Ge-doped quaternary metallic oxynitrides GaZnON: The high-performance anode material for lithium-ion batteries

Abstract

Although GaZnON, an anion material, is thought to be a good anode candidate for lithium-ion battery (LIB) owning to its superior chemical/structure stabilities and low volume expansions, the wide application of the pristine GaZnON is seriously hindered by the intrinsically tardy charge transfer kinetic. Herein, Ge cation doped GaZnON (Ge-GaZnON) is prepared by a simple solid state reaction method to study the heteroatomic doping regulated lithium-ion storage performance. Ge cation doping is confirmed by the combination of X-Ray Diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS), and so forth. After 200 cycles at 0.1 A g−1, the capacity of the Ge-GaZnON anode reaches up to 805.9 mAh g−1, much higher than the pristine GaZnON anode. Moreover, the reversible capacity is about 263.8 mAh g−1 after 1000 cycles. The Galvanostatic intermittent titration technique (GITT) and ex-situ electrochemical impedance spectroscopy (EIS) analyses reveal that Ge doping makes the lithiation/delithiation processes more stable with lower reaction resistance and faster charge transfer kinetic. The ex-situ analysis (XRD and XPS) reveals the good structural stability and reversibility of the Ge-GaZnON anode. This study provides a new opportunities to design the next-generation metallic oxynitrides-based materials for lithium-ion batteries.