PDMS中填充铁电和导电纳米材料对增强摩擦纳米发电机的电荷积累和转移的机理研究

Self-powered sensing technology by collecting energy from ambience is an idea strategy to realize the application of wireless sensors in large scale. Triboelectric nanogenerator (TENG) is a device for harvesting mechanical energy from ambience to transform the energy into electricity. Since the first report of the TENG in 2012, it has been developed very rapidly. Up to now, various TENGs and self-powered wireless sensing prototype devices have been achieved by collecting energy from environment. However, poor understanding of energy conversion mechanism in materials for TENGs has hindered the further development for obtaining high efficiency triboelectric nanogenerators. Therefore, in this project, we will study the mechanism of charge accumulation and transfer in TENG from materials view. We plan to investigate the influence on the charge accumulation from composite, constitution, polarization, dielectric properties of the material obtained by filling ferroelectric and conductive nanomaterials into polydimethylsiloxane (PDMS). Meanwhile, we will find the changes of the charge accumulation on the PDMS by varying the morphology and size of filling materials, coupling between filling materials and PDMS, constitution in the PDMS composite. The investigation will be carried out systematically in the route of “synthesis-characterization–measurement-analysis-modeling-calculation”. This investigation will provide the principles for designing the triboelectric materials and provide fundamental parameters to improve the conversion efficiency of TENG.

从周围环境获取能量的自驱动传感技术是实现无线传感器大规模应用的理想方案。摩擦纳米发电机是收集环境能量转换成电能的器件，从2012年第一次报道至今，发展非常迅速，已经实现了多种不同环境能量收集和转换的模型发电器件和自驱动无线传感器的原型器件。但是，对摩擦纳米发电的物理机制与材料科学问题理解的欠缺，成了纳米发电技术进一步发展及高性能纳米发电机研究发展的瓶颈。对此，本项目从摩擦发电材料的设计和制备着手，通过对PDMS中填充铁电和导电纳米材料研究复合材料的组成、织构、极化、介电性对增强接触过程中电荷转移的机理，并通过所填充纳米材料的形貌和尺寸调控，表面修饰与基体材料偶联的设计，组织构形与遂穿电流关联等研究它们对电荷积累的影响，以“合成-表征-测试-分析-模型-计算”为手段，系统地研究摩擦发电的物理机制与材料科学问题。该研究的开展，将为摩擦发电材料的设计提供依据，为制备高性能的复合材料奠定基础。

本项目针对摩擦纳米起电的物理机制与材料科学问题理解的欠缺，从摩擦材料的设计和制备着手，完成了在PDMS中填充铁电和导电纳米材料后其组成、织构、极化、介电性对增强电荷转移机理的研究，给出了计算复合膜有效介电常数计算公式，提出了嵌入式可变微电容模型等，发现了决定介电材料表面电荷密度的关键因素，并通过复合膜的优化，获得ZnSnO3填充膜的摩擦纳米发电机（TENG）最大输出功率是纯PDMS膜的6.2倍；同时开创了新的提高电荷密度和输出功率的方法，刷新了TENG面电荷密度的世界纪录，其输出功率是纯PDMS膜TENG的27倍。将TENG技术应用在人机交互中，首次实现了感官控制的人机交互系统，研发了高灵敏度的声音传感器和人工耳蜗。该项目在TENG的电源管理，器件基础物理和材料科学问题方面取得了重大突破，为摩擦发电材料的设计提供依据，为TENG走向应用提供了科学和技术的支撑。发表标注该基金项目的SCI论文61篇，其中，Science和Nature子刊3篇，影响因子大于10的28篇，高被引/热点5篇，申请发明专利8项，获授权5项。培养博士6人，硕士6人，获得2018年重庆市教委优秀导师团队。参加国际会议30余人次，分会邀请报告8人次，担任分会主席/主持7人次。获得2017年中国产学研合作创新成果奖优秀奖。主办第三届纳米发电机与微纳系统研讨会。