Constructing ZnSe/CoSe2/N-doped carbon composite with multiple heterointerfaces using a solvent-assisted strategy to enhance lithium storage

Interface engineering, as an effective strategy for preparing high power density and long-life battery anodes, can promote the electrochemical performance of materials. Herein, metal organic frameworks (MOFs) derived N-doped carbon nanosheets loaded nanoscale ZnSe/CoSe ₂ particle composite with multiple heterointerfaces is fabricated by solvent assisted strategy. Wherein the content of water in the solvent is a key factor in establishing a homogeneous heterojunction containing cubic phase CoSe ₂ (c-CoSe ₂) and orthorhombic phase CoSe ₂ (o-CoSe ₂ ). The built-in electric field generated by the energy band gap difference between ZnSe and CoSe ₂ or c-CoSe ₂ and o-CoSe ₂, and a strong interaction between ZnSe/CoSe ₂ particles and N-doped carbon nanosheets, can reduce the migration barrier of Li ⁺ at the interface, accelerate charge transfer, and promote the lithium storage kinetic process. In addition, nanoscale ZnSe/CoSe ₂ particles coupled with N-doped carbon nanosheets can also generate more active sites, reduce volume expansion, and maintain the structural integrity of the anode material. Based on the above structural advantages, the prepared ZnSe/CoSe ₂-3# exhibits a high reversible capacity (1188 mAh g ⁻¹ after 280 cycles at 0.5 A g ⁻¹), and excellent long-term cycling stability (788 mAh g ⁻¹ at 1 A g ⁻¹ over 600 cycles).