Self-crystal electret poly(lactic acid) nanofibers for high-flow air purification and AI-assisted respiratory diagnosis

Cunmin Wang; Long Zhang; Xinjian He; Guiying Zhu; Xinyu Li; Yifan Zhang; Xuanjin Zhu; Heguo Li; Mingming Zhang; Jiefeng Gao; Huan Xu

doi:10.1016/j.jhazmat.2024.136932

Self-crystal electret poly(lactic acid) nanofibers for high-flow air purification and AI-assisted respiratory diagnosis

J Hazard Mater. 2024 Dec 17:485:136932. doi: 10.1016/j.jhazmat.2024.136932. Online ahead of print.

Authors

Cunmin Wang¹, Long Zhang², Xinjian He³, Guiying Zhu⁴, Xinyu Li¹, Yifan Zhang⁴, Xuanjin Zhu⁴, Heguo Li⁵, Mingming Zhang⁶, Jiefeng Gao⁷, Huan Xu⁸

Affiliations

¹ School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, China.
² Hubei Key Laboratory of Automotive Power Train and Electronic Control, School of Automobile Engineering, Hubei University of Automotive Technology, Shiyan 442002, China.
³ School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, China; Jiangsu Engineering Research Center of Dust Control and Occupational Protection, Xuzhou 221008, China. Electronic address: xinjian.he@cumt.edu.cn.
⁴ School of Materials Science and Physics, China University of Mining and Technology, Xuzhou 221116, China.
⁵ State Key Laboratory of NBC Protection for Civilian, Institute of Chemical Defense, Beijing 100191, China.
⁶ China Academy of Safety Science & Technology, Beijing 100012, China.
⁷ School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 272100, China.
⁸ School of Materials Science and Physics, China University of Mining and Technology, Xuzhou 221116, China; Jiangsu Engineering Research Center of Dust Control and Occupational Protection, Xuzhou 221008, China; College of Polymer Science and Engineering, State Key Laboratory of Polymer Materials Engineering, Chengdu 610065, China. Electronic address: hihuan@cumt.edu.cn.

PMID: 39706013
DOI: 10.1016/j.jhazmat.2024.136932

Abstract

Particulate matters (PMs), one of the major airborne pollutants, continue to seriously threaten human health and the environment. Here, a self-crystal-induced electret enhancement (SCIEE) strategy was developed to promote the in-situ electret effect and polarization properties of electrospun poly(L-lactic acid) (PLLA) nanofibers. The strategy specifically involved the elaborate pre-structuring of stereocomplex crystals (SCs) with uniform dimensions (∼300 nm), which were introduced into PLLA electrospinning solution as the electrets and physical cross-linking points of high density. It enabled direct fabrication of self-crystal electret poly(lactic acid) (SCE-PLA) nanofibrous membranes (NFMs), effective regulation of nanofiber morphology, enhanced generation of electroactive phases (β phases, SCs, and interfacial domains), synergistically contributing to remarkable increase of dielectric constant (2.48), surface potential (4.60 kV) and charge regeneration performance (tribo-output voltage as high as 37.60 V). This permitted multiple improvements in physical interception and electrostatic adsorption of PMs, as exemplified by efficient removal of PM_0.3 and PM_2.5 (94.91 % and 99.15 %) with ultralow air resistance (57.2 Pa, 32 L/min), in clear contrast to the pure PLA counterpart (82.66 % and 80.98 %). Given sustainable regeneration of plentiful charges, SCE-PLA NFMs exhibited long-term electret effect and PM_0.3 removal (92.53 %) even at intensive inhalation and exhalation airflow (120 and 100 L/min). Moreover, the electroactive SCE-PLA NFMs were ready to realize high-accuracy monitoring (99.23 %) of the respiratory patterns. Our SCIEE strategy opens up a promising pathway to fabricate ecofriendly nanofibers featuring superior in-situ electret effect and charge regeneration capability, appealing for air purification and passive monitoring.

Keywords: Air filtration; Charge regeneration; Ecofriendly nanofibrous membranes; Electret effect; Passive monitoring; Poly(lactic acid).