The Influence of silver nanoparticles on TiO2 with alpirin dye: optical and structural study

Abstract

Sol-gel derived Titanium (iv) oxide (TiO₂) was deposited on to substrate glass using the screen printing technique. Silver nanoparticles (AgNPs) were deposited unto the TiO2 samples through the successive ionic layer adsorption and reaction method. The samples were soaked into the novel alpirin and were  investigated. The films were characterized by Surface Profilometry, Ultraviolet –Visible light Spectroscopy (UV-Vis Spec) X-ray Diffraction (XRD) and Energy Dispersive Spectroscopy (EDS). The Surface Profilometry indicates that the samples were thin films. XRD  results showed crystalline structure of titanium dioxide. Crystal phase observed for TiO₂ soaked in alpirin dye and the sample that served as control are anatatase structure. The average crystallite size of titanium dioxide when soaked into Alpirin was found to be  with average dislocation density of  and band gap of 2.52 eV. However, the film with the combination AgNPs + Alpirin, has the average crystallite size of  with average dislocation density of  and the band gap of 2.00 eV as against the pure TiO₂ with average crystalline size of  and average dislocation density of and band gap of 3.65 eV. Optical absorbance for pure TiO₂ was low but increased when soaked with Alpirin and AgNPs + Alpirin. The results showed that all the films have high transmittance within the visible and near infra red region though there was slight decrease when soaked with Alpirin and AgNPs + Alpirin. Absorption coefficient, extinction coefficient and optical conductivity increased on soaking with Alpirin and increased further when soaked with AgNPs + Alpirin. The synergy between AgNPs + Alpirin show that the incorporation of metal nanoparticle is beneficial for enhanced photoactivity. The presence of silver and some other substances in the sample were confirmed through Energy Dispersive x-ray Spectrometry (EDS).