Amorphous sodium vanadate Na1.5+yVO3, a promising matrix for reversible sodium intercalation

Sodium insertion into the vanadate NaVO3 shows the formation of an amorphous phase with the composition Na1.5 + yVO3. The latter phase exhibits reversible electrochemical sodium intercalation/de-intercalation properties through a solid solution-like process, for 0 < y < 0.7, with redox cycling at 1.8 V vs. Na+/Na and a capacity of 150 mAh/g. This result opens the route to the investigation of amorphous matrices involving transition metal oxides for sodium ion battery applications. (C) 2013 Elsevier B.V. All rights reserved.