Electrochemical sodium storage in amorphous GeOx powder

The amorphous GeOx (x < 1) was synthesized and investigated its suitability as a Na-ion battery anode. GeOx was synthesized by oxidizing Zintl-phase NaGe with isopropyl alcohol at room temperature. The amorphous GeOx showed good electrochemical Na storage as an anode for Na-ion batteries, with first reversible capacity of 342 mAh g−1, high power of 237 mAh g−1 (6 A g−1), and cycle performance, retaining a capacity of 216 mAh g−1 after 40 cycles.