ORIGINAL PAPER UV-protection and photocatalytic properties of electrospun polyacrylonitrile nanofibrous mats coated with TiO 2 nanofilm via sol–gel Saeed Dadvar • Hossein Tavanai • Hamid Dadvar • Mohammad Morshed • Farhad E. Ghodsi Received: 19 February 2011 / Accepted: 13 May 2011 Ó Springer Science+Business Media, LLC 2011 Abstract UV radiation causes serious damage to skin, and a protective system capable of absorbing or reflecting UV radiation is required to protect skin. This paper describes the UV protection and photocatalytic properties of TiO 2 nanofilm coated electrospun polyacrylonitrile (PAN) nanofibrous mats with various nanofiber diameter and area density. The mats were coated by sol–gel process. The results of this research showed that sol–gel is capable of coating porous nanofibrous mats with a weight increase as low as 0.8%. The TiO 2 nanofilm coated on the nanofi- brous mats has a considerable effect on its UV protection. The UV protection factor (UPF) of the mats increases with decreasing nanofiber diameter. In fact decreasing the diameter of nanofibers of the TiO 2 nanofilm coated PAN nanofibrous mats increases their photocatalytic activity. Moreover, this research showed that TiO 2 nanofilm pro- duced through sol–gel process on the PAN nanofibers has a crystalline structure. The UPF of the nanofibrous mat coated with a TiO 2 nanofilm via sol–gel process can be classified as excellent. Keywords Photocatalytic properties  UV-protection  Electrospinning  PAN nanofibrous mats  TiO 2 nanofilm  Sol–gel 1 Introduction Depending on the wavelength, sunlight ultra violet (UV) radiation has been divided into UV-A (315–400 nm), UV- B (280–315 nm), and UV-C (200–280 nm). Prolonged exposure to UV-B radiation is known to cause serious skin damages [1–4]. Effective protection of skin from the consequences of excessive exposure to sunlight needs a protective system capable of absorbing or reflecting UV radiation before reaching the skin surface. Usually, the protection offered by normal clothing is inadequate to protect skin from UV radiation damage [5, 6]. Therefore, attempts have been made to modify textiles in order to increase their protection effectiveness against UV radiation. Finishing of textiles by conventional UV absorbers like phenyltriazines, phenyl salicylates, benzophenones, benzotriazoles, cyanoacrylates, benzotriazoles, and oxalic acid dianilides via exhaustion has major limitations such as toxicity, poor activity, and weak washing fastness [7]. Metal oxide nanoparticles especially TiO 2 and ZnO have also been added to textiles via exhaustion [8, 9] or electrospinning [10, 11] to confer UV-protection to them. It is worth mentioning that other techniques including electron-beam evaporation [12], reactive magnetron sput- tering [13], chemical vapor deposition with or without plasma treatments [14], and sol–gel [15] have been employed in order to deposit metal oxide semiconductor materials particularly TiO 2 on different substrates such as soda-lime [16], mica [17], steel [18], and fibers [19]. TiO 2 which is an important inorganic functional material with high dielectric constant and wide band gap energy of 3.2 eV, is suitable for applications such as UV absorber [20]. Moreover, thanks to their photocatalytic potential, they can also decompose inorganic impurities S. Dadvar  H. Tavanai (&)  M. Morshed Department of Textile Engineering, Center of Excellence in Applied Nanotechnology, Isfahan University of Technology, 84156-83111 Isfahan, Iran e-mail: tavanai@cc.iut.ac.ir H. Dadvar  F. E. Ghodsi Department of Physics, Faculty of Science, The Guilan University, 41335-1914 Rasht, Iran 123 J Sol-Gel Sci Technol DOI 10.1007/s10971-011-2495-7