Ethyl cellulose/gelatin/β–cyclodextrin/curcumin nanofibrous membrane with antibacterial and formaldehyde adsorbable capabilities for lightweight and high–performance air filtration

Functionalization of bio–based nanofibers is the development tendency of high–performance air filter. However, the conventional structural optimization strategy based on high solution conductivity greatly hinders the development of fully bio–based air filter, and not conducive to sustainable development. This work fabricated fully bio–based nanofibrous membrane with formaldehyde–adsorbable and antibacterial capabilities by electrospinning low–conductivity solution for high–performance air filtration and applied to lightweight mask. The “water–like” ethyl cellulose (EC) was selected as the base polymer to “nourish” functional materials of gelatin (GE), β–cyclodextrin (βCD), and curcumin (Cur), thus forming a solution system with high binding energy differences and electrospinning into ultrafine bimodal nanofibers. The filtration efficiency for 0.3 μm NaCl particles, pressure drop, and quality factor were 99.25 %, 53 Pa, and 0.092 Pa−1, respectively; the bacteriostatic rates against Escherichia coli and Staphylococcus aureus were 99.9 % and 99.4 %, respectively; the formaldehyde adsorption capacity was 442 μg/g. This is the first report on antibacterial and formaldehyde–adsorbable high–performance air filter entirely made from bio–based materials. This simple strategy will greatly broaden the selection of materials for preparing high–performance multifunctional air filter, and promote the development of bio–based air filter.