超弹性高性能摩擦电发电机输出机理及界面摩擦行为研究

The triboelectric generator which uses the coupling between contact triboelectricfication and electrostatic induction provides a novel type for harvesting ambient mechanical energy and converting it into electric energy. It has broad application prospects due to its unique properties such as low cost, high efficiency and easy to carry. . This proposal aims to solve the two key problems in the triboelectric generator research, which are the low charge density on the polymer surface and the unrevealed tribologicl performance at the contact interface under coupling effect by the combination of theoretical and experimental research. A superelastic material is employed on the basis of the research of the influencing factors of output performance. A series of problems as the surface charge distribution, the adhesion mechanism, the contact fatigue and tribological performance of the superelastic material under electrostatic-force coupling field are studied. The charge transfer and aggregation mechanism are obtained on the sharply reduced surface area. The high power output method and theory together with the mathematical model between the contact area and the electrical output performance for the triboelectric generator are established. The relation of pressure-elastic deformations response, the contact fatigue failure and its regulation mechanism for the superelastic material are revealed. The tribological rules of the soft elastic material in dry friction conditions under the electrostatic-force coupling effect are founded and finally, an empirical formula that can evaluate both tribological performance and output performance for the soft elastic polymer based triboelectric generator is constructed. . The obtained conclusions lay the foundation for the design of long life, high power triboelectric generator and will also provide a theoretical support for the designing and manufacturing of the soft machine.

基于接触生电与静电感应原理的摩擦电发电机作为一种低成本、高转化效率、易携带的发电装置，具有广阔的应用前景。本课题针对目前摩擦电发电机中聚合物表面电荷密度低及接触界面耦合摩擦学规律不明这两个关键基础问题，采用理论与实验研究相结合的方法，在对摩擦电发电机电输出机理研究的基础上引入超弹性体材料；通过对超弹性体材料表面在力电耦合场下的电荷分布、粘附机制、接触疲劳及摩擦学行为研究，探明静电荷在超弹性体材料表面积急剧变化时的转移与聚集机制，获得摩擦电发电机高功率输出方法，建立接触面积与电输出性能之间的数学模型；明晰超弹性体材料压力—弹性变形响应关系，探明超弹性体材料接触疲劳失效机理及调控机制，揭示超弹性材料在干摩擦面接触条件下的静电耦合摩擦学规律；最终构建出超弹性摩擦发电机的电输出和摩擦学性能综合评价经验公式，为长寿命、高功率摩擦电发电机设计奠定基础，为软体机械的设计与制造提供理论支撑。

随着智能时代的到来，以可穿戴电子、智能无线传感网络等为代表的智能装备要求稳定、易获取、可移动的能源。摩擦纳米发电机由于可高效收集环境的低频机械能而具有广阔的应用前景。项目致力于提高摩擦纳米发电机的输出功率，围绕导电超弹性体材料摩擦纳米发电机的工作原理、样机结构设计、性能表征等开展了系列工作。采用模板法、等离子体刻蚀等方法设计、制造了多种构型的表面，考虑导电超弹性体材料表面织构、表面基团、可拉伸性等物理、化学性能，开展了超弹性体材料在发生大变形过程中接触生电行为及变化规律研究，建立了对应接触面积与电输出性能的理论模型，借助ANSYS、Comsol等模拟软件明晰了超弹性体材料压力—弹性变形响应关系，搭建了接触面积实时观测装置、软体材料摩擦学行为测试装置，揭示出超弹性材料在干摩擦面接触条件下的接触疲劳失效模式及摩擦学规律。在此基础上设计、制造出对应于接触分离、单电极、独立层模式的多面体结构、双螺旋结构摩擦纳米发电机，用以实现对风能、水波能以及人体运动能量的高效便捷收集，最大功率密度达到7.2 W/m2，最终实现原理样机在智能交通、滑觉传感方面的演示。解决了摩擦电发电机中聚合物表面电荷密度提高难及接触界面耦合摩擦学规律不明这两个关键基础问题，为长寿命、高功率摩擦电发电机设计奠定了基础，为柔性机械电子器件与系统特别是自供能传感器和柔性移动能源的设计与制造提供理论支撑。此外，在项目实施过程中，项目组成员积极参加学术交流，在国际、国内会议上做邀请报告、墙报、口头报告等6次，在期刊上累计发表学术论文9篇，授权发明专利8件，培养硕士研究生8人，已经毕业4人，多名学生在各类学科竞赛中获奖，较好地发挥了项目的人才培养职能。