三维双连接纳米多孔铜基复合物块体电极材料的制备及能量存储与转化

Worldwide concerns about environmental problems and up-coming depletion of fossil fuels have stimulated strong interest in electrochemical energy storage devices including lithium ion batteries and electrochemical capacitors. The performance of these renewable devices depends intimately on the properties of their materials, which results in great efforts focusing on the development of various electrode materials in the past decades. For new generations of electrochemical energy storage devices with high-power and -energy densities and high charge/discharge rates, not only for applications in consumer electronics but especially for clean energy storage and use in hybrid electric vehicles and large industrial equipments, we need to improve their performance substantially by developing new materials and advancing our understanding of the electrochemical interface at the nanoscale. Therefore, the motivations of this proposal are: (i) to develop three-dimensional bicontinuous nanoporous non-noble metal (Cu)-based electrode materials, in particular nanoporous Cu/transition metal oxide hybrids, by chemical/electrochemical dealloying associated with hydrothermal synthesis technology, for the high-performance lithium ion batteries and electrochemical capactors; and (ii) to elucidate the underlying relationships between the charge/discharge behaviors (rates, stability, and power and energy densities) and the properties of electrode materials such as the composition of composites, the nanoporosity, the size dependent electric conductivity, and the detailed morphology, interfacial structure etc.. Meanwhile, on the basis of the experimental results on the evolutions of nanoporosity and composition of nanoporous Cu and nanoporous Cu/oxide composites, which are to be tailored by controlling the components of Cu-based alloy precursors and the dealloying conditions (temperature, time, critical potential), as well as the hydrothermal parameters (temperature, pH value, concentration of solution, and time etc..), respectively, the mechanisms for the formation and evluation of nanoporous metals, and composites will be studied in detail for proposing the optimized conditions for the fabrication of three-dimensional bicontinuous nanoporous metal-based electrode materials with high performance in the applications of lithium ion batteries and electrochemical capacitors.

本项目拟以具有高导电率纳米多孔铜基电极材料为研究对象，采用去合金化与水热合成技术相结合的方式，通过技术条件控制合成三维双连接纳米多孔铜/过渡金属氧化物块体复合物电极材料。进而阐明复合物成分、纳米多孔性、界面和形貌特征等因素对该类电极材料在锂离子电池和超级电容器元件中的充放电行为的影响规律，并优化其结构和提高其在锂离子电池和超级电容器等元件中的使用性能（能量、功率、倍率/充放电速率和稳定循环性）。同时基于纳米多孔铜及其与过渡金属氧化物的复合物纳米多孔结构和成分演变的实验结果，结合计算机模拟研究母体合金成分间的化学势差、成分变化和去合金化条件对惰性元素在固/液界面的扩散动力学以及纳米结构演变的规律，和金属氧化物在纳米多孔铜上的附载生长机制。

世界范围内化石燃料的广泛使用已经造成了严重的环境污染和破坏,如:大量二氧化碳排放与废气污染、大范围的雾霾、酸雨和水污染,甚至将来的能源危机。国民生活环境与经济发展的不协调已成为社会和国民经济可持续发展日趋面临的严峻挑战，促使着人类社会对绿色新能源的广泛需求。在该国家自然科学基金(青年基金)项目的资助下，围绕项目计划得主要的研究内容，围绕纳米多孔金属基复合物纳米材料在能量存储与转换，及其相关高性能应用开展系统的研究。根据本项目计划，系统研究了化学、电化学条件对铜、金纳米多孔结构的影响和演变，基于不同尺度和氧化或非氧化内表面的亚微米级多孔金属为框架，发展了水热合成、无电电镀、脉冲电沉积、原位氧化等方法合成了系列多级纳米多孔金属/氧化物复合纳米材料。系统研究并揭示了合成条件如：时间、温度、溶液浓度、氧化或还原方式等因素对氧化物在纳米孔道内嵌入形貌、氧化物晶体结构调控，及其对复合材料性能的影响。基于系统的研究结果，提出了实体/纳米多孔金属/氧化物复合材料的设计方案，实现了纳米多孔金属/氧化物与集流器之间的无缝集成，获得了可用于高稳定性、高倍率锂离子电池的复合电极材料和用于生物燃料电池或生物传感高催化活性的电极材料、燃料电池氧还原反应的高催化活性催化剂，高比能量和高比功率的超级电容器电极材料，并构建了柔性超级非对称电容器和微型超级电容器，获得了高比功率和高比能的能量存储。并扩展纳米多孔金属基复合材料的概念，利用聚合物模版法探索了强关联电子氧化物多孔结构电极构建，并研究了其超级电容器的能量存储行为。在Nature Commun., Adv. Sci., Adv. Funct. Mater., ACS Nano, J. Mater. Chem. A, Nano Res., ACS Appl. Mater. & Interfaces, Sci. Rep., J. Mater. Chem. C, RSC Adv.共发表SCI论文16篇，其中影响因子大于10的5篇。发表论文总影响因子为120.309(按照2015年发布的JCR计算)。共被SCI引用152次，其中单篇最高他引69次。