Diffusion of gold nanoparticles in toluene and water as seen by dynamic light scattering

Although the range of applications for gold nanoparticles (Au NPs) is growing rapidly, the study of the diffusion in different solvents is rare. This paper describes the translational diffusion coefficient of Au NPs inside toluene and water measured by dynamic light scattering. The size of the nanoparticles is examined by transmission electron microscopy and compared with the hydrodynamic radius. The diffusion of the nanoparticles is measured in different angles and temperatures in the two solvents. It is shown that the diffusion measured in both systems obeys Arrhenius relation with the temperature. Although the viscosity of toluene is higher than that of water, the Au NPs are found to diffuse faster in toluene