Enhanced lithium extraction from brine using surface-modified LiMn₂O₄ electrode with nanoparticle islands

Lithium is an important raw material for new energy-powered vehicles, and ensuring its supply is of great significance for global green and sustainable development. Salt lake brine is the main lithium resource, but the separation of Li⁺ from coexisting metals poses a major challenge. In this work, a lithium-storing metal oxide SnO₂ nanoparticle island-modified LiMn₂O₄ electrode material is designed to endow LiMn₂O₄ with higher lithium extraction capacity and cycling stability. The SnO₂ nanoparticle islands effectively mitigate stress during the charge–discharge process of LiMn₂O₄, thereby enhancing cycling stability and promoting the diffusion of Li⁺. The lithium adsorption capacity of the LiMn₂O₄ electrode material modified with SnO₂ nanoparticles reaches 19.76 mg g⁻¹ within 1 hour, which is 1.7 times higher than that of LiMn₂O₄ (11.45 mg g⁻¹). The LiMn₂O₄ electrode material modified with SnO₂ nanoparticles shows good selectivity and cycling stability for the separation of lithium ions.