Fabrication and properties of non-isolating gamma-alumina meso-foam

Films of submicrometric hollow capsules of a metal oxide material have attracted great attention in the field of the inorganic meso-foams. In particular the possibility of changing the characteristics of the bulk metal oxides by tuning the morphology of the inorganic materials at a submicrometric scale has been considered appealing for several applications in optics, catalysis, sensors and magnetism. Here we present a sustainable method for generation of monodisperse meso-foam of gamma-alumina made of aggregates of monodisperse capsules fabricated from aqueous solution and in ambient conditions. The electrical characteristics of the alumina meso-foams are reported and we demonstrate that films obtained by the proposed method show conductivity significantly higher than that found in similar titania systems. These experimental results endorse this new meso-foam as a new "engineered ceramic", suitable for microelectronics and sensor applications. (C) 2016 Elsevier B.V. All rights reserved.