Synthesis and Characterization of Photocatalytic Fibers by the Controlled Growth of Column-Shaped Nanotitanosilicate

Seok Ho Jeon and Tai Gyu Lee. Chemical Engineering, Yonsei Univeristy, 134 Sinchon-dong, Seodaemun-gu, Seoul, 120-749, South Korea

Column shaped nanotitanosilicate was successfully prepared by diffusion reactor with the mixture of titanium tetra-isopropoxide (TTIP) and tetraethoxysilane (TEOS). It consists of a diffusion flame reactor with a precursor feed system consisting of a bubbler. The precursor (silica and titania coating solution) was entrained in the gas stream and introduced into the flame (LPG air/oxygen/nitrogen). Also substrates were rotated because of their durability. The photocatalytic activities of nanotitanosilicate obtained by variations of several parameters such as different ratios (wt%) of TTIP to TEOS (12:1, 10:1, 4:1 and 2:1) and three kinds of carrier gas (air, nitrogen and argon) were estimated by the photodecomposition of mercury removal. The morphology, the crystal form, the components, and the functional groups of column shaped nanotitanosilicate were confirmed by FE-SEM, XRD or Raman, FT-IR, respectively. Column shaped nanotitanosilicate was tested for their photocatalytic ability to remove/oxidize vapor-phase elemental mercury. Under UV black light, the Hg0 removal efficiencies were 77.6, 86.2, and 84.5% for air, N2, and Ar, respectively. In case of air, the value was close to 90% even under household fluorescent light. The Hg removal efficiency by nanotitanosilcate was measured under fluorescent light, UV black light, and sun light.