自支撑多孔碳/Ni(S1-xPx)2电极的构筑及其电催化全分解水性能研究

The band structure and electronic property of the electrocatalyst dominate its charge transport properties and adsorption free energy, which is an important factor to determine the efficiency of electrocatalytic water splitting. Gradient composition in solid solution-based electrocatalytic system endows it with finely adjustable electronic structure, which is expected to bring new perspectives and open up new opportunities for design strategy in the field of electrocatalytic water splitting. On the basis of our previous work, this project will chose Ni(S1-xPx)2 solid solution to construct the electrocatalytic overall water splitting systems. The composition and surface/interface properties of Ni(S1-xPx)2 solid solution are optimized in terms of the synthetic strategy based on MOFs, simultaneously coupling of MOFs-derived porous carbon to extend functionality. We will design and construct the self-supported porous carbon/Ni(S1-xPx)2 electrode on conductive substrate. A methodology for construct solid solution based composite electrodes using MOFs will be developed and established. It reveals the related laws about the effect of composition synergism, electronic structure and adsorption free energy in solid solution electrocatalyst on the electrocatalytic performance. It also elucidates the composition and structure characteristics of the solid solution with high activity and good stability towards water splitting. Furthermore, we will discuss and understand the root of the best electrocatalytic performance in the solid solution system to providing theoretical support and experimental basis for the design, preparation and screen of high efficiency and low cost electrocatalyst for overall water splitting, and thus to promote the theory development and practical application of the electrocatalytic water splitting.

电催化剂的能带结构与电子性质支配着电荷输运特性和吸附自由能，是决定电催化分解水效率的重要因素。固溶体电催化系统中的渐变组成能赋予其精细可调的电子结构，有望给电催化分解水领域开辟全新的设计途径和发展视角。本项目在前期工作基础上，选择Ni(S1-xPx)2固溶体构建电催化全分解水系统，基于MOFs合成策略优化Ni(S1-xPx)2固溶体的组成结构和表界面性质，并同步耦合MOFs衍生的多孔碳获得功能拓展。拟在导电基底上设计和构筑多孔碳/Ni(S1-xPx)2自支撑电极，发展并建立基于MOFs构筑固溶体基复合电极的方法学，揭示固溶体电催化剂的组成协同、电子结构和吸附自由能对电催化性能影响的相关规律，阐明高活性高稳定性固溶体电催化剂的组成结构特征，进而探讨固溶体系统中电催化性能择优的根源，为高效廉价全分解水型电催化剂的设计、制备和筛选提供理论支撑和实验依据。

组成优化与电子结构调控是开发高效电催化水分解材料的关键环节。本项目主要围绕镍基过渡金属电催化材料的设计制备、组成结构优化、电催化特性及其构效关系，着重研究了基于金属-有机框架（MOFs）导向构筑过渡金属电催化系统的合成方法学，发展了通适的MOFs衍生合成策略制备了组成结构可控的多种过渡金属硫化物和磷化物电极材料（如NiS2、Ni3S4、quasi-Ni-BDC-Ni2P、RuCo-RuCoOx-NC）。针对双金属电催化过程中独特的电子效应，设计构建了几类层状电催化材料体系（如铁掺杂硝酸根插层的氢氧化镍纳米片、层状镍铁甘油酸盐微球、层状磷酸根修饰的镍钴硅酸盐微球、层状无机-有机氢氧化镍钴杂化纳米带），揭示了电子效应在镍铁基电催化体系中的作用与功能。设计构建了几类新型异质结构电催化材料（如CoP-FeP异质结电催化剂、MoS2/Ti3C2异质结构电催化剂、多组成Co-Mo2C@NCNT电催化剂、Ru-RuO2-NC异质结电催化剂），研究了这些多元组成电催化材料中异质结效应对电子结构、电荷传输特性的影响规律及其构效关系，揭示了结构耦合与电催化性能之间的内在联系。此外，在quasi-Ni-BDC-Ni2P电催化体系中实现了光热-电催化功能集成，提出了太阳能全光谱光热协助电催化分解水新方法。