以钼酸和氧化石墨烯为原料,正十二硫醇为还原剂,水热法反应后,在氨气气氛中高温氮化处理,制备出氮化钼/氮化石墨烯(MoN/NGS)复合材料.采用X射线衍射和扫描电子显微镜对材料进行了表征；采用循环伏安法、恒流充放电和电化学交流阻抗研究了该材料用于锂离子电容器的性能.结果表明,MoN纳米颗粒良好地分散在NGS表面和层间,在0.05 A/g的电流密度下质量比容量能达到422 F/g;经过900次充放电循环后,容量保持率在80％以上.当功率为3000 W/kg时,能量密度仍保持在32.5 Wh/kg.这归因于复合材料中的NGS提供了有效的导电网络,并且有效抑制了MoN颗粒的团聚,复合材料的网络结构更有利于离子的快速传输与扩散.%Molybdenum nitride/nitrogen-doped graphene sheets(MoN/NGS)composite was prepared via a simple hydrothermal method followed by calcination at 800℃ under ammonia atmosphere.The phase structure and morphology of samples were characterized by XRD and SEM.The electrochemical properties of composite electrodes were studied by performing cyclic voltammetry,galvanostatic charge and discharge,and electrochemical impedance spectroscopy test.The MoN/NGS electrode deliveres specific capacitance of 422 F/g at the current density of 0.05 A/g,and its capacitance retention remains more than 80％ after 900 cycles.The energy density remains as high as 32.5 Wh/kg when the power density is 3000 W/kg.It should be noted that such improvement should be attributed not only to the presence of NGS in the composite offering an effective conducting network but also to the hybrid structure of MoN/NGS composite providing a favorable and fast ion transport and diffusion.
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