Influences of Silver-Doping on the Crystal Structure, Morphology and Photocatalytic Activity of TiO2 Nanofibers

Doping of titanium dioxide nanofibers by silver nanoparticles revealed distinct improvement in the photocatalytic activity; however other influences have not been investigated. In this work, effect of sliver-doping on the crystal structure, the nanofibrous morphology as well as the photocatalytic activity of titanium oxide nanofibers has been studied. Silver-doped TiO2 nanofibers having different silver contents were prepared by calcination of electrospun nanofiber mats consisting of silver nitrate, titanium isopropoxide and poly(vinyl acetate) at 600 ̊C. The results affirmed formation of silver-doped TiO2 nanofibers composed of anatase and rutile when the silver nitrate content in the original electrospun solution was more than 3 wt%. The rutile phase content was directly proportional with the AgNO3 concentration in the electrospun solution. Negative impact of the silver-doping on the nanofibrous morphology was observed as increase the silver content caused to decrease the aspect ratio, i.e. producing nanorods rather nanofibers. However, silver-doping leads to modify the surface roughness. Study of the photocatalytic degradation of methylene blue dye clarified that increase the silver content strongly enhances the dye oxidation process.