The development of electrochemical supercapacitors has attracted a lot of attention in recent years because of the increasing demand for efficient, high-power energy storage. However, SCs' energy storage capacity is still relatively low. Herein, the ternary metal sulfide CoNiCu with an octahedral hollow structure is obtained by introducing Cu²⁺ with great conductivity and etching with hydrothermal vulcanization. The samples exhibit outstanding performance in the supercapacitor due to the synergistic effect of Co, Cu and Ni. Experimental results prove that its specific capacitance is 2047 F g⁻¹ at 1 A g⁻¹. On the other hand, the supercapacitor device demonstrates a remarkable energy density of 87.8 W h kg⁻¹ when subjected to a power density of 632.0 W kg⁻¹, along with outstanding cycling performance (maintaining 92.86% of its capacity after 20 000 cycles at 10 A g⁻¹). Our work offers a simple hydrothermal vulcanization etching method for synthesizing trimetallic sulfides, which shows good prospects for electrochemical energy storage applications.

中文翻译：

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离子刻蚀调节高性能超级电容器硫化钴的合成

近年来，由于对高效、大功率储能的需求不断增加，电化学超级电容器的发展引起了广泛关注。然而，SCs的储能能力仍然较低。本文通过引入具有良好导电性的Cu ²⁺并通过水热硫化刻蚀得到具有八面体中空结构的三元金属硫化物CoNiCu 。由于Co、Cu和Ni的协同作用，样品在超级电容器中表现出优异的性能。实验结果证明其在1 A g ^-1时的比电容为2047 F g ^-1。另一方面，当功率密度为632.0 W kg ^-1时，超级电容器装置表现出87.8 W h kg ^-1的显着能量密度，以及出色的循环性能（在20 000次循环后仍保持92.86%的容量） 10 A g ^-1 )。我们的工作提供了一种简单的水热硫化蚀刻方法来合成三金属硫化物，这在电化学储能应用中展现了良好的前景。