Biodegradable MOFilters for Effective Air Filtration and Sterilization by Coupling MOF Functionalization and Mechanical Polarization of Fibrous Poly(lactic acid)

• High-performance air filtration materials are importantfor addressingthe airborne pollutants. Herein, we propose an unprecedented accessto biodegradable poly-(lactic acid) (PLA)-based MOFilters with excellentfiltering performance and antibacterial activity. The fabricationinvolved a stepwise in situ growth of zeolitic imidazolate framework-8(ZIF-8) crystals at the surface of microfibrous PLA membranes, followedby mechanical polarization under high pressure and low temperature(5 MPa, 40 degrees C) to trigger the ordered alignment of dipoles inPLA chains and ZIF-8. The unique structural features allowed thesePLA-based MOFilters to achieve an exceptional combination of excellenttensile properties, high dielectric constant (up to 2.4 F/m), andenhanced surface potential as high as 4 kV. Arising from the remarkablesurface activity and electrostatic adsorption effect, a significantincrease (from over 12% to nearly 20%) in PM0.3 filtrationefficiency was observed for the PLA-based MOFilters compared to thatof pure PLA counterparts, with weak relation to the airflow velocities(10-85 L/min). Moreover, the air resistance was controlledat a considerably low level for all the MOFilters, that is, below183 Pa even at 85 L/min. It is worth noting that distinct antibacterialproperties were achieved for the MOFilters, as illustrated by theinhibitive rates of 87 and 100% against Escherichiacoli and Staphylococcus aureus, respectively. The proposed concept of PLA-based MOFilters offersunprecedented multifunction integration, which may fuel the developmentof biodegradable versatile filters with high capturing and antibacterialperformances yet desirable manufacturing feasibility.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Materialteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering (hsv//eng)

Keyword

poly(lactic acid)

MOF functionalization

mechanicalpolarization

air filtration

antibacterial properties

Publication and Content Type

ref (subject category)

art (subject category)