表面吸附对石墨烯振动性质的影响与在单分子探测中的应用

项目名称： 表面吸附对石墨烯振动性质的影响与在单分子探测中的应用

项目编号： No.11204201

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学I

项目作者： 张文星

作者单位： 太原理工大学

项目金额： 25万元

中文摘要： 石墨烯对分子吸附的极端敏感性使石墨烯在单分子探测上拥有重要应用前景，并引起了广泛的研究兴趣。以往石墨烯探测单分子是基于石墨烯的超高电导率和吸附分子后石墨烯电学性质改变的原理。利用石墨烯的超高热导率，同样可以通过振动性质的改变来探测单分子。我们使用第一性原理的方法，分别计算理想石墨烯和表面吸附了分子的石墨烯的振动性质。研究吸附分子对石墨烯振动性质的影响，并分析这些变化的物理机制。设计通过石墨烯振动性质的变化来探测单分子的器件，为单分子探测器的应用提供理论指导。使用的第一性原理计算软件有CASTEP和PWSCF。电子结构使用赝势平面波方法进行高精度计算。小原胞的声子和振动性质使用密度泛函微扰理论进行高精度计算。大原胞的振动性质使用第一性原理分子动力学进行高精度模拟与分析。计算和分析工作全部在计算服务器上完成。分析程序全部自主编写。

中文关键词： 石墨烯；吸附；单分子；振动；光谱

英文摘要： The molecule adsorption introduces a local change in electrical resistance of graphene. Due to the high electrical conductivity (even when few carriers are present) and low noise of graphene which make the change in resistance detectable, the study of graphene-based-single-molecule detection becomes very hot. In fact, due to the high thermal conductivity of graphene, changes in phonon frequency and vibrational properties (introduced by the molecule adsorption) are also detectable. We use first principle method to calculate the phonon and vibrational properties of graphene that adsorbed molecules. The changes of properties from pristine graphene to graphene adsorbed molecules are studied, and via analysing the mechanisms, a practicable graphene-based-single-molecule detection method will be suggested. First principle software CASTEP and PWSCF are used. Electronic structure is calculated by PWPP (Plane Wave and Pseudo Potential) method. Vibrational properties are studied with DFPT (Density Functional Perturbation Theory). Properties concerning to large unit cell are modeled by ab initio MD (Molecular Dynamics). All computations and analysis will be carried out by workstations and servers. Analysing programs are written by ourselves.

英文关键词： graphene；adsorption；sing molecule；vibration；spectrum