本研究以硬脂酸與異硬脂酸合成溶於有機溶劑中之金屬前驅物，以氫氣還原後，即可得分散於有機溶劑中之奈米級金屬粒子。鈀金屬奈米粒子的型態受金屬保護基結構的影響，以直鏈結構之硬脂酸做為保護基，可得三角形的奈米粒子，以多支鏈的異硬脂酸為保護基，奈米粒子則呈現長條狀。此兩種金屬前驅物於二氧化碳膨脹溶液(CO2-expanded liquid, CXL)中進行還原，皆可得球型的鈀金屬奈米粒子，同時可得到較小得鈀金屬奈米粒子粒徑與較窄的粒徑分布。
鈀金屬奈米粒子之活性受到奈米粒子型態的影響，球型奈米粒子之活性最好，其次是三角形奈米粒子，活性最差的是長條形奈米粒子。將此法合成之鈀金屬奈米粒子應用於氫化反應時，可將還原與氫化程序結合為單一步驟進行反應，其活性優於商用觸媒Pd/C與商用金屬前驅物(醋酸鈀與乙醯丙酮鈀)。
於二氧化碳膨脹液體中，亦可合成粒徑約為 3 nm之鈀銀雙金屬奈米粒子，這些粒子具有相當優良的分散性。經由鑑定證實鈀銀雙金屬奈米粒子結構為合金型奈米粒子且其組成具有可調整性。鈀銀雙金屬奈米粒子之粒徑與分散性與氫氣添加量及還原溫度有關，最佳的合成條件為還原氣體氫氣與二氧化碳之壓力分別為200 psi與600 psi，以及40 oC下還原60 min，可得粒徑為2.9 ± 0.7 nm之鈀銀雙金屬奈米粒子。
以鈀銀雙金屬奈米粒子進行Phenylacetylene氫化反應時，加入二氧化碳可提高Styrene選擇率，當以Pd0.3Ag0.7為觸媒時，二氧化碳添加量為20%，於40 oC下反應30 min，轉化率可達100%，Styrene選擇率為91.8%。

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