二维镍基含氧纳米材料的表面化学修饰及其电催化析氧性能优化研究

Designing highly efficient and stable non-precious metal oxygen evolution reaction (OER) electrocatalysts is of paramount importance for further developing green new energy technologies. In this project, to address drawbacks of the inferior thermodynamic-stability and poor conductivity in nickel-based electrocatalysts, we aim to focus on the thermodynamic stable two-dimensional nickel-based oxygen containing nanomaterials (oxides, hydroxides and their derivatives) and take advantage of surface-chemical modification strategies, for instance, surface anion modification, constructing surface heterojunction, as well as surface complexing to regulate their electronic structure to optimize the OER electrocatalytic performance. Considering the surface chemical reactivity and electron-electron correlation influenced by quantum confinement effect in two-dimensional system, the regulation of electronic structure is proposed to accomplish the enhancement of activity of active sites as well as the increment of integral intrinsic conductivity, realizing the synergetic optimization of the OER electrocatalytic performance and designing highly efficient OER electrocatalysts. Moreover, with the aid of theoretical calculations and electrochemical measurements, we intend to reveal how the surface chemical modifications regulate their electronic structure, as well as the relationship between electronic structure regulation and their OER electrocatalytic performance. The implementation of this project will provide theoretical and methodological guidance for designing and fabrication of highly efficient OER electrocatalysts, laying solid material support for constructing highly efficient energy conversion system.

设计高效稳定的非贵金属析氧电催化剂对于推进绿色新能源技术进一步发展具有重要意义。针对当前已发展的镍基析氧电催化剂的热力学稳定性差以及本征导电性较差等问题，本项目拟以热力学稳定的二维镍基含氧纳米材料(氧化物，氢氧化物及其衍生物)为研究对象，基于超薄结构的表面化学反应性特点和二维量子限域效应下的电子关联作用，通过实施表面化学修饰手段，如表面阴离子修饰、表面构建异质结、表面配位等方法对其电子结构进行调制，实现对其催化位点的活性和整体的本征导电性的协同优化，设计出高效的电催化材料。在此基础上，结合理论计算和电化学测试，揭示表面修饰方法调制电子结构的调控规律，并阐明电子结构调制与催化性能优化的关联性。本项目的开展为设计高效的析氧反应电催化剂提供理论和方法指导，并为研制高效能源转换体系提供材料基础。

经过三年的研究周期，基本完成了其预期研究目标。在2019-2021年期间，项目以镍基二维超薄纳米材料及其结构类似物为研究对象，针对不同材料结构的化学特性，设计不同的表面化学修饰策略，实现了超薄纳米材料的电子结构调制，改变了材料的催化性质（主要集中在催化双氧水分解析氧特性和类芬顿催化反应，可缓解氧缺乏和促进产生高氧化性·OH）和吸光性能（将其吸收光谱从可见光延伸至近红外光范围，可实现高效的光热转换和光声成像）。此外，还研究了这些材料的多模态成像能力，及其在酸性环境下的降解特性和代谢情况，并最终将这类材料的应用拓展到肿瘤治疗领域，为设计高效的诊疗剂提供了一定的理论和实验基础。相关成果在SCI收录期刊上发表论文16篇；培养博士生1名，硕士生4名（已毕业1名，在读3名）；获批国家发明专利一件。