Microstructural study of a nanocrystalline oxide to be used for resistivity gas sensors

BIANCHETTI, M.F; ARRIETA C.L.; WALSÖE DE RECA N.E.

Buenos Aires

Congreso; 15th International Meeting of Chemical Sensors; 2014

National Atomic Energy Comision of Argentina (CNEA) and Ministry of Science, Technology and Productive Innovation of Argentina (MINCyT)

Nanocrystalline pure and doped SNO2 has been intensively studied for a long time to build resistive gas sensors being still useful to synthesize their powders with the smallest crystllite size. A modified gel-combustion method and a novel reactive oxidation process were proposed for nanopowders synthesis and results were compared. Characterization methods were XRD, Scherrer equation to evaluate the crystallite size, BET absorption to determine specific area and HRTEM to observe the particles, evaluation their mean crystallite size and distribution , defects and effect of calcination treatments. Previous studies showed that if nano-SnO2 replaced the conventional microcrystalline-SnO2 to build resistive gas sensors, sensitivity increased (>30%) and the operation temperature considerably decreased. A heating and measuring system for sensors was also designed and described.