碲化铜纳米材料的液相可控合成及其电导率

doi:10.3724/SP.J.1077.2012.00433

摘要/Abstract

摘要：

采用溶剂热法在不同溶剂中(二正丙胺、丙酮和环己酮)分别制备了不同形貌的Cu₇Te₄纳米结构, 包括厚度为200 nm, 长度达几十微米的纳米带、粒径为10~25 nm的纳米粒子和由约10 nm的纳米粒子聚集构成的微米片, 并使用XRD、SEM、TEM和HRTEM等测试手段对其进行了表征. 此外, 在室温到400℃范围内测试了三种形貌样品的电导率随温度的变化曲线, 研究表明, 在相同的测试条件下, 由Cu₇Te₄纳米带制备的块体材料的电导率显著高于另外两种形貌样品. 最后, 对反应机理和三种溶剂环境对产物形貌的影响进行了探讨.

关键词: Cu₇Te₄, 纳米结构, 电导率, 反应机理

Abstract:

Cu₇Te₄ nanomaterials with different morphologies including nanobelts with the thickness of 200 nm and the length of several microns, nanoparticles with the diameter of 10-25 nm and micro-flakes consisting of nano p-ar--ticles with the size of about 10 nm were successfully synthesized using different organic solvents (N,N-Dipropyl-am-ine, acetone and cyclohexanone) by a solvothermal process. X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM) were employed to characterize the as-obtained products. Furthermore, the electrical conductivities of the samples were studied between room temperature and 400℃. The results reveal that the electrical conductivity of Cu₇Te₄ nanobelts is much higher than that of the other two samples with different morphologies. The possible mechanism and the influence of various solvents on the morphology of products are also discussed.

Key words: Cu₇Te₄, nanostructures, electrical conductivities, reaction mechanism

中图分类号:

O613

史晓睿, 王群, 吕羚源, 李洋, 俞潇, 陈刚. 碲化铜纳米材料的液相可控合成及其电导率[J]. 无机材料学报, 2012, 27(4): 433-438.

SHI Xiao-Rui, WANG Qun, LV Ling-Yuan, LI Yang, YU Xiao, CHEN Gang. Controllable Synthesis and Electrical Conductivities of Cu₇Te₄ Nanostructures[J]. Journal of Inorganic Materials, 2012, 27(4): 433-438.

图/表 6

图1 使用不同溶剂制备的Cu7Te4样品的XRD图谱 (a) N,N-Dipropylamine; (b) Acetone; (c) Cyclohexanone

Fig. 1 XRD patterns of the samples synthesized in different solvents

图2 二正丙胺作溶剂制备的Cu7Te4纳米带β(a, b)SEM照片 (c)TEM照片(d)HRTEM照片

Fig. 2 (a,b) SEM images of Cu7Te4 nanobelts, (c) TEM images and (d) typical HRTEM image of Cu7Te4 nanobelts using N,N-Dipropylamine as organic solvent the corresponding Cu7Te4 specimen

图3 丙酮作溶剂制备的Cu7Te4纳米粒子(a, b) SEM照片(c, d) TEM照片(e, f)从d图中区域Ⅰ、Ⅱ获得的HRTEM照片

Fig. 3 (a, b) FESEM images, (c, d) TEM images of Cu7Te4 nanoparticles using acetone as organic solvent, and (e, f) typical HRTEM images taken from circle zoneⅠand zoneⅡin Fig. 3(d)

图4 环己酮作溶剂制备的Cu7Te4微米片(a) SEM照片 (b) TEM照片(c, d) HRTEM照片

Fig. 4 (a) FESEM image of Cu7Te4 micro-flakes using cyclohexanone as organic solvent, (b) TEM image of an individual Cu7Te4 nanostructure, and (c, d) HRTEM images of the as-synthesized Cu7Te4 micro-flakes

图5 三种不同形貌的Cu7Te4的“电导率-温度”变化曲线

Fig. 5 Electrical conductivity for different morphologies of pure Cu7Te4 samples

图6 不同形貌的Cu7Te4生长过程示意图

Fig. 6 Schematic illustration of the proposed growth prosesses of different Cu7Te4 structures

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