Since airborne fungi have been known to aggravate indoor air quality, studies on developing anti-fungal filters increase recently. In this study, silver (Ag) nanoparticle was selected as anti-fungal agent. HEPA filter was coated with silver nanoparticles which were generated via spark discharge system operating at atmospheric pressure and temperature. The anti-fungal effect of the Ag-filter was evaluated with the conventional culture assay. When the number of Ag nano particle per a fungal particle in the filter was 1.91X106, the fungicidal efficiency was higher than 99%. As another anti-fungal test, ATP bioluminiscence detection method was also carried out and the results were correlated with those of the culture assay.
This paper presents a novel single-step method to prepare the Ag nanometallic particle dispersed fluid (nanofluid) by electrical explosion of wire in liquid, deionized water (DI water). X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) were used to investigate the characteristics of the Ag nanofluids. Zeta potential was also used to measure the dispersion properties of the as-prepared Ag nanofluid. Pure Ag phase was detected in the nanofluids using water. FE-SEM analysis shows that the size of the particles formed in DI water was about 88 nm and Zeta potential value was about -43.68 without any physical and chemical treatments. Thermal conductivity of the as-prepared Ag particle dispersed nanofluid shows much higher value than that of pure DI water.
Functional nanomaterial is expected to have improved capacities on various fields. Especially, metal nanoparticles dispersed in polymer matrix and metal nanofiber, one of the functional nanomaterials, are able to achieve improvement of property in the electric and other related fields. In this study, the fabrication of metal (Ag) nanoparticle dispersed nanofibers were attempted. The Ag nanoparticle dispersed polymer nanofiber and Ag nanofiber were fabricated by electrospinning method using electric force. First, PVP/ nanofibers were synthesized by electrospinning in voltage with the starting materials (Ag-nitrate) added polymer (PVP; poly (vinylpyrrolidone)). Then Ag nanoparticle dispersed polymer nanofibers were fabricated to reduce hydrogen reduction at for 3hr. And Ag nanofibers were synthesized by the decomposited of PVP at for 3hr. The nanofibers were analyzed by XRD, TGA, FE-SEM and TEM. The experimental results showed that the Ag nanofibers could be applied in many fields as an advanced material.