Highly Luminescent Aniline and TiO2 Composite: The Effect of Weight Ratio of Aniline and TiO2

Strong deep ultraviolet emitting aniline and $TiO_2$ composite has been synthesized via hydrolysis and condensation reactions of titaniumisopropoxide ($Ti(OPr)_4$), aniline, and acetic anhydride. Three different weight ratios of aniline and $Ti(OPr)_4$ including 3:1 ($TiO_2An-A$), 2:1 ($TiO_2An-B$), and 1:1 ($TiO_2An-C$) were synthesized and characterized their optical properties. The FTIR spectra of the $TiO_2An-A$, -B, and -C showed the absorption intensities of the benzene ring stretching and bending vibrations, and benzene ring -CH stretching, bending, and deformation vibrations increased with the increase of the amount of aniline. The UV-visible absorption spectra showed that the UV region absorption was slightly increased with the increase of the amount of aniline. The photoluminescence (PL) intensities were exponentially increased with the increase the excitation wavelength from 307 to 317 nm, steadily increased from 300 to 313 nm and slowly increased from 302 to 308 nm for $TiO_2An-A$, -B, and -C, respectively and decreased thereafter. Therefore, the PL intensity is strongly dependent on the weight ratio of $Ti(OPr)_4$ and aniline.