The hierarchical CuCo₂O₄@carbon quantum dots (CQDs) hollow microspheres constructed by 1D porous nanowires have been successfully prepared through a simple CQDs-induced hydrothermal self-assembly technique. XPS analysis shows the CuCo₂O₄@CQDs possesses the Co(II)-rich surface associated with the oxygen vacancies, which can effectively boost the Faradaic reactions and oxygen evolution reaction (OER) activity. For example, the as-synthesized 3D porous CuCo₂O₄@CQDs electrode exhibits high activity toward overall electrochemical water splitting, for example, an overpotential of 290 mV for OER and 331 mV for hydrogen evolution reaction (HER) in alkaline media have been achieved at 10 mA cm^–2, respectively. Furthermore, an asymmetric supercapacitor (ASC) (CuCo₂O₄@CQDs//CNTs) delivers a high energy density of 45.9 Wh kg^–1 at 763.4 W kg^–1, as well as good cycling ability. The synergy of Co(II)-rich surface, oxygen vacancies, and well-defined 3D hollow structures facilitates the subsequent surface electrochemical reactions. This work presents a facile method to fabricate energetic nanocomposites with highly reactive, durable, and universal functionalities.

中文翻译：

---

Co（II）占主导地位和氧空缺的CuCo ₂ O ₄ @CQDs空心球的合理设计，以提高总水分解和超级电容器的性能

通过一维CQDs诱导的水热自组装技术已经成功地制备了由一维多孔纳米线构成的分层CuCo ₂ O ₄ @碳量子点（CQDs）中空微球。XPS分析表明，CuCo ₂ O ₄ @CQDs具有与氧空位相关的富Co（II）表面，可以有效地促进法拉第反应和氧释放反应（OER）活性。例如，合成后的3D多孔CuCo ₂ O ₄@CQDs电极对整体电化学水分解具有很高的活性，例如，在碱性介质中，分别在10 mA cm ^–2时，OER的过电势为290 mV，氢释放反应（HER）的过电势为331 mV 。此外，非对称超级电容器（ASC）（CuCo ₂ O ₄ @ CQDs // CNTs）在763.4 W kg ^–1时可提供45.9 Wh kg ^–1的高能量密度，并具有良好的循环能力。富含Co（II）的表面，氧空位和定义明确的3D中空结构的协同作用有助于后续的表面电化学反应。这项工作提出了一种简便的方法来制造具有高反应性，耐用性和通用功能性的高能纳米复合材料。