3D ordered macroporous germanium fabricated by electrodeposition from an ionic liquid and its lithium storage properties

Abstract

Among the group IVA materials, germanium has a large theoretical specific capacity, good electrical conductivity and fast lithium ion diffusivity, making it an alternative anode material for Li ion batteries. Nanostructured electrodes now are the biggest focus to solve the volume expansion problem and to improve cycling and rate performance. Ionic liquid electrodeposition was used to obtain Ge nanoparticles at room temperature, and by combining with a “hard” template, 3D macroporous frameworks have been easily synthesized. 3D ordered macroporous Ge exhibits a reversible capacity of 1024 mA h g⁻¹ and retains a capacity of 844 mA h g⁻¹ after 50 cycles at a rate of 0.2 C.