Mesoporous germanium nanoparticles synthesized in molten zinc chloride at low temperature as a high-performance anode for lithium-ion batteries.

Abstract

In a simple and convenient way, mesoporous germanium nanoparticles (mp-Ge NPs) are prepared by a "metathesis" reaction of magnesium germanide (Mg2Ge) and zinc chloride (ZnCl2) in an autoclave at 300 °C. Investigated as anode materials for lithium-ion batteries, the prepared mp-Ge NPs exhibit a high capacity retention of 1048 mA h g-1 at 1 C after 1000 cycles and a high rate capacity of 727.1 mA h g-1 at 10 C in Li-Ge half cells. Additionally, a 3.4 V lithium-ion full cell (Ge-LiCoO2) with an energy retention of 85% (∼268.8 W h kg-1) over 100 cycles is achieved.