Studying the effect of doping metal ions onto a crystalline hematite-based humidity sensor for environmental control

Humidity sensors have several applications in both industrial processing and environmental control. Pure and doped hematite has proved to exhibit remarkable humidity sensing properties. The aim of this investigation is to study the effect of doping of some metal ions (Li+, Mg+2, Ba+2, Sr+2, and Na+) onto the crystalline hematite and to determine their sensitivity towards relative humidity (RH). The obtained crystalline samples were characterized by X-Ray Diffraction (XRD) combined with Field Emission Scanning Electron Microscopy (FESEM). The doped sodium metal ions (Na+) hematite sample showed a significant response towards relative humidity at room temperature.