Reversible self-powered fluorescent electrochromic windows driven by perovskite solar cells

Area of Science:

• Materials Science
• Renewable Energy
• Optoelectronics

Background:

• Self-powered electrofluorochromic devices (EFCDs) are crucial for energy-efficient smart windows in green buildings.
• Existing EFCDs often require external power sources, limiting their practical application and integration.
• Perovskite solar cells (PSCs) offer efficient solar energy conversion, but their integration with other functional devices needs further exploration.

Purpose of the Study:

• To develop a novel self-powered EFCD system by integrating a perovskite solar cell (PSC) with electrochromic materials.
• To demonstrate the feasibility of using polyoxometalates (POMs) and a fluorescent component in a wet adhesive format for EFCD applications.
• To achieve efficient solar-driven electrochromic switching and reversible fluorescence under UV illumination without external bias.

Main Methods:

• Fabrication of a self-powered EFCD by combining a PSC with a newly developed wet adhesive containing polyoxometalates (POMs) and a fluorescent material.
• Construction of an integrated battery system using POMs and magnesium to power the EFCD's bleaching process.
• Characterization of the EFCD's electrochromic performance (color transition) and fluorescence switching properties under solar and UV light.

Main Results:

• The fabricated EFCD successfully transitioned from white semitransparent to dark blue-tinted without external power, driven by the integrated PSC.
• The device exhibited reversible fluorescence switching between yellow and dark states when exposed to UV light.
• The POMs and magnesium-based battery effectively powered the EFCD's bleaching, enabling rapid coloration upon connection with the PSC.

Conclusions:

• A novel self-powered EFCD has been successfully demonstrated, integrating PSCs with POM-based electrochromic and fluorescent materials.
• This integrated system offers a promising solution for smart windows, enabling tunable transparency and fluorescence with solar energy.
• The developed wet adhesive formulation and battery design pave the way for advanced, self-sufficient optoelectronic devices.