Orthorhombic Pbcn SnO2 nanowires for gas sensing applications

Pure monocrystalline orthorhombic SnO2 nanowires decorated and non-decorated with cassiterite SnO2 nanoclusters are analyzed and compared with pure monocrystalline cassiterite SnO2. We corroborate the coexistence of both, cassiterite and orthorhombic phases, having a higher growth speed for the cassiterite one, in the obtained nanowires by the evaporation/condensation technique. For both phases, the building blocks are the [SnO6]8(-) octahedron which are forming chains of edge-sharing octahedral along the [001] direction for the cassiterite phase, while in the orthorhombic phase, chains run in a zigzag fashion and contains four octahedra on each unit of chain instead of two previously reported for orthorhombic material obtained at high pressure conditions as Pbcn SnO2 orthorhombic structure. Results obtained reveal singular structural characteristics of these synthesized orthorhombic nanowires. (c) 2007 Elsevier B.V. All rights reserved.