A two-dimensional heterostructure, combined with the collective advantages of single building blocks, has attracted considerable interest as a new paradigm in the materials design of electrochemical energy storage. In the present study, a sandwich-like CoNi₂S₄/Ti₃C₂T_x heterostructure electrode was successfully acquired using a simple one-step hydrothermal procedure, where CoNi₂S₄ nanosheets are distributed uniformly within the MXene interlayers and on surfaces. The layered structure of MXene restricts the overgrowth of CoNi₂S₄. The tiny size shortens the charge transfer and ion diffusion pathway and minimises the volume change in CoNi₂S₄. The introduction of CoNi₂S₄ expands the interlayer distance of the host MXene, enabling fast ion movement and efficiently accommodating the volume expansion of CoNi₂S₄. The electronic coupling of the metal in CoNi₂S₄ and O in Ti₃C₂T_x improves the electrical conductivity and optimises the absorbability and stability of OH^– on the heterostructure. The CoNi₂S₄/Ti₃C₂T_x heterostructure delivered a capacity of 320 mAh g^–1 (2398 F g^–1) at 1 A g^–1 and a capacity retention of 80% at 25 A g^–1 after 40, 000 cycles, outperforming most supercapacitor electrode materials reported to date owing to the synergy between the structural configuration and electronic interactions. This work provides valuable insights for designing high-performance electrode materials by manipulating the structural configuration and interface electronic interaction.

二维异质结构结合单一构件的集体优势，作为电化学储能材料设计的新范例引起了人们的极大兴趣。在本研究中，使用简单的一步水热程序成功获得了三明治状 CoNi ₂ S ₄ /Ti ₃ C ₂ T _{x异质结构电极，其中 CoNi 2} S ₄纳米片均匀分布在 MXene 夹层内和表面上. MXene的层状结构限制了CoNi ₂ S _{4的过度生长}. _{微小的尺寸缩短了电荷转移和离子扩散路径，并最大限度地减少了 CoNi 2} S ₄中的体积变化。CoNi ₂ S ₄的引入扩大了主体 MXene 的层间距离，实现了快速离子移动并有效地适应了 CoNi ₂ S ₄的体积膨胀。CoNi ₂ S ₄中的金属和 Ti ₃ C ₂ T _x中的 O 的电子耦合提高了电导率并优化了 OH ^-在异质结构上的吸收能力和稳定性。CoNi ₂ S ₄ /Ti₃ C ₂ T _{x异质结构在 1 A g} ^–1时提供 320 mAh g ^–1 (2398 F g ^–1 )的容量，在 40, 000 次循环后在 25 A g –1 时容量保持率为 80%，优于大多数^超级电容器由于结构配置和电子相互作用之间的协同作用，迄今为止报道的电极材料。这项工作通过操纵结构配置和界面电子相互作用为设计高性能电极材料提供了有价值的见解。