Investigation of germanium selenide electrodes for the integrated photo‐rechargeable battery

Autonomous photo-rechargeable electronic energy storage device has become a new type of solution to the problems of renewable energy fluctuations and storage. The combination of light conversion equipment and energy storage equipment improves the packaging efficiency of the equipment, however how to explore a type of electrode materials for energy collection and storage become a real challenging issue. Here, we try to explore the GeSe nanoparticles as the potential idea electrode for the integrated photo-rechargeable battery. On the one hand, GeSe nanoparticle electrode shows good Li+ storage performances. At the current density of 0.2 A g−1, its reversible capacity is 670 mAh g−1 after 100 cycles. On the other hand, during the photo-voltaic measurement, GeSe electrodes could generate a photocurrent that increases by 8 uA/cm2 under the visible light irradiation in aqueous electrolyte. When LiClO4 in polycarbonate solvent is used as the electrolyte, the electrons move in the reverse direction from the GeSe electrode, form reverse current, reduce Li+ to lithium metal, and finally store light energy into chemical energy in a short time. Considering its presenting behaviors in Li+ storage and photon harvesting, our research proposed the possibility for the application of GeSe materials in the integrated photo-rechargeable batteries.