Synthesis and Photocatalytic Properties of Silver Chloride/Silver Composite Colloidal Particles

AgCl/Ag composite nanoparticles have been synthesized by mechanical activation of reaction NH 4 Cl + AgNO 3 + z NH 4 NO 3 = ( z + 1)NH 4 NO 3 + AgCl using an untargeted reaction product (NH 4 NO 3 ) as a diluent, where z = 7.22 is the dilution parameter, followed by partial photoreduction of AgCl to Ag (Ag + to Ag 0 ). Formation of Ag nanocrystals (about 7 nm in size) on the surface of 40-nm AgCl nanoparticles has been confirmed by X-ray diffraction analysis, transmission electron microscopy, and absorption spectrophotometry in a wavelength range of 200‒1000 nm. Such AgCl/Ag composite particles exhibit high catalytic activity upon the photodegradation of methylene blue dye in aqueous solutions.