RAFT聚合可控制备过渡金属氮化物/多孔碳复合电极材料

Supercapacitor is a new environmental-friendly and high efficiency energy storage device, while the electrode is the key component of the supercapacitor. Ionomer carbonization, a novel one step approach for fabrication metal nitride/porous carbon composite electrode materials, is proposed in this project. It aimed particularly at widening the cell voltage, improving the specific capacitance and energy density of electrode, which may inhibited the development and application of supercapacitor. Herein, the pore structure of the composite, the loading forms of metal nitride (in or on porous carbon), as well as the mass ratio of metal nitride to carbon could be controlled precisely and simultaneously by RAFT controlled/living polymerization and macromolecules design. Based on above studies, effects of the porous structure and the metal nitride loading form or mass on the capacitance properties of the composites will be systematically investigated. Moreover, the mechanism of electrochemical capacitance and the kinetics of electrode process will be elucidated.

超级电容器是一种环境友好的新型高效储能器件，电极材料是超级电容技术的最核心部分。本项目采用一种全新的制备方法- - 离聚物炭化法- - 一步制备过渡金属氮化物/多孔碳新型复合电极材料，旨在提高比容量、拓宽工作电压，解决制约超级电容器发展和应用的能量密度低的问题。主要是通过RAFT可控聚合和大分子设计技术，在控制复合材料的孔结构的同时，精确调控过渡金属氮化物在多孔碳上的负载方式（包括氮化物在多孔碳孔表面的负载和体相中的负载）、负载量。在此基础上，系统研究孔结构、氮化物负载方式、负载量与复合材料的超级电容之间的关系，阐明这种复合电极材料的电化学容量和充放电过程动力学机理。

本项目创新性的提出采用离子嵌段共聚物/含钒基团体系做为前驱体制备氮化钒/多孔碳复合电极材料，目标在于提高超级电容器的能量密度。通过系统研究得到以下结论：1）离子嵌段共聚物/含钒基团炭化法制备氮化钒/多孔碳的方法可行，操作简单；2）通过调节离子嵌段共聚物上离子嵌段的位置和各个嵌段的分子量实现了负载方式和负载量的控制；3）当氮化钒位于多孔碳的表面并具有一定的厚度时，电化学性能最优；4）制备的氮化钒/多孔碳电极材料具有1.2 V的操作电压，达到了>200 F/g的容量；5）氮化钒/多孔碳和氧化镍组装的超级电容器器件的电位窗口为1.6 V，能量密度达到了16 Wh/kg。