催化释氢导向的多元合金/镶嵌结构高活性晶面选择性合成及其机理研究

Aims at VIII group multi-component alloy system, this project establishes one method of “phase transfer reduction- director reagent controlling-solvothermal”, and plane to realize the high active crystal plane selective synthesis of magnetic multi-component alloy / inlay-structure; Oriented by dehydrogenation catalysis, the series of magnetic alloy dehydrogenation catalysis materials surrounded by active crystal surface can be prepared via the optimization of reaction conditions, such as alloy composition，phase transfer process, director reagent controlling, inlay process, and so on. The dehydrogenation catalysis and further multi-functions can be improved by “synergistic effect of multi-component” and “surface electron structure effect”. Through the investigation of multi-aspect structure-activity relationship about alloy composition and dehydrogenation catalysis, surface structure and dehydrogenation catalysis, inlay-structure and dehydrogenation catalysis, it can be uncover the formation of this new structured magnetic crystal alloys and dehydrogenation catalysis mechanism, and further control the high efficient catalysis of dehydrogenation at fixed points, along edges and selective planes. It will provide the scientific guidance for development of crystal alloy catalyst with high efficiency, low cost and long-life. The investigation not only found a new strategy for the high active crystal plane selective synthesis of dehydrogenation catalysts with multi-component alloy / inlay-structures, but also explores a new way to high efficiency controllable dehydrogenation for chemistry storage hydrogen materials under moderate conditions and the application of hydrogen.

本项目针对VIII族金属多元晶态合金体系，建立一种“相转移还原-导向剂调控-溶剂热方法”，并拟用该方法实现磁性多元合金/镶嵌结构高活性晶面选择性合成；以催化释氢为导向，通过对合金组成、相转移过程、导向剂调控、镶嵌方式等实验条件的优化，获得一系列表面为高活性晶面的磁性多元合金释氢催化材料；以硼氢化合物类化学储氢材料为对象，利用“多组元间的协同效应”和“表面电子结构效应”来提高其释氢催化性能，并拓展多功能性。研究该类晶态多元合金的组成比与催化释氢、表面结构与催化释氢、镶嵌结构与催化释氢等多角度构效关系，揭示这类新结构磁性晶态合金的形成与催化释氢机理，实现定点、延棱、选面的高效可控催化释氢，为具有高效、经济和长寿命合金催化剂的研究提供科学指导。该研究的实施不仅探索了一条多元合金/镶嵌结构高活性晶面选择性合成的新思路，而且为化学储氢材料温和条件下的高效可控释氢及氢能的利用开拓了新的道路。

基于多组元协同效应和表面电子结构效应，通过合金组成结构设计和调控合成的优化，开展了高活性磁性多元合金能源与环境催化材料的构筑研究，主要创新成果如下：首先，提出了“相转移还原-导向剂调控-溶剂热”合成方法，实现了“铁系合金/贵金属”二十面体单晶等特殊三维纳米结构的调控制备，在制氢和甲醇燃料电池电催化等方面展现出卓越的晶面选择性催化活性；其次，发展了“自催化-种籽生长”和“结构调控元素刻蚀”法，制备了“金属/半导体”系列高活性晶面引导的一维复合光催化材料，在环境污染物方面表现出高效的催化活性；再次，创建了同步生长二次组装技术，获得了“铁系金属/碳/贵金属” 夹碳双金属双层核壳球形结构，这类多重界面超结构的材料在常温常压下对硼烷类化合物表现出极高的催化释氢活性，解决了典型富氢难解高能物质的高效可控释放问题；最后，拓展了“界面原位还原”合成“石墨烯-合金”纳米薄层结构，借助石墨烯高效电子传递效应和对均匀分布金属纳米晶的有效利用，表现了兼备高催化活性和高选择性的特性.并且，通过“动力学控制的界面原位还原”过程构筑了 “贵金属/合金”二维超薄层复合活性结构，显示出特异的超顺磁性和电催化活性。为能源材料和保护环境提供了新的发展思路。