Measurement of diffusivity of nanometer material by means of laser photothermal displacement technique

A method for measuring diffusivity of nanometer material by means of laser photothermal displacement technique is presented,which measures the phase of thermal displacement in different frequencies and gives the diffusivity of material by fitted curves of phase.Experimental results of the diffusivity of nanometer TiO2 at different annealing temperatures are given and the results indicate that the diffusivity of nanometer TiO2 decreases while the annealing temperature rises.