本研究的主題是利用氧化鈰與氧化釔添加氧化鈰（Yttria-Doped Ceria , 簡稱YDC）來研究鎳金屬與擔體間的作用力對甲烷-二氧化碳重組反應所造成的影響。實驗為固定鎳擔載量(2wt%)，製備不同釔含量的Ni/YDC觸媒。來研究鎳金屬與氧化鈰擔體間的相互作用力對甲烷-二氧化碳重組反應的影響。
研究結果顯示金屬與擔體間的作用力會對活性金屬的分散度(Dispersion)與構型(Morphology)產生影響。因甲烷-二氧化碳重組反應乃為一種結構敏感性的反應(structure sensitivity)，反應與鎳金屬整體表面大小(ensemble size)與構型息息相關，由先前文獻上的記載與吾人實驗的結果顯示Ni – Cen+間的作用力似乎是存在的，由於強金屬-擔體作用力(簡稱SMSI)以及其他相關的效應與擔體的還原性有密切的關係，而添加氧化釔之後改變了擔體的可還原性(reducibility)進而會對金屬與擔體間的作用力產生影響並且更進一步對甲烷-二氧化碳重組反應造成顯著的影響。由程溫還原實驗的結果發現Ni/YDC觸媒會出現比整體(Bulk)氧化鎳還要低溫的還原峰，而且波峰的面積與型態(profile)會隨著氧化釔的添加量不同而有所改變。判斷造成此結果的原因和觸媒上鎳金屬構型的改變有關。而配合程溫還原與活性測試的研究結果可以推論Ni-Cen+間確有作用力存在，除此之外更可利用此種作用力的存在來製備出更具抗積碳性( coking resistivity )的觸媒。

除了金屬表面大小(ensemble size)和構型(morphology)的效應造成重組反應的高穩定性與活性外。使用Ni/CeO2觸媒更可以產生一個獨特的Ce3+離子的界面活性中心，並由於擔載在觸媒表面上的鎳金屬與鄰接的氧化鈰間會有氧遷移(Oxygen migration)的機制存在，所以使得Ce3+離子能夠於甲烷-二氧化碳重組反應的反應條件下生成與存活，藉由加速界面反應( CHxO中間體的生成與分解，並且此反應已經被廣為接受為甲烷-二氧化碳重組反應的速率決定步驟 )可加速產物的生成與積碳的移除，進而得到高活性與穩定性的觸媒。

Interaction between metal and support influence catalytic behavior apparently. To obtain insight into the effect of metal–support interaction (MSI) in the CO2 reforming of CH4, the reaction was studied using pure CeO2 and yttria-doped ceria (YDC), respectively. For comparison, Ni/γ-Al2O3 catalysts were also prepared. The catalysts were characterized by temperature-programmed reduction (TPR), electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS). For Ni/CeO2 and Ni/YDC catalysts, two TPR peak, namely β and γ, were observed. Specific rates (μ mol/(s g cat) ) for the CO2 reforming of CH4 decrease in the order Ni/CeO2 > Ni/5YDC > Ni/10YDC > Ni/20YDC > Ni/40YDC > Ni/γ-Al2O3. Ni/γ-Al2O3 showed appreciable activity for CH4–CO2 reforming. Compare to the Ni/ γ-Al2O3 catalysts Ni/CeO2 showed a dramatic increase in activity is attributed to the creation of new sites in the metal–support interaction region which promote CH4 dissociation, CO2 dissociation and reduction, and subsequent CHxO decomposition, beside activity, a dramatic stability is also fund, combination the result of temperature–programmed hydrogenation of used catalysts and temperature–programmed reduction of fresh catalysts clearly showed that the morphology of Ni on CeO2 surface consisted of very thin platelets and inhibit the rate of deep dehydrogenation of CH4 to carbon, thus improving activity maintenance.

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