It is necessary to investigate and develop nickel-cobalt sulfide electrodes with superior electrochemical behavior. This work produced the NiCoS/Ni/NiS nanostructure composite (NCS/N/NS) for energy storage in supercapacitors using a solvothermal technique with polyethyleneimine (PEI) as a carbon source, followed by an hour of annealing in an argon atmosphere, and a hydrothermal method with thiourea as a sulfur and nitrogen source. Outstanding electrochemical energy storage properties are provided by NCS/N/NS. The produced electrode material, NCS/N/NS, demonstrated an exceptional capacitance of 1620 F g (696 C g) at 1 A g when employed for SCs. An NCS/N/NS was used as the positively charged electrode and the opposite electrode of commercial AC to build an NCS/N/NS//activated carbon (AC) asymmetric device for practical usage. At 1 A g, the asymmetric device produced a specific power of 887 W kg and a unique specific energy of 53 Wh kg. Moreover, it exhibits a 100% coulombic efficacy and a 95% capacity retention after 3000 cycles, respectively.

中文翻译：

---

用于储能应用的纳米结构 NiCo2S4/Ni/Ni9S8 复合材料的构建

有必要研究和开发具有优异电化学行为的镍钴硫化物电极。这项工作使用溶剂热技术，以聚乙烯亚胺（PEI）作为碳源，生产了用于超级电容器储能的 NiCoS/Ni/NiS 纳米结构复合材料（NCS/N/NS），然后在氩气气氛中退火一小时，并在以硫脲为硫源、氮源的水热法。 NCS/N/NS 提供出色的电化学储能性能。所生产的电极材料 NCS/N/NS 在用于 SC 时，在 1 A g 电流下表现出 1620 F g (696 C g) 的出色电容。使用NCS/N/NS作为带正电的电极和商用AC的相反电极，构建NCS/N/NS//活性炭（AC）不对称装置以供实际使用。在 1 A g 电流下，该不对称器件产生了 887 W kg 的比功率和 53 Wh kg 的独特比能量。此外，它在 3000 次循环后分别表现出 100% 的库伦效率和 95% 的容量保持率。