Fabrication, characterization and n-propanol sensing properties of perovskite-type ZnSnO3 nanospheres based gas sensor

ZnSnO3 nanospheres assembled by numerous thin triangular nanosheets were successfully synthesized by a facile co-precipitation method. The structure and morphology of ZnSnO3 nanospheres were characterized by means of SEM, XRD, TEM and XPS. It showed that ZnSnO3 nanospheres with perovskite structure were approximately 500 nm in diameter and densely packed by many triangular nanosheets. Zn, Sn and O elements were uniformly distributed in the obtained nanospheres. Gas sensing measurements indicated that ZnSnO3 nanospheres with n-type semiconductor characteristics showed fast response, good reversibility, high selectivity and repeatability to n-propanol gas at evaluated operating temperature. The peak response of the gas sensor based on ZnSnO3 nanospheres to n-propanol gas was obtained at an operating temperature of 200 degrees C. Especially, the detection limit of ZnSnO3 nanospheres to 500 ppb n-propanol gas could reach 1.7. The gas sensing mechanism was discussed and explained by the electron depletion theory and oxygen vacancy difference. It indicated that the as-prepared ZnSnO3 nanospheres could be a potential material for fabricating high-performance n-propanol gas sensors.