Hierarchical Co₉S₈ hollow microspheres with nanosheet building units are synthesized via a one‐step hydrothermal method. The presence of glucose in the synthesis is essential to the formation of the hollow structure and influences the size and morphology of the microspheres. Benefiting from the advantages of a hollow architecture, a conductive carbon coating and Co₉S₈ nanosheet units, the composite exhibits outstanding electrochemical properties. When the composite electrode is evaluated as the cathode material for supercapacitors, it exhibits a high specific capacitance of 514 F g⁻¹ at 1.0 A g⁻¹ and a capacitance retention of circa 88 % over 1000 cycles at 8 A g⁻¹. On the other hand, the nanosheet‐constructed hollow structure can efficiently promote the electrocatalytic activity of Co₉S₈ toward the oxygen evolution reaction. Due to the fact that Co₉S₈ nanosheets impart largely exposed active sites, the composite exhibits a low Tafel slope of 66 mV dec⁻¹ and no obvious degradation after 12 h water oxidation.

中文翻译：

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分层可控的Co9S8空心微球的简便可控合成，作为高性能电活性材料，用于能量存储和转换

通过一步水热法合成了具有纳米片结构单元的分层Co ₉ S ₈空心微球。合成中葡萄糖的存在对于空心结构的形成至关重要，并影响微球的大小和形态。得益于空心结构，导电碳涂层和Co ₉ S ₈纳米片单元的优势，该复合材料表现出出色的电化学性能。当复合电极被评估为超级电容器的阴极材料时，它在1.0 A g ^-1下表现出514 F g ^-1的高比电容，在8 A g ^-1下1000次循环中表现出约88％的电容保持率。另一方面，由纳米片构成的中空结构可以有效地促进Co ₉ S ₈对氧释放反应的电催化活性。由于Co ₉ S ₈纳米片具有大量暴露的活性位点的事实，该复合材料的Tafel斜率低至66 mV dec ^-1，在水氧化12 h后没有明显降解。