Fe、Co、Ni超细纳米结构制备与催化放氢研究

Efficient and cheap nonprecious metal-based catalysts play key roles in developing controllable hydrogen production/supply systems for fuel cells. In this program, we will exploit controllable preparation strategies for Fe, Co, Ni （≤5nm）with uniform particle size, large specific surface area, high dispersity, and ultrasmall nanostructures. We intend to obtain ultrasmall nanostructured materials having specifically exposed crystal faces and high catalytic activities, and to improve their catalytic stability towards hydrogen generation from hydrolysis of borohydrides (e.g., NaBH4 and NH3BH3). Both experimental and computational studies will be performed to reveal the hydrolytic catalysis mechanism and investigate the relation between catalytic performances and material parameters such as composition, crystal structure, crystal orientation, bulk and surface defects, crystallinity, and so on. The goal of the program is to theoretically and experimentally shed light on the development of well-performing, low-cost nonprecious and ultrasmall metal/alloy nanostructures for catalytic hydrogen generation.

研发高效、廉价的低成本非贵金属催化剂是发展可控制氢和燃料电池供氢系统的关键。项目将探索粒径均一、比表面积大、分散性良好的超细纳米结构Fe、Co、Ni（≤5nm）的梯度可控制备方法，获得具有超细结构、特定晶面取向、高活性的纳米催化剂材料，提高超细纳米结构材料在硼基氢化物（NaBH4和NH3BH3）水解放氢反应中的循环稳定性；结合理论计算结果，获得材料组成、晶体结构、晶面取向、体相及表面缺陷、结晶状态等与其催化性能的关系，以及催化水解反应规律，为研发高效廉价非贵金属超细纳米结构体系及催化放氢提供理论基础和实验依据。

近年来，储氢材料与技术的发展由单纯的可逆储氢系统向可逆/非可逆储氢并行的模式发展，非可逆储氢系统具备典型的氢“制储运”一体化特征，在车载氢源和便携式氢源等领域显示出良好的应用前景。以NH3BH3等为主要成分的轻金属硼基氢化物材料，氢含量均超过10wt%，既可以热解放氢，又可以水解放氢，可满足可逆/非可逆储氢的并行模式而成为高容量储氢材料的研究重点。项目以NH3BH3、Mg(BH4)2等储氢材料为研究对象，采用多孔碳、碳纳米管、基于Fe、Co、Ni基超细纳米结构材料、氮掺杂多孔碳负载的Co纳米颗粒、Ni2P多孔微球等作为载体/催化剂，改善了氨硼烷及Mg(BH4)2等硼基氢化物的放氢性能，以及催化剂的循环使用效率，研究了其可能的吸放氢机理。