NiCo_(2)S_(4)/g-C_(3)N_(4)柔性叉指型超级电容制备与电化学性能

Fabrication and Electrochemical Performance of Flexible Interdigital Supercapacitor Based on NiCo_(2)S_(4)/g-C_(3)N_(4) Hybrid

近年来,随着柔性电子的快速发展,制造柔性、微型、大面积和低成本的储能器件得到了极大的关注。以六水硝酸镍/钴为原料、硫脲为硫化剂、引入热解g-CN,通过一步溶剂热制备NiCo_(2)S_(4)/g-CN纳米复合材料。采用掩膜版将调配的NiCo_(2)S_(4)/g-CN油墨印刷在柔性聚对苯二甲酸乙二醇酯基底形成叉指结构电极,继而涂覆凝胶电解质组装成柔性叉指型超级电容器。结构和电化学性能研究表明:NiCo_(2)S_(4)纳米晶分布生长在g-CN纳米片层表面,引入的g-CN起到增强NiCo_(2)S_(4)充放电过程中的电荷传输及容纳其体积膨胀的作用,复合材料电极在10 m A/cm^(2)的电流密度下面积比电容为9.1 F/cm^(2)。组装的叉指电容器可在–0.2~0.6 V的电压下工作,并且在高至500 m V/s的扫描速率下保持稳定,表明器件良好的倍率性能。在20 m V/s的扫描速率下,器件的面积比电容可达5.7 m F/cm^(2),当功率密度为17.5 m W/cm~3时,器件的能量密度为0.56 m W·h/cm^(3)。

The manufacture of flexible,miniature,large-area and low-cost energy storge units has attracted much attention with a rapid development of flexible electronic devices.In this paper,NiCo_(2)S_(4)/g-CNnanocomposite material was prepared via a one-step solvothermal process with nickel and cobalt nitrate hexahydrate as raw materials,thiourea as a vulcanizing agent and pyrolysis g-CN.The interdigital electrode of NiCo_(2)S_(4)/g-CNwas created via mask printing on a polyethylene glycol terephthalate flexible substrate with the well-prepared ink.The flexible interdigital supercapacitor was obtained by coating a layer of gel electrolyte.Based on the structure and electrochemical performance characterizations,NiCo_(2)S_(4)nanoparticles dispersedly grow on g-CNnanoplates,thus improving the charge transfer and accommodating the volume expansion of NiCo_(2)S_(4)during charge–discharge cycles.The area specific capacitance of the nanocomposite electrode is 9.1 F/cm^(2) at a current density of 10 mA/cm^(2).The assembled supercapacitor can operate at–0.2–0.6 V and remainsstable at a scanning rate of 500 m V/s,revealing a good rate performance.The area specific capacitance of the device is5.7 mF/cm^(2) at a scanning rate of 20 mV/s,and the energy density is 0.56 mW·h/cm^(3) at a power density of 17.5 mW/cm^(3).