Effects of Ultrasound Exposure Time on Nanometer-Sized Diamond Particles Dispersion

We investigated the improvement in the dispersion of nanometer-sized diamond particles by change of ultrasound exposure time. As the results, the dispersion of the diamond particles improved with increasing ultrasound exposure time. The average particle size of the diamond particles of 5 mu m decreased to less than 100 nm at ultrasound exposure times of 300 and 1200 s. Also, the diamond particles at 300 and 1200 s had a narrow particle size distribution in the nanometer range. The zeta potential on the diamond particles increased to about 30 mV at an ultrasound exposure time longer than 900 s. (c) 2009 The Japan Society of Applied Physics