由於硼每單位重量熱值(13800 cal/g)遠高於許多常用燃料，適宜作為火箭吸氣式(air-breathing)燃料推進劑的重要成份。但硼的熔點與沸點分別為2450K與3931K，接觸空氣後硼外部極易形成氧化硼層，而氧化硼在常壓下的沸點高達2316K，因此在利用硼的高產熱值之前，必須先移除硼粉外側的氧化硼層，使硼顯露以進行燃燒並釋放熱能。有文獻提出可利用氟化物幫助氧化硼層的移除，尤其是LiF能與B2O3反應形成沸點較低的產物(BOF、LiBO2)，有降低硼點燃所需溫度的效果，因而發揮硼的高熱值特性。
本研究利用中和沉積法在硼粉存在下製備LiF粉末。再以XPS進行表面元素的分析，推知B與LiF粉末中元素鍵結的情形；並藉由SEM、 TGA、DSC等分析儀器探討無晶型硼粉以及B/LiF粉末在熱處理前後，重量、化學結構、形態之變化，期望能增進對此反應機制的了解。
相較於原始無晶型硼粉熱處理後重量增加一倍，LiF的存在能使B/LiF樣品熱重損失增加，而兩者物理結合的方式使得粉末顆粒的結構以及LiF含量的多寡，成為影響熱重損失效率的因素。當固定B/LiF莫耳比例為1/0.1，隨著反應物(LiOH及HF)濃度提高，LiF顆粒越小表面積越大者能提高與硼粉互相摻雜的機會，硼粉表面之B2O3與LiF接觸機會也跟著增加，有利於兩者化學反應的進行。

Due to its high gravimetric heating value (13800cal/g), boron is often used as the basic component of air-breathing propellant fuels. The melting point and boiling point of boron are 2450K and 3931K, respectively. Once contacting with air, boron can easily transform into B2O3 with high boiling point 2316K under normal pressure on the surface of boron particle. To utilize the high heating value of boron, it is necessary to remove B2O3 layer on the boron particle. It was mentioned in some literatures that fluoride can help the removal of B2O3 layer, especially LiF which can react with B2O3 and produce products (i.e. BOF, LiBO2) with low boiling point. As a result, it would be easier to ignite boron particles to liberate its high heating value.
By neutralizing precipitation method, LiF powders are prepared in the presence of boron powders. From XPS surface analysis, we can realize how the elements in B/LiF powders bonding with each other. SEM, TGA, DSC are also used to realize the differences in weight, structure and morphology between amorphous boron powders and B/LiF powders.
From the thermal analysis, unlike the weight gain of amorphous boron powders, LiF can cause weight loss for B/LiF powders. Because of the physical attachment between boron and LiF, the particle structure and the content of LiF become the crucial factors of weight loss efficiency. With the increase of reactant concentration under the same molar ratio B/LiF=1/0.1, LiF particles have smaller size and larger surface area to enhabce the efficiency contacting with boron particles. Therefore LiF can readily contact with B2O3 on the surface of boron to promote the reaction.

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