現今認為儲氫合金具有高度發展之潛力，其原理是將氫氣以物理或化學吸附的方式儲存於合金當中，氫化鎂的理論儲氫值高(7.6wt.%)且價格低廉，但放氫溫度高且吸放氫動力學性差，研究發現添加過渡元素能改善性質。本實驗添加氫化鈦與鈀，探討其對氫化鎂儲氫性質的影響。
本文研究方法包含實驗與量子力學模擬兩大部分，實驗部分使用氫化鎂作為主材料，分別添加 與 球磨形成下列材料： 、 、 ，以TGA/DSC與PCT量測其吸放氫量、吸放氫時間和吸放氫溫度，並以SEM跟XRD做材料結構與化合物成份分析。模擬的部分，由量子力學角度出發，借密度泛函理論與第一原理，計算材料表面在摻雜催化劑元素後，其態密度與穩定性的改變。
由實驗結果可以歸類出下列結論：(1)由於 本身具有對氫的高親和力，又從XRD中可發現 的存在，此說明 亦有幫助 脫氫的作用，因此 具有三者間最高的儲氫量(5.5wt.%)。(2)對 做XRD分析後可發現，並沒有新的 相關化合物產生，故認為 僅為催化劑，由 與 的吸放氫循環圖可以知道其能幫助 在低溫情況下吸氫。(3) 與 具有偕同作用，由XRD可以發現兩者生成 和 等化合物，比較三樣材料之吸放氫循環圖後，可以發現 具有最低的放氫溫度，因此認為 - 的偕同作用能有效降低放氫溫度。(4)由於溫度越高，分子的動能則越高，故吸氫時間大致會隨著溫度升高而縮短，但又吸氫反應本身為放熱反應，過高的溫度反而不利於反應進行。(5)活化亦為儲氫中重要一環，由SEM中可以發現，經活化的材料其尺寸會縮小而表面破碎且面積增加，使得吸放氫過程加快。(6) 和 雖使放氫溫度下降，但也需更大環境壓力方能吸氫，故其平台壓略大於其他材料。(7)量測不同溫度下 之PCT曲線，可繪製出Van’t Hoff關係圖，並得到其解離熵與解離焓分別為83 KJ‧mol-1與135.8 J‧mol-1。
此外，模擬的部分，可得以下幾點結論：(1)添加Pd/Ti會使Mg-H鍵長分別增加1.3%與18%。(2)由 之總/分波態密度圖可發現，價帶區域與導帶區域中存在一寬能隙，寬度約4.0eV。(3)由 - 之總/分波態密度圖顯示，摻雜的 原子在+0.2eV處與Mg、H發生雜化，使導帶底部由費米能級EF右方移至左方。(4)由 - 之總/分波態密度圖中，發現其PDOS峰值往左偏移，但峰型沒有改變，表示 並未對 的電子組態造成太多影響或形成新鍵。(5) -d軌域所提供的電子使能隙消失，價電子移動至導帶所需要之能量下降，其放氫溫度隨之下降。(6)模擬顯示摻雜催化原子的晶體解離能下降，同時放氫溫度下降。

Nowadays, the great majority believe that there is great potentiality in hydrogen storage alloy storing hydrogen by physical and chemical absorption. MgH2 has high capacity and unexpansive. However, its operation temperature is high and owns poor kinetics. Currently, scientists find that adding transition elements can improve the properties of hydrogen storage alloy. In this research, outstanding improvements of kinetic and thermal properties are given by addition of Palladium and Titanium hydride to Magnesium-based alloy.
The research involves experiment and quantum-mechanical calculation. In experiment, magnesium-based alloy is used as main material, into which TiH2/Pd are added separately. TGA/DSC and PCT measure the capacity, spending time and temperature of abs/des-orption, additionally, SEM and XRD analyze the structures and components of material. The quantum mechanical calculation is based on Density Function Theory and the First Principle. The changes of DOS and stability are observed after doping.
The results of the real experiment clearly demonstrate following points. (1) Because Pd owns highly affinity to hydrogen and Mg6Pd was found from the XRD, it is clearly shown that Pd is beneficial of dehydrogenation. 2MgH2-0.1Pd has the highest capacity of all the alloys listed, approximately 5.5 wt.%. (2) From XRD analysis, it could not find any new Ti-related compound. Thus, TiH2, considered as the catalyst, leads to the condition of 2MgH2-TiH2 and 2MgH2-TiH2-0.1Pd efficiently absorbing hydrogen in low temperature. (3) Due to the synergistic effects between Pd and TiH2 (PdTi2 and Pd2Ti are produced by mechanical alloying), 2MgH2-TiH2-0.1Pd owns the lowest dehydrogenation temperature. (4) The higher temperature is; the stronger kinetic energy molecule has. Generally, the time spending on absorption would decrease as the temperature raise. However, too high temperature is unbeneficial to reaction since the absorption reaction is exothermic. (5) Activation plays an important role in the abs/des-orption. It shortens the abs/des-orption time because of the surface area increasing. From SEM, it is clear that the size and surface become smaller and rougher. (6) Even though PdTi2 and Pd3Ti decrease the limited dehydrogenation temperature, they need more pressure to react. Therefore, the plateau of 2MgH2-TiH2-0.1Pd is slightly higher than others. (7) According to the PCT curves of 2MgH2-TiH2-0.1Pd at the different temperature, Van’t Hoff related plot can be described. 2MgH2-TiH2-0.1Pd’s enthalpy (83 KJ‧mol-1) and entropy (135.8 J‧mol-1 ) are given by Van’t Hoff related plot.
Furthermore, in simulation part, there are also some points: (1) adding Pd/Ti would increase distance of Mg-H. (2) From MgH2’s T/PDOSs, there is an gap between the valence band and conduction band, roughly 4.0eV. (3) From MgH2-Pd’s T/PDOSs, there is a spd hybridization between Pd, Mg and H atom at +0.2eV. It moved the bottom of the conduction band below Fermi energy. (4) Because the peak of MgH2-Ti’s PDOSs’ do not alter much but slightly move, Ti is believed as the catalyst. (5) Energy Gap is vanished by the electrons provided by Ti-d. It means the temperature and energy of dehydrogenation decreasing. (6) The dehydrogenation energy decreases while doping catalytic elements and temperature falls simultaneously.

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