發(fā)布時間：2018-07-30 08:24

【摘要】：一維納米材料(如：納米線、納米帶、納米棒和納米管)因具有優(yōu)異的光學、電學、磁學、熱學以及其他物理化學等性質(zhì)而受到科學界的廣泛關(guān)注。碲納米材料的可控制備一直是納米材料研究領(lǐng)域的難題和瓶頸。其具有很高的反應(yīng)活性,可通過簡單的化學反應(yīng)轉(zhuǎn)化為其他納米材料。如何設(shè)計簡單合理的合成方法以制備出一系列不同的一維碲納米結(jié)構(gòu),并且可以精確調(diào)控產(chǎn)物的組成成分、形貌和均一度,是有待解決的重要科學問題。本論文旨在對一維碲納米結(jié)構(gòu)的設(shè)計、合成和以一維碲納米結(jié)構(gòu)為模板合成其他納米材料的設(shè)計、合成及性能進行探索研究。通過設(shè)計不同的合成方法制備了具有不同形貌的一維碲納米材料,并以這些獨特的納米材料為模板,基于化學轉(zhuǎn)換法合成了一系列其他新穎的納米結(jié)構(gòu)。同時研究了所制備一維碲納米結(jié)構(gòu)的生長機理,發(fā)展了一種簡單、通用的控制納米結(jié)構(gòu)形貌的合成方法。進一步探究了以一維碲納米結(jié)構(gòu)為模板合成的碲化銀納米線和碳納米管的電學性質(zhì)及在能量存儲方面的應(yīng)用。取得的主要研究結(jié)果如下：1.發(fā)展了一種混合溶劑溶劑熱法,合成了具有均一形貌、尺寸的碲一維納米結(jié)構(gòu)。通過溶劑組分和反應(yīng)時間的調(diào)節(jié),實現(xiàn)了其長度和粗細的有效控制。2.發(fā)展了化學轉(zhuǎn)化法制備項鏈狀碲化銀納米線的新技術(shù)。以碲納米線為模板通過化學轉(zhuǎn)化方法,與硝酸銀反應(yīng)生成碲化銀納米線,并通過反應(yīng)溫度的調(diào)節(jié)控制碲化米銀納米線表面的粗糙程度,最終形成項鏈狀的碲化銀納米線。這種碲化銀納米線是一種相變材料,在120到145℃之間可以發(fā)生可逆相變,并引起電學性質(zhì)的變化,因此這種材料可應(yīng)用于記憶材料領(lǐng)域。3.以碲納米線為模板通過水熱碳化合成法合成了一種多功能彈性碳納米管凝膠。經(jīng)過高溫退火處理得到包含微孔、介孔和三維網(wǎng)絡(luò)結(jié)構(gòu)的多層次復(fù)雜孔道結(jié)構(gòu),這種碳納米管凝膠可應(yīng)用于制備超級電容器的電極材料和鋰離子電池的負極材料。4.將上述碳納米管和碲納米線相結(jié)合,制備了兩種基于碲的正極材料,并研制了一種無粘結(jié)劑無集流體的鋰-碲電池。碳納米管不僅起到導電和緩沖電池體積變化的作用,更重要的是借助于其多層次孔道和三維網(wǎng)狀結(jié)構(gòu)對Te和充放電過程中產(chǎn)生的多碲化鋰的強吸附作用,大大提高了電池的循環(huán)性能。這種多功能的碳納米管凝膠可以在應(yīng)用于催化、儲氫、傳感器和隔熱等領(lǐng)域。
[Abstract]:One-dimensional nanomaterials (such as nanowires, nanorods and nanotubes) have attracted wide attention due to their excellent optical, electrical, magnetic, thermal and other physical and chemical properties. The controllable preparation of tellurium nanomaterials has been a difficult problem and bottleneck in the field of nanomaterials. It is highly reactive and can be converted into other nanomaterials through simple chemical reactions. How to design a simple and reasonable synthesis method to prepare a series of different one-dimensional tellurium nanostructures and to accurately control the composition, morphology and homogeneity of the products is an important scientific problem to be solved. The purpose of this thesis is to explore the design, synthesis and properties of one-dimensional tellurium nanostructures and other nanomaterials synthesized by using one-dimensional tellurium nanostructures as templates. One-dimensional tellurium nanomaterials with different morphologies were prepared by designing different synthesis methods. A series of other novel nanostructures were synthesized by chemical conversion method using these unique nanomaterials as templates. At the same time, the growth mechanism of one-dimensional tellurium nanostructures was studied, and a simple and universal synthesis method was developed to control the morphology of the nanostructures. The electrical properties of silver telluride nanowires and carbon nanotubes synthesized from one-dimensional tellurium nanostructures and their applications in energy storage were further investigated. The main findings are as follows: 1. A mixed solvothermal method was developed to synthesize one dimensional tellurium nanostructures with uniform morphology and size. By adjusting the solvent composition and reaction time, the effective control of its length and thickness. 2. A new technique for the preparation of necklace silver telluride nanowires by chemical transformation was developed. Silver telluride nanowires were formed by chemical conversion of tellurium nanowires with silver nitrate, and the roughness of silver telluride nanowires was controlled by adjusting the reaction temperature. Finally, the necklace-like silver telluride nanowires were formed. This kind of silver telluride nanowires is a kind of phase change material, which can undergo reversible phase transition between 120 鈩，

本文編號：2154410