Combating Urban Air Pollution in Indonesia: Recent Advances in Electrospun Nanofiber Membranes for High-Efficiency Particulate Matter Capture

Indonesia faces a severe air pollution crisis, with average PM2.5 concentrations exceeding WHO guidelines by more than sevenfold and contributing to an estimated 13% of annual deaths nationwide. Emerging evidence further links PM2.5 exposure to increased vulnerability to viral infections, including COVID-19 and influenza, compounding the country's public health burden. Conventional personal protective equipment, predominantly petroleum-based polypropylene masks, offers only short-lived electrostatic filtration and generates substantial non-biodegradable waste, undermining both protective efficacy and environmental sustainability. Electrospinning has emerged as a promising alternative, enabling the fabrication of nanofiber membranes with diameters from 10 nm to the submicron scale that achieve high particulate filtration efficiency at low pressure drop through mechanisms including interception, inertial impaction, Brownian diffusion, and electrostatic capture. This review synthesizes recent advances across single- and multi-spinneret fabrication techniques, bead-on-string architectures, and post-treatment strategies for optimizing filtration performance. It further examines the development of biodegradable polymer membranes, upcycled waste-derived nanofibers, and multifunctional designs incorporating antimicrobial, antiviral, and humidity-resistant properties tailored to tropical urban conditions. These innovations collectively achieve filtration efficiencies exceeding 99% while addressing plastic waste accumulation. This review proposes a practical roadmap toward sustainable, multifunctional electrospun membranes capable of mitigating both urban air pollution and airborne pathogen transmission in Indonesia's rapidly urbanizing tropical cities.