Using a Battery to Synthesize New Vanadium Oxides

International audience; Sodium electrochemical deintercalation in a battery was used as a route to synthesize new vanadium oxides. Sodium layered oxides were used as positive electrode materials in batteries and sodium was electrochemically deintercalated up to a precise composition resulting in the discovery of a new phase Na1/2VO2. As for many vanadium oxides, this compound presents a magnetic transition, slightly above room temperature, around 325 K, as well as a structural transition involving displacements of vanadium ions. The discovery of this new vanadium oxide and the study of its unique electronic properties have only been possible because the battery permits the synthesis of this new phase at room temperature. This shows that many more new systems could be explored using electrochemical (de)intercalation in a battery and new materials that would be impossible to synthesize by classical solid state reaction could be obtained.