Enhancement of the performance of Ge–air batteries under high temperatures using conductive MOF-modified Ge anodes

Abstract

Germanium (Ge)–air batteries have gained significant attention from researchers owing to their high power density and excellent safety. However, self-corrosion and surface passivation issues of Ge anode limit the development of high-performance Ge–air batteries. In this study, conductive metal-organic framework (MOF) Ni₃(HITP)₂ material was synthesized by the gas–liquid interface approach. The Ni₃(HITP)₂ material was deposited on the surface of the Ge anode to prevent corrosion and passivation reactions inside the battery. At 16°C, the discharge time of Ge anodes protected with MOFs was extended to 59 h at 195 µA cm^–2, which was twice that of bare Ge anodes. The positive effect of MOFs on Ge–air batteries at high temperatures was observed for the first time. The Ge@Ni₃(HITP)₂ anodes discharged over 600 h at 65.0 µA cm^–2. The experimental results confirmed that the two-dimensional conductive MOF material effectively suppressed the self-corrosion and passivation on Ge anodes. This work provides new ideas for improving the performance of batteries in extreme environments and a new strategy for anode protection in air batteries.

Keywords

conductive metal-organic frameworks / corrosion / Ge–air batteries / high temperature / passivation