新型高能过渡金属氮化物固溶体的设计制备及储锂性能研究

The development of high energy density and long cycle life lithium battery anode material is an important problem for its large-scale practical application. Based on our preliminary experiment results and findings and aimed at the issues such as poor rate performance, short cycle life, and the incomplete conversion reactions of the metal nitrides, we propose to design and construct the controllable chemical composition and structure of new type of transition metal nitrides solid solution with high electrochemical performance through in-suit topological transformation of the Prussian blue analogues take the advantage of the cyanide ligands in Prussian blue analogues is easy to be tailored and the composition is easy to be controlled. In this project, we will focus on the design of the Prussian blue analogues and the topological transformation mechanism from Prussian blue analogues to the transition metal nitrides solid solution. The study on the influence rules and the synergistic effect of the composition and structure on the electrochemical performance will be carried out to find out the key constitute and structure factor of the metallic nitride solid solution electrode material for lithium storage. The structure-efficiency relationship between composition, structure and performance will be illuminated and the possible mechanism for improving the electrochemical performance of the transition metal nitrides solid solution will also be proposed. The implementation of the project provides a new way and idea for the design, development and practical application of the transition metal nitrides solid solution electrode materials with excellent electrochemical performance. The research is of great scientific and practical significance to guide the design and preparation of new high-energy solid solution electrode materials and to enrich the basic theory of electrochemical lithium storage.

开发高能量密度和长循环寿命的锂电池负极材料是其大规模实际应用无法回避的重大问题。项目基于前期研究结果和发现，提出利用普鲁士蓝类配位聚合物组成结构易被调控且氰根可被裁剪的设计思路，致力于原位拓扑氮化，设计并构筑可控化学组成和结构的新型高能过渡金属氮化物固溶体。研究普鲁士蓝类聚合体拓扑氮化制备金属氮化物固溶体的合成及转化机理；研究固溶体电极材料的组成、结构对电化学储锂性能的影响规律及协同作用机制；揭示影响电极材料储锂性能和循环稳定性关键的组成和结构因素；深刻理解电极材料储能与转化过程中的微观机理及其相互关联性；提出固溶体电极材料可能的电化学储能性能改善机理。项目的实施为综合服役性能优异的过渡金属氮化物固溶体电极材料的设计、开发以及实际应用开辟一条新的途径和思路。该研究对指导新型高能固溶体电极材料的设计制备和丰富电化学储锂基础理论都具有重大的科学和实际意义。

开发高能量密度和长循环寿命的锂电池负极材料是其大规模实际应用无法回避的重大问题。本项目提出利用普鲁士蓝类配位聚合物组成结构易被调控且氰根可被裁剪的设计思路，致力于原位拓扑氮化，设计并构筑可控化学组成和结构的新型高能过渡金属氮化物固溶体。利用这一新思路设计制备出了多种氮化物固溶体如TiFeN、Cr0.5Fe0.5N等，还将此方法拓展至硫化物、硒化物和碳化物，并合成出Mn0.6Fe0.4S、Mn3Co2C，以及Co0.4Fe0.6Se2/N-C等。通过研究固溶体电极材料的组成、结构对电化学储锂性能的影响规律及固溶体组分原子协同作用机制；揭示影响电极材料储锂性能和循环稳定性关键的组成和结构因素，探索电极材料储能与转化过程中的微观机理。该项目的实施为过渡金属固溶体电极材料的设计、开发以及实际应用开辟一条新的途径和思路。该研究对指导新型高能固溶体电极材料的设计制备和丰富电化学储锂基础理论都具有重大的科学和实际意义。