Hydrothermal Synthesis of Fe2O3 for the Humidity Sensing Application

Abstract

Fe 2 O 3 nanorods have been successfully synthesized by a hydrothermal method using stainless steel Teflon autoclave. The solution of FeCl 3 and Urea was transferred to Teflon-lined stainless-steel autoclave and then maintained the temperature 180oC for 24 hrs. As prepared Fe 2 O 3 powder were characterized by X-ray Diffraction (XRD) and the result shows the formation of Hematite phase of Fe 2 O 3 after calcination at 400 o C of 2h. Field Emission Scanning Electron Microscopy (FESEM) was used to study the morphology of synthesized Fe 2 O 3 powder and the result indicates that bunch of nanorods were formed with width 44 nm and length of 220 nm. Also, Fourier Transform Infrared spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) techniques were used to characterize synthesized Fe 2 O 3 nanorods. To study the humidity sensing performance of Fe 2 O 3 nanorods, sensor was synthesized as interdigitated electrode coated with sensing material on top of the electrode. The present study investigated good humidity sensing performance of Fe 2 O 3 nanorods at room temperature in humidity (RH) range of 11%-97% at DC condition.