Surface modification of nanoparticles by mechanical milling with glow discharge

This chapter discusses the surface modification of nanoparticles by mechanical milling with glow discharge. A new mechanical milling device with glow discharge is developed for aiming of surface modification of nanoparticles without heating. The configuration of this device is based on that of Mechanofusion system, which consists of a rotating chamber and an arm fixed with a certain clearance against the inside wall of the chamber. By applying an electric power into the clearance under controlled ambient and rotating chamber, any particles can be subjected to mechanical forces such as compression and shearing, in glow discharge. Using this device, TiO₂ nanoparticle is processed under a gas pressure of 50 Pascals (Pa) of argon (Ar) with 10% ammonia (NH₃₎. TEM-EELS spectrums of the particles indicated that the mechanical milling with glow discharge can promote effective solid-gas reaction without heating. The availability of a novel class of nanoparticles with properties determined by the y high surface/volume ratio offers the possibility of applications ranging from the field of catalysis to the fabrication of photonic materials or devices.