Semi-transparent and eco-friendly face masks for PM0.3 filtration via biomimetic-fractal nanofibers

To address the need for sustainable high-performance face masks, we demonstrate a strategy that utilizes zein for efficient nanofabrication. An electrospinning process controllably splits the fluid jet, allowing for the creation of face masks composed of fine, fractal-like nanofibers without the need for impurity excipients. This process, enabled by an dipole-force-induced interfacial fluctuation mechanism that we identified, results in face masks that achieve exceptional air filtration performance, surpassing that of commercial N95 masks, while reducing both weight and thickness by half. The significant reduction in material use grants the face masks high optical transparency, facilitating unobstructed facial recognition. Crucially, the pure zein composition allows for the reprocessing of the face masks, contributing to further resource conservation. This work provides a simple, eco-friendly solution for advanced personal protection and points the way toward sustainable wearable devices. Designing zein-based face air filters are promising, though it is challenging to balance air filtration and optical properties. Here the authors use a jet-splitting method to fabricate a transparent face mask, maintaining air filtration properties.