离子液体参与调控金属磷化物纳米材料合成及其电解水制氢研究

Metal phosphide nanomaterials, as excellent electrocatalysts, have exhibited promising applications in the field of electrochemical water splitting for hydrogen production. Based on the unique tunable role of the ionic liquid on the synthesis of the nanomaterials, this project proposes a new synthesis route for metal phosphide nanomaterials by using the ionic liquid as the reaction medium. The main research contents include: 1) The effects of ionic liquids with various structure, various phosphide source and various organometallic compounds (or metal salt) on the morphology, the structure, the composition, the size, the property and the formation mechanism of metal phosphide are investigated, and the role of the ionic liquid on controlling the growth of the materials are uncovered. 2) By controlling the morphology, structure, composition and size of metal phosphide nanomaterials, and optimizing their electrocatalytic properties for electrochemical water splitting for hydrogen production, the optimum metal phosphide electrocatalysts can be obtained. 3) The synthesis without additional additives for directing the growth of metal phosphide nanocrystals will be explored, and the ionic liquids can fully play their roles for controlling synthesis of nanomaterials, and the easy and accurate formation mechanism will be revealed. The present project is helpful for developing simple synthesis route for the fabrication of new metal phosphide nanomaterials, uncovering the role of the ionic liquid on the formation of metal phosphide nanomaterials, building the relationship between the electrochemical water splitting for hydrogen production and the morphology, structure, composition and size of metal phosphide, and the electrocatalysts with remarkable electrocatalytic properties towards electrochemical water splitting for hydrogen production can be obtained.

金属磷化物纳米材料作为优异的电催化剂在电解水制氢领域已展示出广阔的应用前景。本项目通过离子液体参与合成纳米材料的特异调控作用，提出利用离子液体为反应介质合成金属磷化物纳米材料的新思路。主要研究内容：1）研究不同结构离子液体、不同磷源和不同金属有机化合物（或金属盐）等对所制金属磷化物的形貌、结构、组成、尺寸、性质和生长机制的影响规律，揭示离子液体在材料生长过程中的调控作用机制。2）通过调控金属磷化物纳米材料的形貌、结构、组成及尺寸，优化其电解水制氢的催化性能，筛选出高效电催化剂。3）探索不需外加金属磷化物纳米晶生长辅助剂，发挥离子液体在纳米材料合成中的调控作用，描绘出简单、准确的生长机制。本项目研究有助于发展制备新型金属磷化物纳米材料的简单方法，阐明离子液体在金属磷化物纳米材料制备中的作用机制，建立电解水制氢性能与金属磷化物的形貌、结构、组成及尺寸之间的构效关系，获得高效电解水制氢催化剂。

氢气作为一种清洁能源引起人们的广泛重视。电催化产氢因其具有绿色可持续性等优点在产氢领域具有广阔的应用前景。尽管贵金属基催化剂对电解水反应中的产氢或析氧具有良好的催化效果，但价格昂贵、资源匮乏等原因限制了其大规模应用。因而发展非贵金属基催化剂用于电解水反应具有重要的研究意义。离子液体在合成高效纳米催化剂方面已展示出独特的优势，但有关离子液体合成高效电解水催化剂方面的研究较少。本项目利用离子液体合成金属磷化物等非贵金属纳米催化剂用于电解水反应。研究了不同结构的离子液体对所合成的非贵金属基纳米材料的形貌、结构、组成、尺寸、性质和生长机制的影响，探索了离子液体中纳米材料的生长规律和生长机制。通过对纳米材料生长规律以及离子液体对材料生长的调控规律的研究，阐明了离子液体的作用机制，为构筑高效电解水催化剂提供了理论基础。合成出的非贵金属基纳米材料对电解水产氢具有较低的过电位、较小的塔菲尔斜率和较高的法拉第效率。并且所构筑的析氧催化剂同样具有较低的过电位、较小的塔菲尔斜率。因而，所制备的催化剂在电解水领域具有重要的应用前景。同时，通过催化剂结构和电解水性能之间的构效关系研究，阐明了催化剂活性位点的影响因素，为合理设计电解水催化剂提供了理论依据。本项目研究结果为设计高效电解水催化剂提供了新思路，特别是，有关离子液体对催化剂长过程中的调控机制的研究结果有助于为高效催化剂的设计提供理论依据。本项目所合成的纳米材料有助于为电解水领域提供重要的非贵金属基纳米催化剂。