Zero-Strain High-Capacity Silicon/Carbon Anode Enabled by a MOF-Derived Space-Confined Single-Atom Catalytic Strategy for Lithium-Ion Batteries

Developing zero-strain electrode materials with high capacity is crucial for lithium-ion batteries (LIBs). Here, a new zero-strain composite material made of ultrasmall Si nanodots (NDs) within metal organic framework-derived nanoreactors (Si NDs subset of MDN) through a novel space-confined catalytic strategy is reported. The unique Si NDs subset of MDN anode features a low strain (<3%) and a high theoretical lithium storage capacity (1524 mAh g(-1)) which far surpasses the traditional single-crystal counterparts that suffer from a low capacity delivery. The zero-strain property is evidenced by substantial characterizations including ex/in situ transmission electron microscopy and mechanical simulations. The Si NDs subset of MDN exhibits superior cycling stability and high reversible capacity (1327 mAh g(-1) at 0.1 A g(-1) after 100 cycles) in half-cells and high energy density (366 Wh kg(-1) after 300 cycles) in a full cell. This study reports a new catalog of zero-strain electrode material with significantly improved capacity beyond the traditional single-crystal zero-strain materials.

Automated summary

This study reports a new composite material with zero-strain property, consisting of ultrasmall Si nanodots within metal organic framework-derived nanoreactors. The material exhibits low strain, high theoretical lithium storage capacity, superior cycling stability, and high energy density.