Thermoplastic Polyurethane-Based Composite Film with a Hierarchical Porous Structure for Radiative Cooling and...

Area of Science:

• Materials Science
• Nanotechnology
• Sustainable Energy

Background:

• Passive radiative cooling (PRC) leverages Earth's atmospheric window to dissipate heat.
• Developing materials with combined cooling and antimicrobial properties is crucial for various applications.

Purpose of the Study:

• To develop a high-performance passive radiative cooling material with integrated antibacterial functionality.
• To evaluate the material's cooling efficiency and its effectiveness in food preservation.

Main Methods:

• Fabrication of a porous thermoplastic polyurethane film doped with MgO (PTM) using a water-solvent phase separation method.
• Characterization of optical properties (solar reflectivity, mid-infrared emissivity) and cooling performance.
• Assessment of antibacterial efficacy against Escherichia coli and application in strawberry preservation.

Main Results:

• The PTM film exhibited high solar reflectivity (94%) and mid-infrared emissivity (0.95).
• Achieved an average cooling effect of 14.6 °C under solar radiation (630 W·m^-2).
• Demonstrated over 95% inhibition rate against Escherichia coli and extended strawberry freshness by 4-8 °C localized cooling.

Conclusions:

• The developed PTM film offers efficient passive radiative cooling and broad-spectrum antibacterial properties.
• The dual-functionality material shows significant potential for zero-energy cooling and enhanced hygiene in food preservation.
• This technology offers a sustainable solution for extending the shelf life of perishable goods.