MgH2具有優越的儲氫量(7.6 wt.%)，但礙於其過於穩定的吸放氫熱力學性質及過慢的吸放氫動力學性質，使MgH2的吸放氫反應溫度偏高且反應速率過慢，因此應用上受限，而改善其缺點的方法很多，其中一種方法即為添加催化物，本研究將探討添加碳鎳複合材料(Ni/fiber)對於MgH2之放氫反應影響。碳鎳複合材料以成本便宜，操作簡易的電鍍鎳法(electroplating)將鎳顆粒披覆在聚丙烯腈(polyacrylonitrile，簡稱PAN)系碳纖維上製成，並用機械球磨法將Ni/fiber及MgH2混合成儲氫材料(MgH2+Ni/fiber)。結果顯示，以1.5V-10 min電鍍條件所製成之Ni/fiber鎳顆粒披覆效果最佳，以此Ni/fiber添加進MgH2可有效提升MgH2的放氫反應速率，其放氫所需之活化能(86.8 kJ/mol)相較於MgH2(111.3 kJ/mol)亦有明顯下降，在放氫溫度300oC及真空下，MgH2+Ni/fiber在10 min內的放氫量可達2.04 wt.%。

Magnesium hydride (MgH2) has a high hydrogen storage capacity (7.6 wt.%).However, its application is limited by high reaction temperature and slow reaction rate, which are results of stable sorption thermodynamics and slow kinetics.The kinetics can be improved by adding different catalysts or additives. In this study, we investigated the effect of carbon-supported nickel catalyst (Ni/fiber) on hydrogen desorption of MgH2.The carbon-supported nickel catalyst was prepared by electroplating of Ni particles on PAN-based carbon fiber. SEM result showed that the best coating parameter is 1.5V-10min.The Ni/fiber was then mixed with MgH2 by mechanical milling to form the Mg-based hydrogen storage material(MgH2+Ni/fiber).The results showed that Ni/fiber can improve the kinetics of MgH2 ,and that the activation energy of MgH2+Ni/fiber(85.3 kJ/mol) is lower than that of MgH2(111.3 kJ/mol).MgH2+Ni/fiber can desorb 2.04 wt.%H2 within 10 min at 300 oC.

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