- 學位論文
爆炸法合成奈米鑽石之研究
The Study of the Synthesis of Nanodiamond with Detonation Method
摘要
本文針對爆炸法合成奈米鑽石，以 TNT / RDX為50︰50之比例，控制不同冷卻介質(氮氣、氮氣 + 水、氮氣 + 冰塊)條件下引爆，由炸藥在負氧平衡(negative oxygen balance)環境爆炸生成，在瞬間（10-6 秒）及高壓( 20 ~ 30 GPa)�高溫 ( 3000 ~ 4000 K)下成長。探討反應條件對產率之影響，由結果顯示，奈米鑽石產率分別為4.8 %、7.2 %及7.8 %。因此，於氮氣 + 冰塊之爆炸條件下，可得到最高產率，進一步顯示快速降溫對形成鑽石為重要條件。由產物之 XRD 圖譜，顯示 2θ = 44°、75°、91.5°之繞射峰分別為鑽石 (111)、(220)、(311) 晶格面吸收峰。產物以元素分析 ( EDS ) 結果，顯示碳含量為 89.52 %、氧為 10.48 %。由 FT-IR 傅立葉紅外光譜鑑定，得知所合成的奈米鑽石表面仍有少數之含氧基團位於3435 及 1637 cm-1等處；以拉曼光譜鑑定，奈米鑽石出現 D-band 之吸收峰位於1300 ~ 1400 cm-1間。藉由 Zeta potential 分析儀之鑑定，發現奈米鑽石於油酸鈉 ( Sodium Oleate )分散劑存在下，若於鹼性條件 ( pH = 8 ~ 10)，界面電位值於負40 ~ 50 間為最低值，表示此時可使奈米鑽石有最佳之分散效果，且測得之粒徑大小為 40 ~ 60 nm。經 ESCA作鍵結能測試分析，鑽石相比例約為 60 %，推算密度為 3.2 g/cm3之間。經表面積氣體吸附測試儀 (BET) 測試，樣品比表面積為 337.09 m2/g。產物經 13C 固態核磁共振作光譜分析，確認於 35±2 ppm 處有 SP3 鍵結之吸收峰。經相關鑑定後，經以上物性鑑定後，確定試樣中有奈米鑽石之存在。
並列摘要
The detonation decomposition of powerful mixed explosives (TNT & RDX) with a negative oxygen balance for the formation of nanodiamond (ultrafine-dispersed diamond, UDD) has been studied. The pathway of formation in phase diagram of diamond during the detonation process was controlled and compared with different cooling agents. In this research, the explosive results were examined in the high pressure stainless chamber with 10 L volume and wall thick in 10 mm. The detonation of mixture for 5 g TNT and 5 g RDX was ignited by electric detonator. Using the optimum explosive condition, the yield for the formation of nanodiamond powder could be reached about 7.8 % by the explosive detonation method. Furthermore, we have developed the technologies for the isolation and purification of nanodiamond from the residue of explosion. The synthesized product has been found in nano-scale size with 4 – 6 nm that was confirmed by TEM test. For characterizing physical properties of the synthesized nanodiamond, several tests have also further been examined including EDS, XRD, TEM test, FT-IR, Raman test, Zeta potential analyzer, BET test, ESCA test, 13C-NMR.