本文選題：碳納米材料 + 分子篩�。� 參考：《太原理工大學(xué)》2010年博士論文

【摘要】：碳納米管(Carbon nanotubes:CNTs)和洋蔥狀富勒烯(Onion-like fullerenes:NOLFs)等碳納米材料自發(fā)現(xiàn)以來,以獨特的結(jié)構(gòu)和電學(xué)、磁學(xué)、力學(xué)、化學(xué)等特殊的性能,開辟了新的科學(xué)研究領(lǐng)域,在工程、電子、信息、能源、生物醫(yī)藥、化工和國防等領(lǐng)域具有潛在的應(yīng)用前景。 本論文首先以簡單的路徑合成Li-ABW沸石分子篩,并采用傳統(tǒng)的水熱法以及非常規(guī)極濃體系、蒸汽相條件下分別合成MCM-41；然后在此模板上負載Fe做催化劑,采用化學(xué)氣相沉積(Chemical Vapor Deposition,CVD)法合成了CNTs。另外,提出了由“聚合預(yù)成形+熱處理成形”兩步反應(yīng)模板法合成NOLFs;并利用金剛石對頂砧實驗技術(shù)(Diamond Anvil Cell,DAC)系統(tǒng)研究了NOLFs的高壓性能。 研究的主要內(nèi)容和結(jié)果如下： 1.分子篩合成 1)Li-ABW模板劑的合成 比較了相同晶化溫度(150℃)、不同Li/Si摩爾比條件下合成沸石Li-ABW(Li/Si=1.5)和混合相Li-ABW+Li2SiO3(Li/Si=2.5)的晶體結(jié)構(gòu)、焙燒相轉(zhuǎn)變過程以及表觀形貌等。結(jié)果表明：沸石Li-ABW可以在150℃的較低溫度下用硅溶膠和異丙醇鋁作原材料直接合成,其合成的最佳條件為：摩爾組成1.5Li2O：Al2O3：2SiO2：154H2O,150℃下晶化7天；當Li/Si摩爾比為2.5時,沸石從ABW純相向ABW+Li2SiO3混合相轉(zhuǎn)變。 2)MCM-41模板劑的合成 在M20(M=Li,Na,K)-Al2O3-SiO2-CTAB-H2O水熱凝膠體系中,合成介孔(1.5-4nm)MCM-41分子篩。相對結(jié)晶速度為：K-MCM-41Na-MCM-41 Li-MCM-41.實驗表明：K-MCM-41分子篩的晶體結(jié)構(gòu)、吸附特性及熱穩(wěn)定性接近或優(yōu)于Na-MCM-41分子篩. 在NaX-Na2O-A12O3-SiO2-CTAB-H20水熱體系中合成MCM-41分子篩。實驗表明：F-引入可加速MCM-41分子篩晶化速度；大量引入Br-影響MCM-41分子篩晶化。 在含輔助烷烴(正己烷、正庚烷、異辛烷)的水熱體系中合成d100較大的MCM-41分子篩,d100值隨輔助烴的碳數(shù)增加而增大。石油醚具有與前述烷烴類似的作用。水熱體系中加入輔助烷烴使MCM-41分子篩的有序性降低,比表面積、孔體積略有減小。 在極濃體系中,由無定形凝膠Na2O-SiO2-CTAB-H2O合成MCM-41分子篩。CTAB/Si降至0.0125可以合成MCM-41分子篩,能有效地減少合成中CTAB的消耗。 用蒸氣相法可以合成Si-MCM-41和Al-Si-MCM-41分子篩的純相；蒸氣相法可以明顯地減少MCM-41分子篩制備過程中表面活性劑CTAB的消耗量；含有適量鋁的樣品比純硅樣品具有較高的熱穩(wěn)定性。 2.通過浸漬法制備了Fe/ABW.Fe/MCM-41和Fe/SBA-15分子篩催化劑,以其為模板,乙炔為碳源,Ar為保護氣采用CVD法,考察了不同溫度(600,700,800℃)、反應(yīng)區(qū)域和分子篩載體對合成納米碳材料的影響,另外,還考察了未負載任何催化劑的分子篩合成納米碳材料以及實驗中催化劑未經(jīng)氫氣還原合成納米碳材料的結(jié)果。結(jié)果表明：在反應(yīng)溫度為700℃,三種不同的催化劑經(jīng)H2還原后,在反應(yīng)溫度區(qū)催化生長出直徑均勻(20-30nm)且晶化程度較好的CNTs. 3.模板法是一種具有創(chuàng)新性的制備NOLFs的方法,是以苯乙烯和丙烯酸等有機物單體為碳源,通過單體間的聚合反應(yīng)使納米金屬顆粒包裹在內(nèi),形成內(nèi)包金屬NOLFs的前驅(qū)體；然后采用熱處理方法將其轉(zhuǎn)變?yōu)槭潭雀叩腘OLFs,其核心為直徑約60nm的鐵納米顆粒。通過場發(fā)射掃描電子顯微鏡和高分辨透射電子顯微鏡觀察分析,結(jié)果表明：模板法制備NOLFs是一種十分新穎有效的制備方法,通過聚合反應(yīng)和熱處理成形這兩步制備NOLFs,使NOLFs的形貌和大小具有高度可控的特點,對NOLFs的性能和應(yīng)用研究非常重要。 4.采用電弧放電技術(shù)在液體中合成了高純度的NOLFs和內(nèi)包金屬的NOLFs,并利用DAC對其高壓Raman光譜進行了研究。結(jié)果表明,NOLFs的壓力系數(shù)和彈性行為與多壁碳納米管非常相似,且在20GPa高壓下,沒有發(fā)現(xiàn)同心石墨殼層結(jié)構(gòu)的塌陷,說明NOLFs的硬度非常高,能夠承受很大的壓力。但DAC實驗加壓前后ID/IG比值的顯著變化卻從另一個側(cè)面證明,盡管加壓前后石墨殼層骨架結(jié)構(gòu)沒有發(fā)生塌陷,但還是存在諸如石墨層和金屬核之間相界面結(jié)構(gòu)的一定程度的結(jié)構(gòu)破壞。
[Abstract]:Carbon nanotubes ( CNTs ) and onion - like fullerene ( NOLFs ) have developed new scientific research fields with unique structure and electrical , magnetic , mechanical and chemical properties , and have potential application prospects in the fields of engineering , electronics , information , energy , biological medicine , chemical engineering and national defense .

In this paper , the Li - ABW zeolite molecular sieve was synthesized by a simple path , and MCM - 41 was synthesized under the condition of vapor phase by using conventional hydrothermal method and unconventional polar concentration system .
In addition , the high voltage performance of NOLFs was studied by means of diamond Anvil Cell ( DAC ) system .

The main contents and results of the study are as follows :

1 . Molecular sieve synthesis

1 ) Synthesis of Li - ABW Template Agent

The crystal structure of Li - ABW ( Li / Si = 1.5 ) and Li - ABW + Li2SiO3 ( Li / Si = 2.5 ) were synthesized from Li - ABW ( Li / Si = 1.5 ) and Li - ABW + Li2SiO3 ( Li / Si = 2.5 ) at the same crystallization temperature ( 150.degree . C . ) .
When the molar ratio of Li / Si was 2.5 , the zeolite was transformed from ABW pure opposite ABW + Li2SiO3 .

2 ) Synthesis of MCM - 41 Template Agent

The mesoporous ( 1.5 -4 nm ) MCM - 41 molecular sieve was synthesized in the hydrothermal gel system ( M = Li , Na , K ) - Al2O3 - SiO2 - CTAB - H2O . The relative crystallization velocity was : K - MCM - 41 Na - MCM - 41 Li - MCM - 41 . The experimental results show that the crystal structure , adsorption characteristics and thermal stability of K - MCM - 41 molecular sieve are close to or better than those of Na - MCM - 41 molecular sieve .

The MCM - 41 molecular sieve was synthesized in hydrothermal system of NaX - Na2O - Al2O3 - SiO2 - CTAB - H2O .
Large amounts of Br - affect the crystallization of MCM - 41 molecular sieve .

In the hydrothermal system containing auxiliary alkane ( n - hexane , n - heptane and isooctane ) d100 , the d100 was synthesized and the d100 value increased with the increase of the carbon number of the auxiliary hydrocarbon . The petroleum ether has the similar effect as the above - mentioned alkane . The addition of the auxiliary alkane to the hydrothermal system decreases the ordering of MCM - 41 molecular sieve , the specific surface area and the pore volume decrease slightly .

The MCM - 41 molecular sieve was synthesized from amorphous gel Na _ 2O - SiO _ 2 - CTAB - H2O by amorphous gel Na _ 2O - SiO _ 2 - CTAB - H2O . The MCM - 41 molecular sieve could be synthesized by reducing CTAB / Si to 0.0125 , which could reduce the consumption of CTAB .

The pure phase of Si - MCM - 41 and Al - Si - MCM - 41 molecular sieve can be synthesized by vapor phase method .
the vapor phase method can obviously reduce the consumption of surfactant CTAB during the preparation of MCM - 41 molecular sieve ;
Samples containing an appropriate amount of aluminum have higher thermal stability than pure silicon samples .

2 . Fe / ABW . Fe / MCM - 41 and Fe / SBA - 15 molecular sieve catalysts were prepared by impregnation . The effects of different temperatures ( 600 , 700 , 800 鈩，

本文編號：2051798