One-step method synthesis of cobalt-doped GeZn1.7ON1.8 particle for enhanced lithium-ion storage performance

Abstract

The exploration of alternative anode materials to obtain the satisfactory lithium-ion storage performance is crucial for next-generation energy storage devices. Herein, the rational design of a completely new anode material is reported by a simple solid state reaction method, which follows an insertion-type lithiation mechanism, cobalt-doped GeZn1.7ON1.8 (Co-GeZn1.7ON1.8). The introduced cobalt increases the achievable capacity by more than 100%, originating from the additional space for the lithium-ion insertion. The Co-GeZn1.7ON1.8 particle anode delivered high capacity (861.4 mAh g−1 at 0.1 A g−1 after 200 cycles) and ultralong cycling stability (2000 cycles at 1.0 A g−1 with a maintained capacity of 435 mAh g−1), which represents outstanding comprehensive electrochemical performance. Electrochemical kinetic results confirms the existence of the pseudocapacitive and the reduced lithium-ion diffusion barrier in the Co-GeZn1.7ON1.8 particle anode. Furthermore, ex-situ XRD and XPS analyses corroborate the reversible intercalation electrochemical reaction mechanism of the Co-GeZn1.7ON1.8 anode. This study offers a new vision toward designing high-performance quaternary metallic oxynitrides-based materials for large-scale energy storage applications.