Synergistic effect of urchin-like NiCo2O4/SnS2 nanocomposites toward stable lithium-ion storage

Abstract

Nanocone-assembled urchin-like NiCo₂O₄/SnS₂ (NCOSS) nanocomposites were synthesized via a facile solvothermal method and systematically characterized using XRD, FTIR, Raman, FESEM, TEM, XPS, and BET analyses. The results confirm the formation of a crystalline, mesoporous heterostructure with strong interfacial coupling and a high specific surface area. The unique urchin-like nanocone architecture effectively facilitates ion transport and mitigates volume expansion during cycling. When evaluated as a lithium-ion battery anode, the NCOSS electrode delivered a high initial discharge capacity of 1545 mAh g⁻¹ at 0.1 A g⁻¹, with an initial irreversible capacity loss of 19.91%. Notably, it exhibited excellent cycling stability, retaining 625 mAh g⁻¹ after 200 cycles, and superior rate performance with 88.88% capacity retention from 0.1 to 2 A g⁻¹. Electrochemical impedance spectroscopy revealed reduced charge-transfer resistance compared to pristine NiCo₂O₄ (NCO), while kinetic analysis indicated dominant pseudocapacitive contributions (47.82–70.80%), enabling high reversible capacity at elevated current densities. These results demonstrate that NCOSS is a promising anode material for high-performance lithium-ion batteries.