Metal sulfides hollow structures are advanced materials for energy storage applications of lithium-ion batteries and supercapacitors. However, constructing hollow metal sulfides with specific features, such as multi-shell and non-spherical shape, still remains great challenge. In this work, we firstly demonstrate the synthesis of CuS double-shell hollow nanocages using Cu₂O nanocubes as precursors. The synthesis processes involve the repeated anion exchange reaction with Na₂S and the controllable etching using hydrochloric acid. The whole synthesis processes are well revealed and the obtained double-shell CuS is tested as pseudocapacitive electrode material for supercapacitors. As expected, the CuS double-shell hollow nanocages deliver high specific capacitance, good rate performance and excellent cycling stability due to their unique nano-architecture. The present work contributes greatly to the exploration of hollow metal sulfides with complex architecture and non-spherical shape, as well as their promising application in high-performance electrochemical supercapacitors.

中文翻译：

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双壳CuS纳米笼作为先进的超级电容器电极材料

金属硫化物空心结构是用于锂离子电池和超级电容器的储能应用的高级材料。然而，构造具有特定特征（例如多壳和非球形）的中空金属硫化物仍然是巨大的挑战。在这项工作中，我们首先证明了使用Cu ₂ O纳米立方体作为前体的CuS双壳中空纳米笼的合成。合成过程涉及与Na ₂重复进行阴离子交换反应S和可控蚀刻使用盐酸。充分揭示了整个合成过程，并将所得的双壳CuS作为超级电容器的伪电容电极材料进行了测试。不出所料，由于其独特的纳米结构，CuS双壳中空纳米笼具有高比电容，良好的倍率性能和出色的循环稳定性。本工作为探索具有复杂结构和非球形形状的中空金属硫化物及其在高性能电化学超级电容器中的应用提供了极大的帮助。