Co-MOF as Stress-Buffered Architecture: An Engineering for Improving the Performance of NiS/SnO₂ Heterojunction in Lithium Storage

Heterostructures with interfacial effects have exhibited great potential for improving the electrochemical kinetics of electrode materials. However, the application of heterostructures is hampered by complicated synthesis parameters and numerous single components. Herein, a multiple-templating synthesis strategy is proposed to improve the interfacial effect of heterojunction composites, mitigate volume variation upon lithiation/de-lithiation, and increase interfacial compatibility with poly-oxyethylene-based (PEO-based) electrolytes. Benefiting from the structural and compositional superiorities, the novel NiS/SnO₂/MOF (NSM) electrode achieves superior electrochemical performance with exceptional specific capacity, outstanding rate capability and ultralong cyclability. As a result of the compatibility between organic components and the porous properties of metal organic frameworks (MOFs), the NSM electrode exhibits greater interfacial compatibility with PEO-based solid-state electrolytes. This work not only describes a meticulous protocol for heterostructured high-performance electrode materials, but also provides a new insight to enhance the connectivity between the interfaces of solid-state batteries.