Reusable and Transparent Impaction-Based Filter with Micro Apertured Multiscale Polymeric Stencil for Particulate Matter Capture

Air pollution by particulate matter (PM) in the air including PM1.0, PM2.5, and PM10, which are categorized by particle size, is a critical global environmental issue, harming the climate, ecosystems, and human health. Especially, ultrafine dust including PM1.0 and PM2.5 poses significant human health risks. Commercial fabric-based filters effectively trap PMs but cause high-pressure drop and limited filter capacity and reusability. Electrospun nanofiber filters address some issues but have low mechanical strength, toxic exposure risks, long fabrication times, and restrained reusability. Herein, a reusable and transparent impaction-based PM filter using a UV-curable polymeric stencil with micro apertures is proposed. The polymeric stencil filters achieve high filter efficiency (68-94%), superior filter capacity, and low-pressure drop (<64 Pa). The polymeric stencil filters can be easily cleaned with water or ethanol and remain stable under extreme temperatures (-196 to 450 degrees C) with slight shrinkage (0-7%). The polymeric stencil filters can be broadly utilized for not only industrial, indoor, and vehicle filters but also transparent and flexible facial health masks.