Highly selective acetone sensor based on Co3O4-decorated porous TiO2 nanofibers

Abstract

We report synthesis and characterization of Co 3 O 4 -decorated porous TiO 2 nanofibers obtained through a facile electrospinning followed by a hydrothermal process. A morphological characterization confirmed that the diameter of the nanofiber was 250–300 nm. It was composed of subgrains, while its surface was decorated with Co 3 O 4 nanoparticles with a diameter of 30–50 nm. The nanofiber had a porous body structure, which was conducive to the adsorption of acetone gas. The synthesized Co 3 O 4 -decorated porous TiO 2 nanofibers were used as sensing materials to fabricate acetone gas sensors. Their response and recovery times were systematically analyzed with respect to the operation temperature and acetone gas concentration. The observed gas response, response time, and recovery time of the nanofiber-based gas sensor were 71.88, 122 s, and 351 s, respectively, for 100-ppm acetone gas at an optimized temperature of 250 °C. Therefore, the Co 3 O 4 -decorated porous TiO 2 nanofibers could be a promising candidate for the fabrication of high-selectivity acetone gas sensors. • Porous TiO 2 nanofibers are synthesized through a facile electrospinning process. • Co 3 O 4 nanoparticles are decorated on nanofibers through a solvothermal process. • Various physical and electrical sensing characteristics of the nanofibers are analyzed. • Acetone sensing performance are analyzed and discussed its sensing mechanisms.