Preparation and Characterization of the TiO<sub>2</sub> Coated Silk Fibroin Filters

Abstract

The main objectives of this research are the synthesis and characterization of the TiO2 coated silk fiborin filters for indoor air contaminant removal. Silk fibroin was degummed from silk sericin using sunlight soap solutions at 90 °C for 60 mins. Next it was washed with distilled water, reformed into a rectangle shape, and dried at 80 °C for 3 hrs in a vacuum oven. Silk fibroin filters were then coated with TiO2 solution at different dosages and dried in sunlight. Morphological structure of the TiO2 coated silk fiborin filters was analyzed using a scanning electron microscope (SEM). The band gap energies of the filters were measured using a UV/VIS/NIR spectrophotometer. Pressure drop across the filters was also examined using the manometer technique. SEM micrographs revealed the fibrous morphology of the SF fiber. An average diameter of the SF fiber was estimated to be approximately 10 μm. The spectral data recorded from the UV/VIS spectrophotometer showed the strong cut off at 390 nm. Therefore, the band gap engergy can be caculated to be approximately 3.17 eV. From the pressure drop testing, differential pressure of the filters without TiO2 was very small, and it was relatively increased with percent TiO2 coated on the SF filters. However, the differential pressures of the SF filter are less than that of the commercial air filter. The VOCs removal efficiency of the synthesized filters will be further investigated.