Multi-channel functionalized nanofiber membranes with high mechanical strength for formaldehyde degradation, air purification, and dye degradation.

Nanofiber membranes are considered to be one of the potential materials for air and water purification. Nevertheless, their relatively weak mechanical properties not only limit functional modification but also compromise long-term durability. In this study, the multifunctional tubular nanofiber membrane was specifically developed for indoor air purification and water purification. The resulting tubular nanofiber membrane exhibited exceptional tensile strength (>570 MPa) and high packing density. Through mussel-inspired surface modification and blending methods, manganese dioxide (MnO2) nanoparticles was incorporated into the nanofiber membrane. The effects of potassium permanganate (KMnO4) concentration and MnO2 content on the performance of nanofiber membrane were investigated. The prepared multi-channel functionalized nanofiber air filters (MNAF) exhibit a PM2.5 (particulate matter with diameters less than 2.5μm) filtration efficiency of 96.5 % and a pressure drop of 106 Pa. The high packing density provided a large surface area, increasing the probability of formaldehyde (HCHO) contact with MnO2, which led to an HCHO removal efficiency of 97.3 % within 2 h. At the same time, the material exhibits antibacterial activity against E. coli and S. aureus. Furthermore, the effective degradation of Rhodamine B (RhB) can be achieved in the presence of hydrogen peroxide (H2O2) under a dynamic degradation process due to the excellent mechanical properties of the MNAF. This work offered a novelty approach to fabricating novel functionalized nanofiber materials for indoor air purification and dye degradation.