MgSc₂Se₄ Solid Electrolyte for Rechargeable Mg Batteries: An Electric Field-Assisted All-Solid-State Synthesis

Magnesium scandium chalcogenide spinels are an important class of materials in Mg anode-based batteries for energy storage applications. The applications of these intriguing materials are not limited to the energy storage, but the use of these materials may also be useful in solar cells, owing to the material optical bandgap. So far, all reported synthetic routes for these spinels involve high-temperature furnace treatment. Herein, a process which involves a facile electric field-assisted synthesis of MgSc₂Se₄ is reported on, yielding after a very short thermal treatment, a material possessing a low room-temperature electronic conductivity of ≈10⁻¹¹ S cm⁻¹, and a room-temperature Mg-ion conductivity of 1.78 × 10⁻⁵ S cm⁻¹. The crucial role of extra selenium on the material electronic conductivity is discussed and explained in detail.