Are aluminium titanate-based nanostructures new photocatalytic materials? Possibilities and perspectives

Abstract

Nanostructured aluminum titanate (AT) was synthesized by the sol-gel method. The calcination temperature was selected as a processing variable to obtain different phase ratios of AT and its parent phases i.e. TiO2 and Al2O3. The main aim behind the present work was to cast light on the photocatalytic performance of AT-based nanocomposites and evaluate their capability to serve as a novel photocatalyst. X-ray diffraction (XRD) analysis and field-emission scanning electron microscopy (FE-SEM) studies were conducted to evaluate the microstructure-sensitive properties of the synthesized powders. Diffuse reflectance spectroscopy (DRS) and the methylene blue degradation test were carried out to estimate the band gap energy values and amounts of degradation. In addition, the durability and stability of the AT-based nanocomposites were studied by the recycling test. The Brunauer–Emmett–Teller (BET) surface area of the AT-based sample and pure anatase were determined. It was found that AT content in these nanocomposite mixtures can greatly affect the photocatalytic activity. The higher the relative AT content the improved the photocatalytic performance will be, although its surface area was smaller than that of pure anatase. The most effective composition of photocatalyst is roughly pure AT with 56.33% of degradation. For the first time, the present study uncovers a novel material mixture having twice as much photodegradation as anatase. Actually, DRS results introduce the AT-based nanocomposites as semiconductors with Eg=2.89eV, while it was yet known as insulators with about Eg=4.5eV.