电化学电容器氮化钒负极材料性能研究

利用高温氨解还原氧化钒（V₂O₅）制备了氮化钒（VN）纳米材料. 采用XRD、SEM与TEM观察分析样品的结构和形貌，采用氮气吸附、循环伏安曲线以及恒流充放电曲线测试样品的比表面积、孔径分布和电极电化学性能. 结果表明，VN样品属于立方晶系（Fm3m [225]），其大小均一，近似球形，氨解时间的加长（12 h），小颗粒间相互交联可形成一定的介孔. 50 mA?g-1电流密度下VN-c电极的比电容能达到192 F.g-¹，1000周期循环其比电容仍有150 F.g^-1，同时具有双电层电容性能和氧化还原反应的准电容性能.

Performance of VN as Negative Electrode Materials in Electrochemical Capacitors

Nanocrystalline vanadium nitride (VN) materials were synthesized by high temperature ammonia (NH₃) reduction of vanadium oxide (V₂O₅). The structure and morphology of VN materials were characterized by XRD，SEM and TEM, while the specific surface area, pore size distribution and supercapacitive behavior by N2 absorption, cyclic voltammetry (CV) and constant current charge-discharge measurements in 1 mol?L-1 KOH electrolyte. The results showed that the VN sample belonged to the cubic crystal system (Fm3m [225])，and had homogeneous surface and appeared nearly spherical with uniform size. As the reaction time was extended to 12 h，small particles were interconnected with each other to form some mesopores. The specific capacitance of VN-c was 192 F.g^-1 at current density of 50 mA.g^-1，and retained 150 F.g^-1 after 1000 cycles. The VN sample possessed both capacitive properties of electrical double-layer and pseudocapacitive properties of redox reactions.