Porous-alumina-assisted formation of 3-D nanostructured niobium oxide films for advanced sensing applications

Abstract

Here we synthesize a 3-D metal/oxide/metal nanostructured film that merges the benefits of advanced nanocomposite inorganic materials with the flexibility of nonlithographic electrochemical technologies based on so-called porous-anodic-alumina-assisted anodizing of a refractory metal and the point electrodeposition of noble metals. The film is composed of a thin niobium oxide layer with spatially-ordered upright-standing niobium oxide nanocolumns, assembled between the two parallel electrodes, which work as long aspect ratio semiconducting nanochannels whose resistivity is greatly impacted by chemisorption reactions when a gas interacts with the film. A laboratory gas sensor employing the film, assembled on a standard TO-8 Metal Can Package, shows superior characteristics for H2 and especially C2H5OH detection. © 2015 The Authors. Published by Elsevier Ltd.Here we synthesize a 3-D metal/oxide/metal nanostructured film that merges the benefits of advanced nanocomposite inorganic materials with the flexibility of nonlithographic electrochemical technologies based on so-called porous-anodic-alumina-assisted anodizing of a refractory metal and the point electrodeposition of noble metals. The film is composed of a thin niobium oxide layer with spatially-ordered upright-standing niobium oxide nanocolumns, assembled between the two parallel electrodes, which work as long aspect ratio semiconducting nanochannels whose resistivity is greatly impacted by chemisorption reactions when a gas interacts with the film. A laboratory gas sensor employing the film, assembled on a standard TO-8 Metal Can Package, shows superior characteristics for H2 and especially C2H5OH detection. © 2015 The Authors. Published by Elsevier Ltd.