The applications of semiconductor materials in air batteries

Air batteries are promising energy storage technologies that have gained continuous attraction due to their high energy densities. At present, investigations on anodes of air batteries are usually focused on various metals such as Li, Zn, Al. In contrast, the semiconductor anodes like Si and Ge are less investigated. Si-air battery possesses a high theoretical energy density and Ge-air battery has a high actual power density and ideal safety. Besides anodes, air cathodes where oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are also the key components in air batteries. To further promote the discharging performance and facilitate energy conversion/storage, semiconductor materials have been introduced in electrochemical cells like Li-O2 and Zn-air batteries. This review briefly summarizes semiconductor materials utilized in various air batteries, including the progress of Si-air and Ge-air batteries and recent advances in semiconductor cathodes catalysts. Finally, the remaining challenges and further perspective are discussed.