LAUSR

Abstract Conventional electrospinning, along with a fiber accumulation mode parallel to the collector, results in 2D compact structures with limited performance. Fluffing the fiber membranes can enhance their functional performance, e.g., filtration performance (high filtration efficiency but lower airflow resistance), by means of enlarging both the pores and surface area. In this study, without additional instrumental design or any post-treatment, we report a quasi-3D and highly fluffy protein fiber membrane with high filtration performance by applying interface-tailored forces. Via the design of a cooperative collector for generating dual interfacial forces and the manipulation of the surface charges and polarities of protein by different surfactants, a competition between the interfacial forces is achieved. It is found that only with the least polarity and the most charges from protein can a strong repulsion force be generated. The protein fibers, being in-situ repulsed, deposit along with quasi-3D directions, leading to extremely fluffy structures. Compared with a compact protein fiber membrane, the properly fluffed protein fiber membrane exhibits reduced airflow resistance by 11.5 Pa while a higher removal efficiency is acquired. This work deepens the understanding of the interfacial impact on fiber deposition and provides an enlightening strategy to fabricating 3D fiber membranes.