硫化钼层数相关的弹性及力电耦合物理力学性能研究

Physical-mechanical properties based on mechanical-electric- magnetic-thermal multifield coupling are very important to develop high-performance micro/nanoscale electromechanical devices and systems. Compared with graphene, monolayer and few-layer molybdenum disulfide (MoS2) are fasinating semiconductor materials for fabricating high-performance micro/nanoscale electromechanical devices, thickness-dependent elasticity and electromechanical coupling properties are a basis of fabricating high-performance micro/nanocale devices. However，the related theories and experiments are still scare.In this project,thickness-dependent elasticity will be measured by atomic force microscopy, where monolayer and few-layer MoS2 fabricated by chemical vapor deposition will be used,then they will be transferred onto micro/nanoscale templates with channels and holes fabricated through a nanofabrication technique. Particularly,its electromechanical coupling properties will be investigated systematically by an in-situ atomic force microscopy technique to probe the effect of mechanical strain and external electric field on electrical transport properties of MoS2. Simultaneously, by combining molecular dynamical simulation with density functional theory, physical-mechanical simulation and calculation techniques of thickness-dependent elasticity and electromechanical coupling properties will be used to investigate the influence of interlayer coupling and charge injection on elasticity and electromechanical coupling of MoS2. We will develop strain-tuning and multifield coupling physical-mechanical principles and devices by combining theories with experiments, which will provide a scientific basis and technological support for developing high-performance micro/nanoscale electromechanical devices and systems.

二维层状材料的机-电-磁-热多场耦合物理力学性能研究是发展高性能微/纳机电器件和系统的重要方向。相比石墨烯，单层及少数层硫化钼是发展微/纳机电器件极具潜力的半导体材料,与其层数相关的弹性及力电耦合物理力学性能研究是构建高性能微/纳器件的基础，但与之相关的研究还十分缺乏。本项目将利用化学气相沉积法获得硫化钼，通过微/纳制造技术构筑微/纳沟道和空洞结构模板，探索与其层数相关的弹性模量；使用原子力显微镜技术进行硫化钼原位力电耦合实验，探索机械形变、外加电场对硫化钼电输运性能的调控规律；同时将分子动力学模拟和密度泛函理论结合，发展硫化钼层数相关的弹性及力电耦合物理力学建模和计算技术，探索层间耦合、电荷注入对硫化钼弹性及力电耦合行为的影响规律。本项目通过理论与实验结合，发展出硫化钼层数相关的应变调控技术及多场耦合物理力学原理和器件，为开发高性能硫化钼微/纳机电器件和系统提供科学基础和技术支持。

二维层状材料的机-电-光-磁-热多场耦合物理力学性能研究是发展高性能微/纳机电器件和系统的重要方向。继石墨烯后，单层及少数层硫化钼成为发展微/纳机电器件更具潜力的半导体材料。本项目开展了以下几个方面的重要研究内容：1）少数层硫化钼的可控制备和转移；2）少数层硫化钼的力电耦合特性；3）少数层硫化钼的机-电-光多场耦合器件构筑和性能调控。所取得的重要结果如下：1）以钼箔为基底，在经过高温退火的钼箔表面原位生长出大面积质量可控的单层MoS2，并实现了可控转移；2）构建了单层MoS2基光电器件，结果表明该光电探测器显示出优异的光电探测性能；3）在钼箔表面上制备了垂直生长的二硫化钼薄膜，并对该薄膜进行了结构和性能表征，结果表明该类薄膜具有高效能量转换特征；4）在本项目的支持下，研究组在铜箔基底上成功制备了二维硼单层材料。所获得的关键数据及其科学意义如下: 在该项目的支持下，研究成果在Angewandte Chemie International Edition、Small、Nanoscale、Applied Physics Letters、The Journal of Physical Chemistry C、《化学进展》等国内外著名学术期刊上报道，共计发表SCI学术论文10篇。申请专利2项。培养研究生3名。少数层硫化钼材料的大面积制备和可控转移，以及机-电-光多场耦合器件构筑和性能调控研究为开发下一代高性能机-光-电-磁-热多场耦合器件奠定了良好的实验基础；二维硼单层的成功制备为硼纳米材料在光电探测器、LED、激光器、逻辑器件、高温器件及纳机电器件和系统方面的应用奠定了坚实的理论和实验基础。