Ionic doping and inversion of the characteristic of thin film porous Al2O3 humidity sensor

Characterization of Al2O3 thin films prepared by spray pyrolysis method for humidity sensor

“…They obtained a dielectric constant of 7.9 and breakdown electric field of 5 MV/cm. Nahar et al [13] studied the humidity related properties of capacitive sensors employing Al-porous Al 2 O 3 -Au structures prepared by anodization method. They observed that variation of capacitance is less at low RH and steeply rising at high RH for low current density films.…”

AC impedance spectroscopy: a new equivalent circuit for titania thick film humidity sensors

“…The variations observed in humidity measurements in ceramic sensors are originated by the chemical and physical adsorptions of water molecules existing in the atmosphere [8][9][10][11]. Some authors [12][13][14] reported that low and high humidity sensitivities are governed by different transport mechanisms, in which electronic conduction is included. It must be said that in our samples we did not find any trace of electronic conduction, and, more, in our interpretation of the results it seems that the same mechanisms exist at both low and high humidities.…”

Study of the preparation of γ-Al2O3 nano-structured hierarchical hollow microspheres with a simple hydrothermal synthesis using methylene blue as structure directing agent and their adsorption enhancement for the dye

“…Nanometer aluminium oxides have been widely used in various fields such as adsorbents, catalysts, composite materials [14][15][16], humidity sensors and optical materials [17,18] because they possess many properties such as high surface area [19], large pore volume [20] and high porosity [21]. Particularly, hydrothermal http://dx.doi.org/10.1016/j.cej.2015.02.020 1385-8947/Ó 2015 Elsevier B.V. All rights reserved.…”