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.

中文翻译：

---

用于高流量空气净化和 AI 辅助呼吸诊断的自晶体驻极体聚乳酸纳米纤维


颗粒物 （PM） 是空气中的主要污染物之一，继续严重威胁着人类健康和环境。在这里，开发了一种自晶体诱导驻极体增强 （SCIEE） 策略，以促进静电纺丝聚乳 _L 酸 （PLLA） 纳米纤维的原位驻极体效应和极化特性。该策略特别涉及具有均匀尺寸 （~300nm） 的立体复合体晶体 （SCs） 的精细预构建，这些晶体作为高密度的驻极体和物理交联点被引入 PLLA 静电纺丝溶液中。它能够直接制造自晶体驻极体聚乳酸 （SCE-PLA） 纳米纤维膜 （NFM），有效调节纳米纤维形态，增强电活性相（β相、SCs 和界面域）的产生，协同促进介电常数 （2.48）、表面电位 （4.60kV） 和电荷再生性能（摩擦-输出电压高达 37.60V）的显着增加。这允许对 PM 的物理拦截和静电吸附进行多项改进，例如以超低空气阻力（94.91Pa，32L/min）有效去除 PM _0.3 和 PM _2.5 （94.91% 和 99.15%），与纯 PLA 对应物（82.66% 和 80.98%）形成鲜明对比。鉴于大量电荷的可持续再生，SCE-PLA NFM 即使在密集的吸气和呼气气流 （120 和 100L/min） 下也表现出长期的驻极体效应和 PM _0.3 去除 （92.53%）。此外，电活性 SCE-PLA NMM 已准备好实现呼吸模式的高精度监测 （99.23%）。 我们的 SCIEE 策略为制造具有卓越原位驻极体效应和电荷再生能力的环保纳米纤维开辟了一条有前途的途径，适用于空气净化和被动监测。