An all-solid-state photo-rechargeable battery based on Cs₃Bi₂I₉

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Development of sustainable energy storage solutions is crucial.
• Perovskite materials offer promising optoelectronic properties.
• Bismuth-based compounds are explored as alternatives to lead-based materials.

Purpose of the Study:

• To present a novel two-electrode photo-rechargeable system.
• To utilize lead-free perovskite Cs3Bi2I9 for combined photoelectric conversion and energy storage.
• To demonstrate a battery system based on bismuth redox chemistry.

Main Methods:

• Fabrication of a FTO/TiO2/Cs3Bi2I9/Pt/FTO device.
• Investigation of the photoactive properties of Cs3Bi2I9.
• Characterization of the battery's charging and discharging performance.
• Testing the system's ability to power an LED.

Main Results:

• The photo-rechargeable system successfully integrated photoelectric conversion and energy storage.
• The Cs3Bi2I9 perovskite demonstrated photoactivity and electrochemical storage capabilities.
• The fabricated battery exhibited an open-circuit voltage of ~0.28 V in the dark after photo-charging.
• A series-connected pack of these batteries powered an LED for tens of seconds in the dark.

Conclusions:

• This work presents the first battery system utilizing bismuth redox chemistry for charging and discharging.
• The lead-free perovskite Cs3Bi2I9 shows potential as a photoactive material for integrated energy conversion and storage.
• The developed system offers a glimpse into self-rechargeable power sources for low-power electronic devices.