Optical properties of silicon nanoparticles by ultrasound-induced solution method

White-light-emitting silicon nanoparticles, whose surfaces were passivated with butyl, were prepared using a focused ultrasonic energy. The white light was achieved by controlling only the size distribution without adding any fluorescent ions. The white-light-emitting silicon nanoparticles had a wide size distribution of 1-5 nm and an average size of 2.7 nm, which were sufficiently small to indicate the quantum confinement effect for silicon. The photoluminescence spectrum covered a wide range of 320 nm-700 nm with a full width at half maximum of approximately 190 nm.