A multifunctional nanofiber composite for air filtration: thermal, electrochemical, and antibacterial characterisation

This study reports the fabrication and comprehensive characterisation of silver nitrate infused electrospun polyvinyl alcohol (PVA) nanofibers for potential use in antimicrobial and air filtration applications. Three formulations were developed by varying concentrations of silver nitrate and zinc oxide, with glyoxal as a cross-linking agent and Triton X-100 as a surfactant. Morphological and physicochemical properties were assessed using SEM, FTIR, XRD, AFM, TGA/DSC, along with functional evaluations including antibacterial activity, electrochemical stability, and scratch-healing behaviour. SEM analysis revealed smooth, bead-free fibres, while FTIR confirmed the incorporation of functional groups due to effective chemical interactions. XRD patterns showed enhanced crystallinity in Sample 2, attributed to optimal dispersion of silver nitrate and ZnO nanoparticles. Among all samples, Sample 2 exhibited the lowest surface roughness (Ra ∼43.89 nm), highest thermal stability, and the largest bacterial inhibition zones (2.0 cm against E. coli and P. aeruginosa). Electrochemical tests showed improved corrosion resistance, and scratch recovery assessments demonstrated visible self-healing after 15 days. Overall, the developed nanofiber membranes exhibit strong potential for use in advanced biomedical and antimicrobial air filtration systems.