Fabrication of Spherical-Shaped Submicron Particles of ZnO Using Laser-induced Melting of Submicron-sized Source Materials

Recently, laser irradiation (LI) using non-focused laser beam at moderate fluence for colloidal nanoparticles concentrates much attention as a promising technique to produce spherical submicron-sized particles (SSMPs). In this study, we apply this technique on submicron-sized source particles of ZnO, differing from the previous studies in which nano-sized source particles were used. By using submicron-sized source particles, SSMPs were produced with no additional treatment to remove remaining source nanoparticles. In addition, it was revealed that SSMPs are not produced via simple melting of single source particle, but from agglomerates of the source particles that were formed prior to LI. It was also revealed that additional agglomeration of the SSMPs occurs during LI, resulting in the size increase of SSMPs with increasing laser fluence.