Organosilica Spheres Covalently Functionalized with Diphenylanthracene and Viologen Units

Organosilica spheres functionalized with two different photoactive units, diphenylanthracene, DPA@SPH, and viologen, VIO@SPH, covalently linked to the silica framework are prepared. These new materials have a uniform diameter, 300 nm for the DPA@SPH and 550 nm for the VIO@SPH, and exhibit the typical photochemical response of the organic moieties. It is observed that organic radical cations incorporated in the structure of the functionalized silica spheres are remarkably persistent. Due to their morphology and regular diameter DPA@SPH do not tend to aggregate and they form a highly regular, ordered and homogeneous multilayer film of high surface coverage which is employed as the active layer for the preparation of an electroluminescence cell.