氧化石墨烯片层变形行为及其机制的分子动力学模拟研究

项目名称： 氧化石墨烯片层变形行为及其机制的分子动力学模拟研究

项目编号： No.51501012

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 一般工业技术

项目作者： 孙运金

作者单位： 北京农学院

项目金额： 20万元

中文摘要： 作为石墨烯的重要衍生物之一，氧化石墨烯既能与聚合物复合增强聚合物的力学强度，也能与多种基体复合实现新的功能特性，近年来引起国际学术界的高度关注。氧化石墨烯的出现一方面赋予石墨烯良好的可加工性，另一方面继承了石墨烯的优良特性，从而大大拓展了石墨烯的应用范围。然而，由于氧化石墨烯表面吸附官能团的sp3杂化特征，其力学强度大幅降低且变形过程容易发生应力集中，成为石墨烯基器件应用亟待解决的关键问题。本项目拟基于分子动力学模拟方法系统研究吸附不同类型官能团的氧化石墨烯片层的稳定构型；通过对拉伸加载过程的模拟研究揭示氧化石墨烯片层的基本变形行为；通过调整氧化石墨烯片层的特征尺寸和纵横比，适当引入局域缺陷，改变加载的温度和应变速率条件来考察并明确其变形的基本特征、微观结构变形机制及影响因素, 从而为相关复合材料强韧化机制和可靠性设计提供材料学基础理论支撑。

中文关键词： 变形行为；氧化石墨烯片层；分子动力学模拟；力学性能

英文摘要： As one of important graphene derivatives, graphene oxide (GO) could combine with both polymers to enhance the mechanical strength of matrix and many kinds of substrates to form some special function materials, which has been attracting extensive research interests in recent years. The rise of GO not endows graphene good machinability but also inherits the excellent properties of graphene, thus greatly expanding the application scope of graphene. However,due to sp3 hybridization feature of absorbed groups in the surface, the mechanical strength of GO significantly decreases and stress concentration always occurs during deformation process, which becomes the key problems in the applications of graphene based devices to be solved. Based on the molecular dynamics simulation method, this project will systematically investigate the structural stability of GO sheet absorbing different kinds of functional groups; reveal the basic deformation behaviors by simulating and investigating tensile loading process; observe and study the basic characteristics of deformation, micro structural deformation mechanism and influence factors by adjusting feature size and length to width ratios, appropriately introducing local defects, changing loading temperature and strain rate, with the aim of providing theoretical support of strengthening-toughening mechanism and reliable design of related compound material from the respect of the basic theory of materials science.

英文关键词： Deformation Behaviors;Graphene Oxide Sheet;Molecular Dynamics Simulation;Mechanical Properties