【摘要】：一維納米材料的生長(zhǎng)機(jī)制研究是生長(zhǎng)控制,結(jié)構(gòu)與性能的基礎(chǔ)。螺位錯(cuò)驅(qū)動(dòng)生長(zhǎng)機(jī)制是提出于上世紀(jì)50年代,用于解釋晶體的一維生長(zhǎng),然而在有限的實(shí)驗(yàn)條件下,納米線中的螺位錯(cuò)不容易被確認(rèn)。由于實(shí)驗(yàn)技術(shù)的發(fā)展,螺位錯(cuò)驅(qū)動(dòng)生長(zhǎng)機(jī)制在2008年之后再次受到廣泛的關(guān)注。本文著重研究CuO和Zn S納米線生長(zhǎng)過(guò)程中位錯(cuò)的作用,主要內(nèi)容如下:第一,通過(guò)熱氧化法制備了CuO納米線,研究了溫度和冷卻方式對(duì)CuO納米線生長(zhǎng)的影響。600℃空冷樣品只長(zhǎng)出了少量CuO納米線,600℃爐冷樣品上觀察到了大量CuO納米線,400℃空冷樣品上也生長(zhǎng)了大量CuO納米線,表明CuO納米線的實(shí)際生長(zhǎng)溫度不高于400℃。溫度比較高時(shí),以CuO層的生長(zhǎng)為主;在溫度比較低時(shí),以CuO納米線的生長(zhǎng)為主。這一結(jié)果可以通過(guò)銅離子在氧化層中的擴(kuò)散過(guò)程來(lái)理解。第二,電子顯微結(jié)構(gòu)分析顯示,氧化銅納米線為多重孿晶結(jié)構(gòu),并發(fā)現(xiàn)納米線生長(zhǎng)方向上存在螺位錯(cuò),其螺位錯(cuò)的柏氏矢量為[110]方向。銅氧化過(guò)程的應(yīng)力和缺陷導(dǎo)致多重孿晶結(jié)構(gòu)的產(chǎn)生,多重孿晶結(jié)構(gòu)中的應(yīng)力又導(dǎo)致了納米線中的螺位錯(cuò)的產(chǎn)生,螺型位錯(cuò)推動(dòng)納米線的生長(zhǎng)。第三,在ZnS納米線中,研究發(fā)現(xiàn)層錯(cuò)導(dǎo)致生長(zhǎng)方向由[01-10]轉(zhuǎn)變?yōu)閇0001]。孿晶也能改變納米線的生長(zhǎng)方向,但不改變納米線晶體生長(zhǎng)取向。在硫化鋅納米線中存在著不全位錯(cuò),不全位錯(cuò)露頭處的臺(tái)階可以作為臺(tái)階源與螺位錯(cuò)一樣驅(qū)動(dòng)晶體的一維生長(zhǎng)。
[Abstract]:The growth mechanism of one-dimensional nanomaterials is the basis of growth control, structure and properties. The mechanism of screw dislocation driven growth was proposed in the 1950s to explain the one-dimensional growth of crystal. However, under limited experimental conditions, the screw dislocation in nanowires is not easy to be confirmed. With the development of experimental technology, the mechanism of snail dislocation driven growth has been paid more and more attention since 2008. The effect of dislocation on the growth of CuO and Zn S nanowires is studied in this paper. The main contents are as follows: firstly, CuO nanowires were prepared by thermal oxidation. The effects of temperature and cooling mode on the growth of CuO nanowires were studied. Only a small amount of CuO nanowires were grown in air-cooled samples at 600 鈩，

本文編號(hào)：2402076