Refractive index investigations of nanoparticles dispersed in water

The refractive index of nanoparticles dispersed in water is measured, using the total internal reflection method. The critical angle is determined by the disappearance of diffraction orders from a metal grating. The investigated nanoparticles are titanium dioxide (anatase phase), (35 nm diameter), zinc oxide, (<50 nm diameter), zirconium dioxide, (<100 nm diameter). The refractive index is measured with the experimental uncertainty of 1%. The Lorentz-Lorenz, Maxwell Garnett and Bruggeman relations are applied in the nanoparticle’s refractive indices calculations.