NO2 Sensing Properties of Porous In2O3-Based Powders Prepared by Utilizing Ultrasonic-Spray Pyrolysis Employing PMMA Microsphere Templates: Effects of the Size of the PMMA Microspheres on Their Gas-Sensing Properties

PMMA microspheres were synthesized in distilled water by ultrasonic-assisted emulsion polymerization. The average particle size of PMMA microspheres was dependent markedly on the kind of surfactant used. Porous (pr-) In2O3 powders were prepared by ultrasonic-spray pyrolysis of In(NO3)3 aqueous solution containing the PMMA microspheres synthesized. The NO2 response of pr-In2O 3 was much larger than that of conventional In2O 3 powder prepared by the similar technique employing PMMA-free In(NO3)3 aqueous solution. The introduction of controlled macroporous structure into the powder of the sensor material was found to be effective for improving NO2 response properties.Symposia on Chemical Sensors 10 - Chemical and Biological Sensors and Analytical Systems and Microfabricated and Nanofabricated Systems for MEMS/NEMS 10 - 222nd ECS Meeting/PRiME 2012; Honolulu, HI; United States; 7 October 2012 through 12 October 201