Synthesis of aluminum oxide nanoparticles by laser ablation in liquids

Spherical aluminum oxide (gamma-phase) nanoparticles with sizes below 30 nm were synthesized by pulsed laser ablation in liquids. The wavelength and energy fluence of the nanosecond laser were set at 1064 nm and similar to 1x10(3) J/cm(2), respectively. The optimal repetition rate to maximize the production of those nanoparticles was determined to be at 2,129 +/- 64 Hz. Therefore, the lifetime of the cavitation bubble was estimated to be around 0.47 +/- 0.01 ms.