Research of electret air filter: A review

Abstract The harmful effects of air pollution on humans are multifaceted and are closely linked to outbreaks of various infectious viruses. Thus, design of high‐performance air filters that are lightweight, flexible, and easy to prepare is urgent. The electret air filter can utilize the electrostatic force of charge to capture dust particles, making it efficient and convenient, which is highly favored by people. In this study, a summary of the research on electret filters for highly efficient air purification is presented. First, this study outlines the mechanisms of air filtration methods and discusses three factors that evaluate filter performance. The methods of manufacturing electret air filters are then presented, and the advantages and limitations of different methods are discussed. Then, electrification, including corona discharge, friction electrification, electrospinning, thermal electrification, and water electrification as methods, enhances the physical charge adsorption performance of materials, while the use of fluorinate polymer, non‐fluorinate polymer, and biobased polymer as functional substrates exhibits varying degrees of electrification effects. Different materials and manufacturing techniques give the filters additional advantages, such as being self‐degradable and antibacterial. Finally, the challenges that remain in the development of electret filters for use in air purification are also discussed in terms of material type and fabrication technology. It is expected that highly efficient air purification with low energy consumption can be achieved by electret filters with multifunctional capabilities.