Fabrication of colored glasses by incorporation of a secondary nanosized phase into a silica green body by means of reactive electrophoretic deposition (REPD)

The fabrication of silica glass by powder technology offers a great variety of advantages. Especially the control of the pore size distribution of the green body is important as it is the base for the incorporation of secondary nanosized phases. An application example is the fabrication of a gold ruby glass. Herein, the coloring mechanism is based on light waves being scattered on incorporated gold colloids (Mie scattering). Traditional fabrication methods are mostly multi-step processes where a green body is e.g. soaked with an AuCl 3 solution and sintered afterwards so that the gold colloids are formed. In this paper, the fabrication of a colored silica glass by Reactive Electrophoretic Deposition (REPD) is presented. As the suspension is doped with AuCl 3 , the gold ions are adsorbed on the surface of the silica nanoparticles and are directly incorporated into the green body during the deposition process whereby it is possible to achieve homogeneous samples in a single-step process.