氫能為未來替代能源的方案之一，目前工業上大部分氫氣的來源仍來自於甲烷蒸汽重組反應(SRM)，這是由於甲烷具有高氫碳比例(H/C=4)，一般工業上SRM操作溫度約700~900℃，但高溫環境下操作會增加能源的耗損與危險性。因此，中溫(400~600℃)甲烷蒸汽重具有發展潛力。本研究探討一系列不同比例混合氧化物(La2O3-ZrO2-CeO2) 擔載Ni觸媒，結果顯示Ce的含量明顯提升Ni觸媒低溫(≦500℃)催化活性及穩定性，其中最佳比例La:Zr:Ce =1:1:1 (mole)的Ni觸媒在400~600℃可有效催化SRM，在WHSV=2h-1條件下達到平衡轉化率，並在500℃能穩定催化反應24小時無失活現象發生，有接近理論H2產率(約4)的高H2產率及低CO選擇率(約5%)。此外，TGA與XRD分析結果顯示Ni/LZC觸媒在500℃ 24小時反應後並無積碳生成或Ni顆粒金屬團聚現象發生，值得注意的是高Ni含量(40wt%)情況下XRD分析Ni金屬顆粒大小約為10 nm，EXAFS分析Ni金屬配位數約為6，顯示Ni金屬具有良好的分散性，此結果可能來自於Ni金屬與LZC載體具有良好作用力。

Hydrogen is a possible choice for future energy supplies. Hydrogen mainly comes from the steam reforming of methane (SRM), which contains a high ratio of H/C = 4. Industrial SRM operating temperature is around 700~900℃, but high temperature increase energy consumption and process stability. Therefore, the SRM at mid-temperatures (400–600°C) is examined in this study. A series of La2O3-ZrO2-CeO2-mixed oxide is studied as the support for Ni catalysts. Increase in CeO2 content results in increased activity and stability at ≦500℃. The prepared Ni/LZC, with La:Zr:Ce = 1:1:1 (mole), catalysts readily catalyzed SRM and can reach equilibrium conversion starting from 400°C at WHSV = 2 h-1. The best-performed Ni/LZC provides high H2 yield of around 4 and low CO selectivity of less than 5% and the catalyst shows no activity loss during SRM at 500°C for 24 hours. TGA demonstrate that carbon deposition is significantly suppressed on this catalyst. Moreover, XRD results show Ni particle size of around 10 nm when Ni content is as high as 40% and no particle agglomeration is observed after 24-h reaction test at 500°C. EXAFS analyses show a coordination number of Ni metal of around 6, which shows high Ni metal dispersion probably by enhance the interactions between Ni and the support.

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