TiO2:WO3 composite humidity sensors doped with ZnO and CuO investigated by impedance spectroscopy

Preparation, Characterization, and Evaluation of Humidity-Dependent Electrical Properties of Undoped and Niobium Oxide-Doped TiO2 : WO3 Mixed Powders

“…e mixtures (pristine and doped powders) were initially pelletized in the samples of 8 mm × 6 mm × 1 mm under 8 MPa of uniaxial pressure and then isostatically pressed at 200 MPa. Afterwards, the thermal treatment (under air) was conducted at 700°C for 2 h with heating and cooling rates of 20°C/min in accordance with a previous used procedure [8,9].…”

“…Equivalent circuits have been considered as an interesting source of parameters [25][26][27] that have been associated with di erent mechanisms in overall electrical response. e circuit represented in Figure 7 has been explored by the authors in recent works [8,9], and the components are described below: C geo is used to represent the geometrical capacitance, while the bulky granular response is assigned to R 1 //C 1 .…”

“…e typical process of structural modi cation is provided by mechanical mixing of the powders, molding, and sintering of the pelletized samples [8,9]. e introduction of a doping agent in a mixed metal oxide ceramic has been considered an interesting strategy for improvement in the dependence of impedance value with relative humidity (RH) variation [10][11][12][13].…”

One pot synthesis of mesoporous ZnO–SiO 2 nanocomposite as high performance humidity sensor

“…Being an important material in the family of n-type semiconductors, zinc oxide (ZnO) has attracted the interest of many researchers for its use in fabrication of RH sensors [26][27][28][29]. The water molecules get adsorbed on the surface of ZnO in molecular and hydroxyl form and causes electrical conduction at room temperature.…”

Optical Sensing Performance of Multimode Polymer Optical Fiber (POF) Coated with ZnO towards Methanol Vapour

“…Nowadays, many researchers implemented optical fiber detections scheme to sense the volatile organic compound using absorbance spectroscopy [15] and reflectance [16]. One of the most important thing to obtain a good sensitivity sensor performance is the use of material coating such as ZnO [17], PANI [18], Cerium oxide [19], and ITO [20].…”