隨著人類過度使用化石燃料，導致二氧化碳等溫室氣體的過度排放，造成全球氣候異常變遷。氫能汽車及氫燃料電池，因而受到主要工業國家的重視，投入大量的資金及研究人力開發。其中，氫能是否可以普遍化的主要的關鍵，便在於如何能成功地開發具有儲存足夠能源密度的材料。然而，在眾多儲氫材料中，化學儲氫被視為最佳的方式。在這些化學儲氫材料中，硼氫化鈉具有相對穩定及安全的特性，同時又擁有高理論能源儲存密度。但是，其價格昂貴，使得硼氫化鈉每單位能源的價格仍然高出石油甚多。如果要降低硼氫化鈉的價格，那麼如何成功地回收及利用使用過的硼氫化鈉的產物－偏硼酸鈉。也就是說，如何將偏硼酸鈉回收硼氫化鈉成為是主要的挑戰。
在我們的研究中，我們希望先將偏硼酸鈉轉化成為中間產物－硼酸三甲酯，再將此產物進一步反應成硼氫化鈉。目前，我們已經成功地將偏硼酸鈉反應成硼酸，這一步驟的轉化率大約為40%。接續，也已經成功地將硼酸與甲醇反應得到硼酸三甲酯。使用GC及FT-IR等儀器，顯示的確有少量的硼酸三甲酯的存在。然而，我們也發現在酯化反應中，硼酸甲酯化反應的產物－水，水的存在非常明顯地嚴重影響到硼酸三甲酯的產率。接下來使用工業濕式製程法 (Schlesinger method)將硼酸三甲酯進一步合成硼氫化鈉。經由NMR及碘滴定法分析鑑定，證實了工業濕式製程法確實可以成功得到硼氫化鈉，且產率可達約60%。
此外，我們也嚐試以高能球磨的方式，將NaBO2混合MgH2得到NaBH4，並經由NMR及XRD的定性鑑定，確定所得產物為NaBH4；經由碘滴定法進行定量分析，可知在長時間的球磨條件之下，產率可達76%，因此利用球磨的方法，確實可以一步到位地將NaBO2合成出NaBH4，而且可以得到不錯的產率。

With increasing awareness in outcomes of severe climate changes and global warming arising from excessive emission of greenhouse gases, such as carbon dioxide from excessive usage of fossil fuels, since the Industrial Revolution, urgent measures in developing alternative and renewable energies have been implemented by mankind. One strategy to amend this situation is development of hydrogen energy, such as hydrogen fuel cell and hydrogen-powered cars. However, the key to realize the hydrogen economics is the successful development of affordable hydrogen storage materials having enough energy-storage density. Among various hydrogen storage materials, chemical hydrides such as sodium borohydride are of the most promising candidates. Sodium borohydride is liquid and relatively stable at room temperature, and evolves hydrogen of high purity that could be consumed directly by subsequent fuel cell devices. Unfortunately, the cost of using sodium borohydrides based on per unit of energy is still quite expensive compared to fossil fuels. That is, cost-down of such materials is of critical importance to its successful applications.
In this project, we aim to regenerate sodium borohydride from its spent product, i.e. sodium metaborate, to reduce its cost and to ease any environmental concern on disposal of waste. Our proposal is to convert the sodium metaborate to the intermediate as trimethyl borate and, subsequently, follow the Schlesinger method to regenerate sodium borohydride. Currently, with evidence shown by GC and FT-IR, we have successfully converted sodium metaborate to trimethyl borate. However, presence of water as the byproduct in esterification of boric acid greatly reduces the yield of trimethyl borate. After that, we try to synthesize sodium borohydride via Schlesinger method. By the evidence of NMR analysis, we have successfully regenerated sodium borohydride from trimethyl borate. The corresponding yield is about 60% from the iodimetry analysis data.
On the other hand, through NMR and XRD analysis, it has been proved that sodium borohydride can be formed by ball-milling sodium metaborate with magnesium hydride at room temperature. The yields of sodium borohydride can be improved by increasing ball milling duration, and a maximum yield of 76% could be reached at present.

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