Investigation of Ammonia-Sensing Characteristics of Electrospun Fe 2 O 3 Nanograins

Fe 2 O 3 nanofibers were prepared using iron (II) chloride anhydrous and polyvinyl alcohol (PVA) by a simple electrospinning technique on a glass substrate. The deposited Fe 2 O 3 -based nanofibers were vacuum-annealed at 50°C for 35 min and calcinated at 450°C for 12 h to obtain Fe 2 O 3 nanograins. which were characterized by XRD, SEM, XPS, and FTIR. The XRD result shows the polycrystalline nature of Fe 2 O 3 . Also, from TEM analysis, we can observe that the Fe 2 O 3 nanograins formed along the axis of nanofibers. This continuous arrangement of nanograins along the axis is a promising structure for gas-sensing applications. The calcined Fe 2 O 3 nanograins showed a better response towards ammonia at 300°C. They also showed a quick response (14 s) and recovery (23 s) towards 5 ppm of ammonia vapor. Graphical Abstract