US Patent 7531155 - Silicon powder to nanoparticle conversion

http://www.freepatentsonline.com/7531155.html

This patent from Applied Nanotech teaches a high yield silicon nanoparticle production method based on ultrasonic agitation. Claim 1 reads:

1. A method of making silicon nanoparticles comprising:

a) providing porous silicon powder; and

b) ultrasonically agitating said powder in a solvent to break up porous outermost layers of silicon particles comprising said powder to provide for a dispersion of silicon nanoparticles in said solvent.