A Novel Piezoelectric Nonwoven Fabric for Recoverable High-Efficiency Filters

Area of Science:

• Materials Science
• Environmental Engineering
• Nanotechnology

Background:

• Haze pollution from fine and ultrafine particulate matter (PM) significantly impacts public health.
• Current electrostatic filters face challenges with rechargeability and ozone byproducts, limiting their long-term effectiveness and reusability.
• There is a need for advanced filtration materials that offer high efficiency, stability, and environmental sustainability.

Purpose of the Study:

• To develop a novel electrostatic filter with ultra-high removal efficiency, long-term performance stability, and reusability.
• To investigate the use of piezoelectric lithium niobate (LN) particles integrated into a polypropylene (PP) matrix for air filtration.
• To address the limitations of conventional polymer electret filters.

Main Methods:

• Fabrication of lithium niobate/polypropylene (LN/PP) nonwoven fabric using a melt-blown strategy.
• Integration of piezoelectric LN particles into a PP matrix.
• Evaluation of filtration efficiency for various particulate matter sizes (PM0.3 to PM10).

Main Results:

• The fabricated LN/PP nonwovens demonstrated an ultra-high removal efficiency of 99.9% for PM0.3 to PM10.
• Continuous filtration over 11 days maintained approximately 95% removal efficiency due to sustained piezoelectric charge regeneration.
• The filters retained nearly 90% removal efficiency after eight washing cycles, indicating excellent reusability.

Conclusions:

• The proposed LN/PP nonwoven fabric offers a promising alternative to conventional filters, combining high efficiency with recoverability.
• The piezoelectric nature of LN particles enables self-regeneration of charges, ensuring long-term performance stability.
• This innovative filtration strategy holds potential for reducing plastic pollution and improving air quality.