Solution-based straight and branched CdTe nanowires
Solution-based straight and branched CdTe nanowires
复制标题
DOI：
10.1021/cm061559m
复制
发表时间：
2006-11-28
影响因子：
8.6
通讯作者：
Kosel, Thomas H.
中科院分区：
文献类型：
--
作者：
Kuno, Masaru;Ahmad, Omar;Kosel, Thomas H.
介绍了高质量直链和支链CdTe纳米线的合成、表征和光学性质。基于溶液的方法（溶液-液体-固体）用于通过采用低熔点纳米颗粒催化剂来诱导一维（1D）生长来合成纳米线。这利用了高质量胶体量子点（QD）开发的进展以及制造1D纳米材料的新兴技术。所得直链和支链CdTe纳米线的直径低于相应的体激子玻尔半径的两倍，因此，在其线性吸收中表现出限制效应。粒度分布范围为15%至20%，NW长度通常超过10 μ m。导丝内直径变化约为5%。高分辨率透射电子显微镜（TEM）图像显示，该线是结晶的，并只沿着< 111 >< 0001 >相应的锌钛矿和纤锌矿相的方向生长。分支NW形态包括三脚架、V形、Y形、“合并-Y”和“高阶”结构。直链和支链纳米线的初步光学研究报告，包括吸收截面和电化学带偏移的估计。这样的纳米线开辟了途径，进一步调查的大小和形状的影响的光学/电学性能的一维纳米材料，也有潜在的用途，作为有源元件的光致发光和/或偏振敏感的光电探测器。
The synthesis, characterization, and optical properties of high quality straight and branched CdTe nanowires (NWs) are described. A solution-based (solution-liquid-solid) approach is used to synthesize the NWs by employing a low melting bimetallic nanoparticle catalyst to induce one-dimensional (1D) growth. This leverages advances in the development of high quality colloidal quantum dots (QDs) with emerging techniques for manufacturing 1D nanomaterials. Resulting straight and branched CdTe NWs have diameters below twice the corresponding bulk exciton Bohr radius and, as a consequence, exhibit confinement effects in their linear absorption. Size distributions range from 15% to 20%, with NW lengths commonly exceeding 10 Am. Intrawire diameter variations are on the order of 5%. High-resolution transmission electron microscopy (TEM) images reveal that the wires are crystalline and grow exclusively along the < 111 > and < 0001 > directions of the corresponding zincblende and wurtzite phases. Branched NW morphologies include tripod, v-shape, y-shape, "merge-y", and " higher-order" structures. Preliminary optical studies of both straight and branched NWs are reported, including estimates of the absorption cross section and electrochemical band offsets. Such NWs open up avenues for further investigating the effects of size and shape on the optical/electrical properties of 1D nanomaterials and also have potential uses as active elements in photovoltaics and/or polarization sensitive photodetectors.