具有高储氢容量及循环稳定性的Ti基准晶复合材料研究

Ti-based quasicrystalline containing icosahedral structure reveals outstanding gaseous hydrogen storage capacity (3 wt.%) implying that this material has potential application prospect as hydrogen storage alloys. Nevertheless, hydrogen storage system of Ti-based quasicrystals demonstrates inactive hydriding/dehydriding process, electrochemical hydrogen storage capacity required to be enhanced and poor cycle life on the basis of our previous work. Moreover, complex hydrides displaying extraordinary theoretical hydrogen storage capacity such as 18.5 wt.% of LiBH4 and graphene and other carbon materials are widely used in the preparation of electrode materials for the large specific surface and good conductivity as well as stable cycle life. Thus, present work plans to further optimize the design and preparation of Ti-based quasicrystalline composite alloys doping complex hydrides applying mechanical ball-milling method and coating graphene or other carbon materials to enhance hydrogen storage properties. We intend to in-depth investigate the hydrogen storage properties of Ti-based icosahedral quasicrystalline composite alloys and analyze the fundamental theory of hydrogen storage properties as well as accumulate data for developing outstanding hydrogen storage properties of new-type Ti-based quasicrystal composite materials. This project is a forward-looking study academically associated with related fundamental theories and practical application of Ti-based quasicrystal materials.

Ti基准晶因其特定的正二十面体构造，具有较高的气态储氢容量（3 wt.%），在储氢材料研究方面拥有潜在的应用前景，但前期的工作表明，该类材料存在可逆吸放氢性能差，以及电化学储氢容量有待提高和循环稳定性较差的问题。为此，本项目以上述问题为出发点，对Ti基准晶材料进一步优化复合制备，采用复合添加具有更高储氢量的碱金属氢化物（如LiBH4，储氢容量高达18.5 wt.%）来提高储氢容量，采用碳/石墨烯对Ti基准晶复合材料进行表面包覆处理来提高储氢循环稳定性。深入研究复合材料的气态和电化学储氢性能，重点研究其作为镍-金属氢化物二次电池负极材料的电化学性能，并进行理论解析，为研制具有高储氢性能的新型Ti基准晶复合材料积累数据，本项目具有方向前沿性和应用基础意义。

研究了TiVNi基准晶复相材料的改性方法、组织构造、物理/化学特性、电化学性能及气态储氢性能等。结果表明，Ti1.4V0.6Ni准晶复相材料具有良好的储氢性能，可作为镍氢电池二次电池负极活性物质。探索了多种添加剂（催化性金属单质、石墨烯、碳纳米管、过渡金属氧化物、过渡金属碳化物、配位金属氢化物等）对Ti基准晶复相材料储氢性能的影响机制，并优化出具有优良储氢性能的Ti基准晶复相储氢体系。本项目在研期间，发表SCI论文10篇，申请中国发明专利3项（其中1项获得授权）。本研究为TiVNi基准晶复相材料的设计和性能研究等提供了理论基础数据和科学依据，为今后继续深入研究奠定了基础。