Hollow microspheres formed by nanograins of Cr1.8Ti0.2O3+z synthesized by ultrasonic spray pyrolysis for acetone detection

Abstract

The (Cr,Ti)2O3+z system, with corundum structure, has been studied due its technological application as gas or volatile compound detector. In this work we studied Cr1.8Ti0.2O3+z (CTO) particles grown by ultrasonic spray pyrolysis technique. The sample consists on hollow microspheres with a mean diameter of 12.8 μm, and the walls of the spheres are constituted by nanograins. Magnetic susceptibility studies and electron spin resonance spectroscopy showed a para- to antiferromagnetic transition at (306 ± 1) K. The acetone detection experiments were performed on compressed CTO forming a porous pellet. The CTO fabricated by spray pyrolysis detected very well acetone vapours with a linear response with the acetone concentration. This demonstrates that CTO particles produced by ultrasonic spray pyrolysis technique present high potentiality as volatile organic compounds detector. This synthesis route is economical and allows producing a great quantity of material in a short time, making this method adequate for large scale production.