Synthesis and Characterization of Metal Oxide Nanoparticles

Abstract

TiO2 nanoparticles were prepd. from titanium isopropoxide in aq. soln., and the particle size and size distribution were detd. as a function of time and temp. We also prepd. ZnO nanoparticles using pptn. from Zn(Ac)2, Zn(ClO4)2 and ZnBr2 in isopropanol. In both cases, nucleation and growth were fast, and coarsening and aggregation were the main factors in detg. the particle size and distribution. We show that coarsening of ZnO and TiO2 nanoparticles follows the Lifshitz-Slyozov-Wagner rate law for diffusion controlled coarsening originally derived for colloidal systems with micron size particles, where the av. particle size cubed is proportional to time. We show that the dominant parameters controlling the coarsening kinetics are solvent, precursor salt, and temp.