Dealloyed Porous NiFe₂O₄/NiO with Dual-Network Structure as High-Performance Anodes for Lithium-Ion Batteries

As high-capacity anode materials, spinel NiFe₂O₄ aroused extensive attention due to its natural abundance and safe working voltage. For widespread commercialization, some drawbacks, such as rapid capacity fading and poor reversibility due to large volume variation and inferior conductivity, urgently require amelioration. In this work, NiFe₂O₄/NiO composites with a dual-network structure were fabricated by a simple dealloying method. Benefiting from the dual-network structure and composed of nanosheet networks and ligament-pore networks, this material provides sufficient space for volume expansion and is able to boost the rapid transfer of electrons and Li ions. As a result, the material exhibits excellent electrochemical performance, retaining 756.9 mAh g^-1 at 200 mA g^-1 after cycling for 100 cycles and retaining 641.1 mAh g^-1 after 1000 cycles at 500 mA g^-1. This work provides a facile way to prepare a novel dual-network structured spinel oxide material, which can promote the development of oxide anodes and also dealloying techniques in broad fields.