Graphene-coated Ge as anodes in Ge-air batteries with enhanced performance

Ge-air batteries, as a novel kind of semiconductor-air battery, have attracting more attention due to its good safety and ideal kinetic performances. However, Ge-air batteries also suffer from some challenges such as passivation and self-corrosion on Ge anodes during the discharge process. In this work, Ge/graphene composite anode is fabricated via plasma enhanced chemical vapor deposition and the performance of coin-type Ge-air batteries were demonstrated in detail for the first time. Compared with Ge-air batteries prepared with bare Ge anodes, batteries with Ge/graphene anodes exhibit longer discharge time improved by 38.9%-90.3% and pro-vide higher power density. The introduction of graphene enables uniform deposition of GeO2 and alleviate passivation at the interface during the discharge process. Furthermore, the first-principles calculations reveal that the interface coupling of Ge/Graphene inhibits the diffusion of H2O and accumulation of GeO2 clusters onto the anode surface. This study mitigates the passivation and self-corrosion problems of Ge-air batteries by using graphene-coated Ge as anodes and provides new opportunities for the future development of Ge-air batteries.

Automated summary

In this work, Ge/graphene composite anode was fabricated via plasma enhanced chemical vapor deposition and the performance of coin-type Ge-air batteries were demonstrated in detail for the first time. Compared with Ge-air batteries prepared with bare Ge anodes, batteries with Ge/graphene anodes exhibit longer discharge time improved by 38.9%-90.3% and provide higher power density. The introduction of graphene enables uniform deposition of GeO2 and alleviates passivation at the interface during the discharge process.