基于硅基微镜的分级介孔钒氧化物锂离子电池正极材料微力学-电化学性能调控机制与原位表征

Lithium-ion batteries based on hierarchical mesoporous vanadium oxides cathode with high performance, integration, low cost is an advanced and crossed area of applications of micro/nano structure for microdevices and nanotechnology. This proposal focuses on the design of microstructures and micro mechanical systems, and fabrication of vanadium oxides based hierarchical mesoporous composite microstructures by microfabrication processes including electroplating, UV photolithography, lift-off, and deep reactive ion etching of silicon etc. These microfabrication processes can be utilized for the fabrication of silicon micromirror with vanadium oxides based hierarchical mesoporous composite torsional bars. For the fabricated composite microstructures, their morphologies, interfacial structure, compact density will be characterized. Further the in-situ characterizations of the micromechanical properties and corresponding electrochemical properties of various microstructures and the torsional microbars during the application in the silicon micromirror will be conducted. The relationship between the materials structure, scale, diameter, surface defects, and micromechanical properties and electrochemical properties of the microstructures will be investigated. Consequently, the intrinsic relationship between fabrication processes, design of structure and device, properties and optimization approaches will be revealed. To investigate and develop the silicon micromirror for the in-situ characterizations of structure and properties of cathode materials during the electrochemical reactions by controlled fabrication of microstructures, composite's construction, optimization of structural design, and performance regulation. This research will lay a foundation for the in-situ characterizations, energy storage mechanism, and applications of high performance composite microstructures for microdevices.

开发基于钒氧化物及其复合材料分级介孔微纳正极材料的高性能、集成化、低成本的锂离子电池是微纳结构器件化应用和纳米科技的交叉和前沿这一。本项目拟基于微机械系统及微结构的设计，结合电镀法、紫外光刻、剥离浮脱、硅的深刻蚀等微加工工艺制作钒氧化物及其复合材料分级介孔结构，并以此为基础制作采用这一微结构作为扭转梁的硅基微镜器件。表征复合材料微结构的形貌、界面结构、致密度等，原位测试微结构的微力学性能及在器件化应用时的微力学行为和相应的电化学行为。研究材料结构、尺寸、径宽、表面缺陷等因素与微结构的微力学性能及电化学性能间的相互关系，揭示制作工艺、结构设计与微力学性能间的内在联系及优化途径。通过材料和微结构的可控制作、复合构筑、结构优化设计、性能协同调控等探索发展通过新型硅基微镜器件来原位表征电极材料在电化学反应中的结构性能变化，为高性能复合材料微结构的原位表征、储能机理与器件化应用奠定科学基础。

开发基于复合材料的微电极材料，并实现其高性能、集成化和低成本是微纳结构器件化应用和纳米科技的交叉和前沿这一。按照项目的研究计划，以微纳器件加工工艺为基础，我们研究了采用复合材料作为结构和功能单元的微型器件，主要包含集成有复合材料扭转梁结构的微镜器件和微型超级电容器等。如，我们对于多层膜结构的微悬臂梁的力学模型进行了仿真研究，阐明了薄膜物性对于微悬臂梁的微力学行为的影响。我们采用复合材料电极设计、微纳器件工艺、微加工工艺等构筑微型储能器件，并结合传统的光刻工艺与热解碳化等途径，制作了基于碳/碳纳米管复合材料、碳/NiO/Ni、二硫化钼/碳等为微电极材料的微型超级电容器，并系统研究了其电化学性能。在微纳器件的设计及集成工艺研究上，对于复合材料在器件中的集成，以及快速退火工艺，系统研究了工艺优化和性能优化的途径。此外，对于磷掺杂的半导体锗纳米线进行了拉曼光谱表征，对这一材料经N型掺杂后的拉曼峰位的Fano宽化行为进行了理论模型阐述与实验结果验证。