Ahmad-Fauzi Mohd Noor

Morphological and structural studies of titanate and titania nanostructured materials obtained after heat treatments of hydrothermally produced layered titanate

Different types of titanate and titania nanostructured materials have been successfully synthesised and characterized using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and raman spectroscopy. Elemental analysis was determined by energy dispersive X-ray spectroscopy (EDX) analyzer while thermogravimetric-differential scanning calorimetry (TG-DSC) was used to determine thermal stability. In this study, we found that nanotubes were formed during the washing treatment stage with HCl and distilled water. When the pH of the washing solution was 12, sodium titanate nanotubes were obtained, while when the pH of the washing solution was 7, hydrogen titanate nanotubes were obtained. Sodium titanate nanotubes were thermally stable up to 500°C; however, at 700°C, the nanotubes structure transform to solid nanorods. Meanwhile, hydrogen titanate nanotubes decomposed to produce titania nanotubes after heat treatment at 300°C for 2 hours. At 500°C, the tubular structure broke to small segments due to destruction of the nanotube. Further heat treatment at 700°C, led to the destruction and collapse of the nanotubes structure produce titania nanoparticles.