硅纳米管及化学修饰和缺陷结构电子输运性能的密度泛函研究

项目名称： 硅纳米管及化学修饰和缺陷结构电子输运性能的密度泛函研究

项目编号： No.21203020

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理化学

项目作者： 张珉

作者单位： 东北师范大学

项目金额： 22万元

中文摘要： 本项目以硅纳米管为研究目标,利用密度泛函理论借助Laudauer-Buttiker散射波函数和非本征态格林函数方法等探讨硅管的电子输运性质及其输运机理。采用两个半无限电极与硅管相连构成纳米尺度的开放系统(器件)的模型等，将量子输运性质的研究与计算硅管的电子结构相结合，并在电极上引入偏压以获得纳米硅管开放体系的电流-电压性质、态密度、激发光谱等。并通过对具有重要贡献的分子轨道和Bloch态、分子振动模式、电子密度、散射态等分析获得决定输运性质的重要因素。 研究以具有代表性的不同手性和直径的sp2和sp3杂化的硅管为基本结构，获得具有优秀输运潜质的单壁硅管结构。在所获得的结构基础上，模拟常见化学修饰、缺陷程度和多种掺杂条件等因素对传输性质的影响，从而详细阐述实际应用中硅纳米管作为电子输运材料的价值。同时开展嵌套的多壁sp2杂化硅管结构、硅纳米线及其中心缺陷后形成的硅管结构的电子输运性质。

中文关键词： 硅纳米管；硅石墨烯；电子输运；纳米分子器件；化学键本质

英文摘要： Silicon nanotubes(SiNTs) are the main research goal in this project. The electron transport capability and mechanism in SiNTs are investigated using density functional theory with Laudauer-Buttiker scattering wave and non-equilibrium Green function. Two semi-infinite electrodes and the silicon tube connected to constitute nanoscale open systems(devices), and then bias-voltage is introduced on the electrodes. By this method, the relationship between quantum transport properties and electronic structures of SiNTs can be achieved. With the help of bias-voltage, we simulate current-voltage character, density of states, electron excitation spectra of SiTNs and so on. The main contribution factors in determining transport properties of SiNTs will be discovered, by analysing molecular orbitals, Bloch States, molecular vibrational modes, electron density, scattering state and so on. The electron transport property of single-walled silicon nanotubes (SWSiNTs), with representive sp2- and sp3-hybridized structures in different chirality and diameter, will be studied first to exploring the potential candidate basic structures. Many other common conditions, such as chemical modifications in the structure, defect and topology structures, doping effects by p-/n-type and transition metals with different spin states, will be si

英文关键词： Silicene nanoribbon；Silicon nanotube；Electron transport；nanoscale device；the nature of chemical bond