ABSTRACT Co3O4 has been extensively studied as a potential electrode material for supercapacitors. However, it has some limitations such as low conductivity and ion diffusion that have hindered its widespread application. To overcome the low electron transport efficiency of Co3O4 electrodes, a combination of in-situ precipitation and carbon-assisted methods were performed to synthesize a composite consisting of Co3O4 uniformly dispersed on the surface of graphitic carbon nitride (Co3O4/g-C3N4). In this work, electrochemical measurements in a 6M KOH electrolyte reveal that the Co3O4/g-C3N4 composite electrode exhibits a higher specific capacitance (1071 F g-1 at a current density of 1 A g-1) than the pure Co3O4 electrode (217 F g-1 at 1 A g-1). After 4000 cycles, the capacitance remain 80% of its original value. The Co3O4/g-C3N4 electrode also showed excellent electrical conductivity and low resistance, as determined using electrochemical impedance spectroscopy. Moreover the Co3O4/g-C3N4//AC asymmetric device with this electrode delivered energy density is 20.4 Wh kg-1 at the power density is 0.8 kW kg-1. The results illustrate that Co3O4/g-C3N4 composites show great promise for application in supercapacitors.

中文翻译：

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Co3O4/g-C3N4 纳米复合材料的原位沉降和碳辅助合成相结合以提高超级电容器的性能

摘要 Co3O4 作为超级电容器的潜在电极材料已被广泛研究。然而，它具有导电性低、离子扩散等局限性，阻碍了其广泛应用。为了克服 Co3O4 电极电子传输效率低的问题，采用原位沉淀法和碳辅助方法相结合，合成了由均匀分散在石墨氮化碳表面上的 Co3O4 复合材料（Co3O4/g-C3N4）。在这项工作中，在 6M KOH 电解液中的电化学测量表明 Co3O4/g-C3N4 复合电极比纯 Co3O4 电极表现出更高的比电容（1071 F g-1，电流密度为 1 A g-1）（217 F g-1 在 1 A g-1)。4000 次循环后，电容保持其原始值的 80%。Co3O4/g-C3N4 电极还表现出优异的导电性和低电阻，如使用电化学阻抗谱测定。此外，具有该电极的 Co3O4/g-C3N4//AC 不对称装置在功率密度为 0.8 kW kg-1 时提供的能量密度为 20.4 Wh kg-1。结果表明，Co3O4/g-C3N4 复合材料在超级电容器中的应用前景广阔。