A Study upo n the modern Fabrication M ethod by means of TiO۲/PbO۲ N anofibers via Elect rospinnin g

In this letter, we report a new method to fabricate side -by-side Ti O۲ /PbO۲ nanofibers using the DOSE (dual- opp osite-spinneret electrospinning). Electrospinnin g, regarded as a simple, low-cost, a nd universal technique for fabricating submicro fibers and n anofibers, h as been rec eiving more and more attention over the last ۱۵ years. In ad dition to general bead ed and nonbeaded thin nanofibers, other types of nanofibe rs with int eresting morphology, such as core -shell nanofibers, hollow nanofibers, and side-by-side nanofibers, have been produced by electr ospinning[۱,۲]. A side-by-side structure allows both parts of the nanofib ers to be exposed to the surface. Bicomponent side-by-side TiO۲ /PbO۲ nanofib er photocatalysts have been fabricated via side-by-side electro- spinning [۲]. The ir study demonstrated that the photocat-alytic degradation rate of Rhodamine B (R hB) dye on the side-by-side TiO۲ / PbO۲ nanofibers was m ore than double that on the pure TiO۲ nanofibers. In th is research, We know very well t hat Thin-film heterojunctions and particle heterojunctions have been fabricated via various methods: Kanai et al. deposited PbO۲ /TiO۲ (TiO۲ o vercoated with PbO۲ ) thin- film stacks by r eactive DC magnetron sputtering, and Tada et al. produced patterned bilayer of TiO۲ / PbO۲ (PbO۲ overcoated with TiO۲ stripes) us ing modified sol-gel method. One point to note is that these films were coated on substrates; thus, the photocataly st lost appro ximately half of the contact surfa ce between itself and reactants,wh ich decreased the photo catalytic efficiency. On the other hand, coupled and capp ed semiconductor parti cles may expose more surfaces to reactants, but it is difficult to separate powd er photocatalysts from the solution after photocatalytic rea ction. Ther efore, nanofibers would be an appropriate struct ure for fabricating a ty pe of photo catalyst with a large sur face area exposed to reactants while maintain- i ng good rec overability. In addition to general beaded and nonbeade d thin nanofibers, other types of nanofibers with inter esting morp hology, such as core -shell nanofibers, hollow nanofib ers, and side-by-side nanofibers, have bee n produced by electr ospinning. A side-by-si de structure allows both parts of th e nanofibers to be exposed to the s urface. Bico mponent side-by-side TiO۲ /PbO۲ nanofib er photocatalysts have been fabricated via side-by-side ele ctro- spinni ng [۱,۲]. Their study de monstrated that the photocat-alytic degradation rate of Rhodamine B (RhB) dye on t he side-by-side TiO۲ /PbO۲ nanofibers was more than do uble that on the pure TiO۲ nanofibers.

کلیدواژه ها:

nanofibers ، electr ospinning ، photocatalysts ، fabrication