To effectively enhanced structural stability and cycling performance

a dual carbon protection strategy is proposed to fabricate Si nanoparticles encapsulated in citric acid (CA)-derived inner carbon layer and zeolitic imidazolate framework-67 (ZIF-67) derived outer carbon layer (Si@C-CA@c-ZIF). The results reveal that citric acid-derived carbon facilitates a uniform ZIF-67 coating on the Si surface and serves as the inner carbon precursor to reduce volumetric expansion of Si particles

more importantly

it can enhance the transport of electrons and ions between Si particles and ZIF-67-derived carbon. The ZIF-67-derived outer carbon layer further restricts Si particle expansion and enhances conductivity. Evaluated as anode material for lithium ion batteries

the Si@C-CA@c-ZIF anode demonstrates outstanding lithium storage performance

the high specific capacity is high to 924 mA·h·g

-1

at 1.0 A·g

-1

after 10 cycles of activation

and it still maintains a reversible capacity of 703.3 mA·h·g

-1

after 1000 cycles

along with a capacity retention of 76.1%. This work highlights the effectiveness of the dual carbon framework in addressing the volume expansion and conductivity limitations of Si

with potential applications for other high-capacity anode materials.