FeSe₂ nanoparticles decorated nitrogen-doped carbon nanocubes for superior lithium-ion batteries

FeSe₂ shows superior advantages as anode of lithium-ion batteries (LIBs) with abundant resources, high theoretical specific capacity, and environmentally friendly. However, the FeSe₂ anode still faces great challenges balancing specific capacity, capability, and stability. In this work, we employ a self-sacrifice template of Fe-PBA coated with polydopamine to prepare FeSe₂@Void@NC cubic nanostructures by one-step pyrolysis and selenization. The experimental results well elucidate the unique hollow cubic architectures with high surface area and abundant pore structure induce rapid adsorption storage, thus improving electrochemical kinetics. Benefiting from the enhanced ion diffusion kinetics and high conductivity through N-doped carbon coating, the FeSe₂@Void@NC electrode demonstrates a considerable capability with a high specific capacity of 493.93 mAh g⁻¹ (3 A g⁻¹), and a stable cyclability with a reversible capacity of 498.5 mAh g⁻¹ (1 A g⁻¹) after 750 cycles. The full cells with FeSe₂@Void@NC anode and LiFePO₄ cathode also exhibit remarkable rate capability and stable cyclability. Our research provides profound insights into the structure engineering of alternative transition metal sulfide anode for LIBs with excellent electrochemical performance.