Highly Water-Stable Polymer-Perovskite Nanocomposites

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Hybrid metal-halide perovskite nanocrystals (NCs) exhibit excellent optical properties but suffer from poor stability in humid environments.
• Developing stable perovskite-based materials is crucial for their practical application in electronic devices.

Purpose of the Study:

• To create highly fluorescent and water-resistant lead-halide perovskite (LHP) NCs by embedding them in polymer composites.
• To investigate the impact of different polymers on the optical properties and long-term stability of LHP NCs.

Main Methods:

• Preparation of MAPbBr₃-HDA NCs dispersed in poly(l-lactide) (PLla), polypropylene glycol (PPGly), and polysulfone (PSU) polymers via casting or spin-coating.
• Characterization of fluorescence quantum yield, emission spectra, and time-resolved photoluminescence.
• Assessment of water resistance through immersion tests and evaluation of long-term stability under ambient conditions.

Main Results:

• MAPbBr₃-HDA@PLla suspensions showed a high fluorescence quantum yield of 93%.
• MAPbBr₃-HDA@PPGly/PSU composite films demonstrated stable green fluorescence emission (528 nm) after 18 months of exposure to air and water immersion up to 45 °C.
• The polysulfone (PSU) polymer was identified as key to achieving high water stability by preventing NC degradation.

Conclusions:

• Dispersion of LHP NCs in commodity polymers, particularly PSU, significantly enhances their water resistance and long-term stability.
• These stable LHP NC composites are promising for applications in wearable electronics and other waterproof devices.
• The developed method offers a viable route for fabricating robust perovskite-based optoelectronic materials.