Elucidating the structural and spectroscopic attributes of titania-iron oxide (TiO2-([formula omitted]-Fe2O3)) nanocomposites: Showcasing a pulsed laser ablation in liquid approach

Abstract

Various nanomaterials with tailored photo-electrochemical and physicochemical attributes became viable for the photo-catalysis and sensors applications. Thus, some new types of TiO2-(α-Fe2O3) nanocomposites were made via the pulse laser ablation in liquid method. These nanocomposites at each value of laser fluence were obtained by mixing the colloidal TiO2 nanoparticles and colloidal (α-Fe2O3) nanoparticles at equal ratio. The stability, structures, morphologies, and optical characteristics of the produced nanocomposites (suspended in deionized water) were customized by changing the laser fluence from 3.5–17.7 J cm−2. The high-resolution transmission electron microscopy micrographs showed the existence of homogeneous dispersion of spherical nanocrystallites (mean diameter 12.4 ± 6.0 nm) in the colloidal suspension. Both X-ray diffraction and Fourier transform infrared profiles of the specimen verified their purity and good nanocrystallinity. Two optical absorption peaks were probed in the range of 240 to 380 nm convoyed by a blue-shift. The spectral edge related to UV–Vis absorption was used to estimate the optical band gap of these nanocomposites. TiO2-(α-Fe2O3) nanocomposites made at optimum laser fluence (10.6 J cm−2) exhibited strong fluorescence with the life time decay of 3.64 μs, indicating the electronic density of states modification due to quantum size effects. The presence of Fe, Ti, and O in the X-ray photoelectron spectroscopy spectra reaffirmed the samples purity. The measured strong negative zeta potential (-33.1 mV) of the optimum TiO2-(α-Fe2O3) nanocomposites confirmed their excellent stability in the colloidal suspension. In short, these nanocomposites may be advantageous as good photo-catalysts for waste water treatment and photo-electrochemical uses.