Coffee waste-derived one-step synthesis of a composite structure with Ge nanoparticles surrounded by amorphous carbon for Li-ion batteries

Abstract

Germanium with a high specific capacity is a promising anode material for Li-ion batteries; However, critical issues such as the pulverization of the electrode during cycling and high cost are yet to be addressed. In this study, we fabricated a composite (Ge/C) consisted of Ge and C using a coffee waste-derived one-step synthesis with GeO2. Ge/C exhibited an improved electrochemical performance, with a discharge capacity of similar to 465 mAh g(-1) at a current density of 100 mA g(-1) and retention of similar to 96% after 100 cycles, compared to those of a Ge/GeO2 sample prepared by GeO2 under the same heating conditions as those for Ge/C. The enhanced performance of the Ge/C anode may be attributed to the improved electronic and ionic motions in the anode, as a result of the amorphous conductive carbon phase adjacent to the Ge active material. (C) 2021 Elsevier B.V. All rights reserved.