Hybrid ZnO-dye hollow spheres with new optical properties from a self-assembly process based on evans blue dye and cetyltrimethylammonium bromide

Abstract

A facile one-step process for the fabrication of hybrid ZnO-dye hollow spheres with novel optical properties has been discovered. Addition of Evans blue (EB) dye to cetyltrimethylammonium bromide (CTAB) results in the formation of CTAB-EB micelles through an ionic self-assembly process, and the resulting material acts as a soft template for the crystallization of ZnO upon addition of a zinc salt and ammonia under mild refluxing conditions. The formation mechanism of such hollow spheres has been investigated. These new hybrid ZnO-dye hollow spheres display distinct optical properties that differ from properties observed for the pure ZnO and dye components. This approach is a new and effective method for fabricating novel semiconductor-dye hybrids with unique electronic and optical properties and is expected to provide access to additional inorganic-organic materials with novel structures and unusual functionalities. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.