Effect of deposition pressure on the morphology of TiO₂nanoparticles deposited on Al₂O₃powders by pulsed laser deposition

Abstract

Titanium dioxides nanoparticles coated aluminum oxide powders were fabricated by pulsed laser deposition (PLD) with Nd : YAG laser at 266 nm. The Pulse laser energy is 100 mJ/pulse. During the irradiation of the focused laser on the TiO 2 target, Ar gas is supplied into the chamber. The gas pressure is varied in a range of 1 × 10 −2 to 100 Pa. Titanium dioxides nanoparticles deposited aluminum oxide powders were characterized by using energy dispersive X-ray spectroscopy (EDX), high resolution transmission electron microscopy (HR-TEM), in order to understand the effect of Ar background gas on surface morphology and properties of the powders. The coated TiO 2 nanoparticles had nanosized spherical shape and the crystallite sizes of 10~30 nm. The morphology of coated TiO 2 nanoparticles is not affected by gas pressure. However, the particle size and crystallinity slightly increased with the increase of gas pressure. According to this technique, the size and crystallinity of nanoparticles can be easily controlled by controlling pressure during the laser irradiation.