Functional metal oxide nanosystems by a hybrid CVD/sol-gel approach

The present contribution is devoted to outlining some recent results from an innovative approach to metal oxide nanosystems. The proposed synthesis pathway is based on three successive steps: i) preparation of a porous xerogel layer (host) via sol-gel (SG); ii) CVD of a guest phase on the above matrix, making it possible to achieve an intimate host/guest intermixing; iii) ex situ thermal treatment under suitable conditions, aimed at tailoring the system properties as a function of the desired application. In particular, the above route has been adopted in two specific cases, LaCoO3 and CeO2-ZrO2 nanostructured thin films, which are acquiring increasing importance in the development of fuel cell technology. The most significant results, obtained by glancing incidence X-ray diffraction (GIXRD), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and transmission electron microscopy (TEM), will be critically discussed, emphasizing the achievement of tailored material properties by design.