基于高效单原子催化复合储氢材料体系的构筑及吸放氢热力学动力学

The increasing energy crisis have forced us to accelerate our pace toward renewable hydrogen-energy era.The high hydrogen storage capacity (7.6 wt%), low cost, and environmental friendly properties of MgH2 make it a promising candidate to fulfill the targets of hydrogen application.China has the richest Mg storage source, which account for 22.5% in the world. Based on the advantage of storage capacity, developing advanced Mg-based high hydrogen storage materials have promising applications. However, the practical application of MgH2 is limited by its high thermal stability and sluggish sorption kinetics. Generally, nanostructure can effectively alter the thermodynamics and kinetics of matreials. Based on overview of the process in MgH2, chemical construction method and low-temperature solid method are used to realize the controllable synthesis of nano-structure Mg-based Mg(AlH4)2-MgH2composties, which is fabricated with non-noble metalic catalysts and novel carbon based materials. This novel co-constructed Mg-based nano-materials can effectively modify the hydrogen sorption enthalpy, reduce the dehydrogenation temperature and improve the sorption kinetics of Mg-based hydrogen storage composite.

我国是世界上镁资源最为丰富的国家之一，总储量占世界的22.5%，因此发挥我国的资源优势结合国家重大需求，因此充分发挥我国的资源优势，开发新型高容量镁基储氢材料具有良好的应用前景。基于镁基材料纳米化可有效改善材料热力学性能，调控热力学参数的研究思路，本课题拟利用化学法利用MOF前驱体制备单原子非贵金属与N/P掺杂的多级孔碳材料Ni基、Co基高效催化剂，结合低温固相法机等离子体辅助球磨技术构筑组装高容量储氢复合体系制备镁基Mg(AlH4)2-MgH2复合储氢材料。从而有效调控吸放氢反应焓变，降低反应温度，改善吸放氢过程传质传热性能。并阐明复合体系催化反应机理，为镁基储氢材料的实用化提供理论基础。

安全、高效及经济的氢气储运是实现氢能源实际应用的关键。镁基储氢材料（Mg / MgH2）具有储氢密度高（7.6 wt.%）、循环性能好、环境友好及镁资源价格低廉等优点。针对其存在吸放氢动力学过于缓慢的问题，本课题利用原位固相法文通过添加单原子催化剂对MgH2进行改性。本课题采用固相法原位构筑了纳米MgH2@GNS复合材料，探索了微纳结构镁基储氢材料的原位制备，降低MgH2吸放氢反应温度；开发了准固态球磨-煅烧方法制备单原子M-N-C复合材料，并成功扩展应用于制备第四周期（Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn）及第五周期La、Ce共12种过渡金属对应的M-N-C多种高效催化剂，深入探究了元素组成、元素电负性对材料形貌与结构的影响，采用溶剂热法合成了高热稳定性的M-BTC300（M=Ni、Co）金属有机框架材料催化剂，有效提升了MgH2的放氢动力学，合成了一系列不同有机配体L(L=均苯三甲酸（H3BTC）、联苯二甲酸（H2BPDC）、对苯二甲酸（H2BDC）、间苯二甲酸（IPA）)金属有机配合物催化剂，系统研究了MgH2不同复合储氢体系的吸放氢动力学行为及循环稳定性能。发表论文6篇，其中SCI摘引6篇；申请专利3项，其中2项已授权，培养研究生6名，其中2名已毕业。