过渡金属磷化物的合成与电催化析氢性能研究

Transition metal phosphides have special triangular prism-shaped crystal structures which are abundant in surface unsaturated coordination atoms. Thus they perform high metallicity and conductivity and could be a novel kind of promising electrocatalysts. This project makes use of transition metal salts and phosphates as precursors for synthesizing transition metal phosphides as efficient electrocatalytic hydrogen evolution reaction (HER) catalysts through solid- and liquid-phase reaction with specific morphologies adjusted by templates and coordination agents. By modifications of synthesis reaction conditions, transition metal phosphides with uniform composition, controlled morphology, large specific surface area and abundant HER catalytic active sites could be obtained. After measurements of HER electrocatalytic performances, many important performance indexes of the catalysts will be gained and then we could explore the nature of catalytic activities assisted by composition and structure characterizations and theoretical computation and simulation. Finally, we will understand the relationship between microscopic structures and catalytic performances of the catalysts to further instruct the design and synthesis of transition metal phosphides catalysts and provide technical and theoretic supports for the development of highly-active HER electrocatalysts.

过渡金属磷化物具有三角棱柱形的特殊的晶体结构，表面配位不饱和的原子数目较多，因而表现出较强的金属性和导电性，是一类具有优良前景的新型电催化剂。本项目以过渡金属的盐类和磷酸盐作为前驱物，适当辅以模板及配位剂调节形貌，通过固相及液相反应法合成过渡金属磷化物，高效应用于电催化析氢（HER）反应。通过对合成反应条件的优化，获得成分均一、稳定，形貌可调控，比表面积大，HER催化活性位点暴露较多的过渡金属磷化物，使其具有较高的催化活性。通过对催化剂HER电催化性能的测试，获得多项关键性能参数，并结合结构成分表征和理论计算模拟，分析探讨其高催化活性的本质。研究重点在于表面不饱和配位的金属-磷相位点，揭示过渡金属磷化物HER电催化活性的机制，理解催化剂材料的微观结构与电催化性能之间的联系，以进一步指导过渡金属磷化物催化剂材料的设计与合成，为发展高性能析氢反应电催化剂提供技术指导和理论支持。

氢气是一种清洁的可持续能源材料，将来有可能取代化石燃料。电催化方法制备氢气被认为是目前最有效的制备方法之一，但是其较高的过电位限制了氢气的大量制备。因此，发展一种高效、低廉的电催化材料，是目前急需解决的问题。过渡金属磷化物具有三角棱柱形的特殊的晶体结构，表面配位不饱和的原子数目较多，因而表现出较强的金属性和导电性，是一类具有优良前景的新型电催化剂，可应用于电催化析氢（HER）反应。本项目合成出了以植酸为磷源制备氧掺杂磷化钼阴极与磷化钴阳极、具有析氢析氧双功能的磷化钴、碳包覆的中空介孔磷化铁、磷化钴碳纳米管复合物、磷化钴和二磷化钴的混晶等多种过渡金属磷化物电催化剂，研究了磷化物材料多种结构特异的微观结构，获得了性能优良的电催化性能，并应用于析氢反应。