本研究為了瞭解液態鋁氫化鈉於整體放氫反應中扮演之角色，首先以熱重分析儀、示差掃描量熱儀觀察鋁氫化鈉放氫溫度，並利用目視觀察與臨場同步輻射X光繞射技術確認NaAlH4(l)的存在。經臨場同步輻射X光繞射分析，可觀察到饅頭峰的現象發生，表示確實有液態鋁氫化鈉的存在，其液化溫度約為180 oC；固態鋁氫化鈉相變成液態而後發生分解之反應式成立。
接著進行低於熔點溫度的TGA持溫實驗觀察是否發生放氫反應，並透過ex-situ XRD來找出分解產物，再藉由臨場同步輻射X光繞射技術進行持溫實驗分析材料長時間低於熔點溫度過程中的結晶結構變化；評估整體放氫性質，包含放氫量、放氫溫度和反應方程式等。
經熱重分析儀分析長時間低於熔點溫度過程中持溫之鋁氫化鈉系統，其反應為固態鋁氫化鈉直接分解放氫。
透過計算固態鋁氫化鈉分解反應之活化能，可得固態鋁氫化鈉分解反應活化能為192 kJ/mole，較文獻所得之118 kJ/mole為高，推測固態鋁氫化鈉之放氫反應需於長時間下持續給予熱能使其克服活化能障礙才能發生，而液態鋁氫化鈉於此放氫反應中則扮演降低反應活化能之角色。
於鋁氫化鈉系統中分別存在兩種不同反應途徑，其反應式如下：

(1) NaAlH4(s) → NaAlH4(l)
NaAlH4(l) → 1/3Na3AlH6(s) + 2/3Al(s) + H2(g)
1/3Na3AlH6(s) → NaH(s) + 1/3Al(s) + 1/2H2(g)
(2) NaAlH4(s) → 1/3Na3AlH6(s) + 2/3Al(s) + H2(g)
1/3Na3AlH6(s) → NaH(s) + 1/3Al(s) + 1/2H2(g)

The dehydrogenation behavior of liquid phase sodium alanate was investigated by using high-pressure thermal gravimetric analysis (HPTGA) and in-situ synchrotron X-ray diffraction technique.
In-situ synchrotron XRD analysis revealed the existence of liquid phase NaAlH4, and the decomposition of NaAlH4 is followed by the phase transition reaction.
The isothermal results using TGA and XRD showed that both reactions are established. The reactions of NaAlH4 heating below melting temperature for long time will be solid state NaAlH4 decompose to Na3AlH6 and Al directly.
The dehydrogenation behavior of solid state NaAlH4 requires higher activation energy to drive the reaction. NaAlH4(l) can enhance the desorption kinetics.
The decomposition reaction of NaAlH4 can be described as following:

(1) NaAlH4(s) → NaAlH4(l)
NaAlH4(l) → 1/3Na3AlH6(s) + 2/3Al(s) + H2(g)
1/3Na3AlH6(s) → NaH(s) + 1/3Al(s) + 1/2H2(g)
(2) NaAlH4(s) → 1/3Na3AlH6(s) + 2/3Al(s) + H2(g)
1/3Na3AlH6(s) → NaH(s) + 1/3Al(s) + 1/2H2(g)

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