二次锌基电池Nano Zn@C负极的电沉积可控构筑、性能调控及枝晶生长抑制机制研究

Since its advantages which include high energy and high power density, safe and efficient discharge, cheap and nontoxic electrode material, as well as easy fabrication, rechargeable Zn-based battery shows great practical value and development prospect in the field of scale energy storage. However, its cycle life is severely shortened due to the dendritic growth of commercial zinc anode in recharging process, hindering its practical process undoubtedly. This proposal is intended to electrodeposit nanocrystalline zinc composite anode (Nano Zn@C) with high inhibiting ability of dendritic growth on the nano-carbon materials for replacing the conventional zinc anode. Meanwhile, functional mechanism of the additive and influences of electrodeposition parameters on surface morphology, grain size as well as loading capacity of nanocrystalline zinc are illustrated to achieve controllable preparation of Nano Zn@C. By investigating electrochemical properties of Nano Zn@C, the intrinsic relationship between its structure and inhibiting ability of dendritic growth can also be clarified, and then the preparation technology of Nano Zn@C is modified according to experimental results. Moreover, the inhibiting mechanism of dendritic growth is revealed from the viewpoint of electron work function, and the theoretical model of electron work function is constructed, so as to guide the design and synthesis of anode materials for rechargeable Zn-based batteries. Our study provides theoretical guidance for producing high-performance anode materials, therefore is extremely significant to promote the development, application as well as industrialization of rechargeable Zn-based batteries.

二次锌基电池具有高能量密度、高功率密度、放电过程安全高效、电池材料无毒廉价、制备工艺简单等优点，在大型储能等领域具有很高的应用价值和发展前景。然而目前商业化锌负极的枝晶生长问题严重缩短了二次锌基电池的循环寿命，这无疑阻碍了其向实用化发展的进程。本申请拟采用电沉积法在纳米碳材料表面构筑高枝晶生长抑制能力的纳米晶锌复合电极（Nano Zn@C）以替代传统锌负极；同时阐明添加剂的作用机理和电沉积参数对纳米晶锌形貌、晶粒尺寸和负载量的影响规律，从而实现复合电极的可控制备；通过对复合电极电化学性能测试，揭示其结构与枝晶生长抑制能力间的构效关系，并根据实验结果对其制备工艺进行修订；从电子功函数理论角度阐明复合电极的枝晶生长抑制机制，并构建其电子功函数理论计算模型用以指导二次锌基电池负极材料的设计合成。本研究为制备高性能锌负极材料提供了理论指导，对推动二次锌基电池的发展、应用及产业化进程具有重要意义。

二次锌基电池具有高能量密度、高功率密度、放电过程安全高效、电池材料无毒廉价、制备工艺简单等优点，在大型储能等领域具有很高的应用价值和发展前景。然而目前商业化锌负极的枝晶生长问题严重缩短了二次锌基电池的循环寿命，这无疑阻碍了其向实用化发展的进程。本申请采用电沉积法在纳米碳材料表面构筑高枝晶生长抑制能力的纳米晶锌复合电极（Nano Zn@C）以替代传统锌负极；同时阐明了添加剂的作用机理和电沉积参数对纳米晶锌形貌、晶粒尺寸和负载量的影响规律，从而实现了复合电极的可控制备；通过对复合电极电化学性能测试，揭示了其结构与枝晶生长抑制能力间的构效关系，并根据实验结果对其制备工艺进行了修订；从电子功函数理论角度阐明复合电极的枝晶生长抑制机制，并构建了其电子功函数理论计算模型用以指导二次锌基电池负极材料的设计合成。本研究为制备高性能锌负极材料提供了理论指导，对推动二次锌基电池的发展、应用及产业化进程具有重要意义。