具有开放大孔结构的氧化镍/石墨烯/氧化镍夹心纳米管阵列的可控制备及其超电容特性研究

Conductivity and structure stability of NiO are main factors to influence specific capacitance, rate performance and cycling performance of NiO, and technology keys to obtain high pseudocapacitance performance. Based on high strength and high conductivity of graphene, this proposal adopts ZnO template, chemical vapor deposition and electrodeposition to prepare NiO/Graphene/NiO composite nanotube array materials with the sandwiched graphene and open macroporous structure. Graphene shows electric conduction function and structure-enhanced function. The two planes of graphene combined with inside and outside tube wall of nanotube are utilized. In this proposal, the relationship between the main parameters of the synthesis process with sandwich nanotube array structure is investigated systematically, and a controlled synthesis process is proposed. Using cyclic voltammetry and AC impedance, we study the influence and its mechanism of hi-speed conductive framework and composite strengthening effect of graphene on pseudocapacitance properties of NiO, illustrating the significance of graphene and its sandwich structure; studying the relationship between the structure of active materials and nanotube array with pseudocapacitance performances; establishing structure design theory of NiO and nanotube array; obtaining NiO new materials with high pseudocapacitance performances whose features are the sandwiched graphene, NiO inside and outside nanotube, and nanotube array; providing the theoretic and experimental basis for application of graphene and the development of high-performance supercapacitor materials.

NiO的电导率和结构稳定性是影响NiO比电容，倍率性能和循环性能的主要因素，是获得高赝电容性能的技术关键。利用石墨烯的高强高导电性能，本项目采用ZnO模板结合电沉积，化学气相沉积等技术制备具有开放大孔结构的氧化镍/石墨烯/氧化镍夹心纳米管阵列材料，使石墨烯兼备导电功能和结构强化功能，实现石墨烯上下两面和纳米管内外管壁的融合利用。项目系统研究合成工艺主要参数与夹心纳米管阵列结构的关系，建立微结构可控的合成工艺；通过循环伏安、交流阻抗等电化学技术研究石墨烯的高速导电网架和复合结构强化作用对NiO赝电容特性的影响和机制，阐明石墨烯及其夹心结构在NiO电极材料结构中的科学意义；研究活性材料和纳米管阵列的结构与赝电容性能的关系，建立NiO与纳米管阵列材料的结构设计理论。最终获得以石墨烯夹心复合结构，纳米管阵列和管内外负载NiO为特色的NiO新材料，为石墨烯应用和超电容材料开发提供新的理论和实验依据。

通过本项目的研究，掌握了CVD结合电沉积技术生长NiO/G/NiO夹心纳米管阵列材料的工艺流程和实验参数，获得了比电容，倍率性能和循环性能等赝电容性能显著提高的超电容复合电极材料。阐明了石墨烯夹心结构的高速导电骨架和复合结构增强作用对NiO赝电容性能的影响和机制，揭示了石墨烯及其夹心结构在NiO电极材料中的科学意义。此外，通过本项目的研究，还掌握了NiCo2S4纳米管阵列材料和NiCo2O4纳米管阵列材料，CoMoO4纳米片阵列材料和碳包覆、PPy包覆CoMoO4纳米阵列材料，以及NiO/MnO2核壳式复合材料的合成工艺，获得了一系列高性能电化学储能材料。阐明了纳米管结构对NiCo2S4和NiCo2O4材料的电化学储能性能的影响，讨论了纳米片结构与多孔柱结构对CoMoO4赝电容性能的作用及机制，阐明了导电材料PPy和碳的表面包覆对CoMoO4赝电容性能的改善作用，揭示了MnO2表面包覆对NiO赝电容性能和循环稳定性的改进作用。上述工作为赝电容电极材料和锂电池电极材料的研究开发提供了有价值的实验和理论依据。