Room temperature synthesis of γ-Fe2O3 by sonochemical route and its response towards butane

Nanocrystalline gamma iron oxide (gamma-Fe2O3) has been synthesized at room temperature through sonication-assisted precipitation technique. The key in obtaining gamma-Fe2O3 at room temperature lies in exploiting high-power ultrasound (600W). The gas-sensing properties to n-butane of pure gamma-Fe2O3 were investigated by studying the electrical properties of the sensor elements fabricated from the synthesized powder. The maximum response (similar to 90%) of the sensor to 1000 ppm n-butane at 300 degrees C can be explained on the basis of catalytic activity of the nanocrystallites. The response and recovery time of the sensor to 1000 ppm n-butane were less than 12 s and 120 s, respectively. (c) 2008 Published by Elsevier B.V.