vs. Ag/AgCl)(掃流速率10mV/s)，與文獻值相當，表示其抗CO毒化效果佳。此外，Pt電鍍於還原後較小的釕晶粒尺寸上，對於氧化甲醇有很明顯的正面影響。

關鍵字：氧化釕奈米桿、電化學觸媒、抗CO毒化

We have explored the catalytic activities of Pt/Ru/RuO2, Pt/(Ru,RuO2), Pt/Ru derived from RuO2 nanorods in electrochemical oxidation of small organic molecules. The electrocatalyts were prepared by electrodepositing Pt on the Ru/RuO2, (Ru,RuO2), Ru nanorods array which were reduced from RuO2 vertical rods array grown in metalorganic chemical vapor deposition. The structure , morphology and composition of RuO2 nanorods before and after reduction were investigated by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy. The variation in electrocatalytic properties is studied by cyclic voltammetry. After reduction, the catalytic activity of Ru/RuO2, (Ru,RuO2), Ru nanorods was enhanced. However, the Ru metal dissolves in sulfuric acid during repetitive cycling in scanning voltage range -0.2V∼0.9V(vs. Ag/AgCl). The Ru dissolution is a problem common to all electrocatalysts containing PtRu.
The catalytic activity of Pt/Ru/RuO2, Pt/(Ru,RuO2), Pt/Ru is studied in CO stripping and cyclic voltammetry using methanol, ethanol, formic acid, ethylene glycol, formamide. Various factors in catalytic activity have been extensively studied. In methanol oxidation reaction, the best electrocatalyst is Pt/Ru(7.6nm) which exhibits a higher oxidation current density than the JM PtRu HiSPEC 6000 in the voltage range 0.48V∼0.85V(vs. Ag/AgCl). But Ru will dissolve over 0.50V(vs. Ag/AgCl). So Pt/Ru(7.6nm) is better than JM PtRu HiSPEC 6000 in the voltage range 0.48V∼0.50V(vs. Ag/AgCl). In the CO stripping, CO stripping peak potential of Pt/Ru(7.6nm) is 0.286V(vs. Ag/AgCl) using sweep rate 10mV/s. It’s value is as low as others experimental data, so Pt/Ru(7.6nm) has good tolerance for CO.
Besides, Pt of electroplating on smaller Ru grain size by reducing RuO2NR has excellence at oxiding methanol.
Keywords: RuO2 nanorods, electrocatalysts, CO tolerance

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