Nanoporous gamma-alumina based novel sensor to detect trace moisture in high temperature and high pressure environment

Development of trace moisture sensor which can perform in high temperature and high pressure environment is always a challenging task though it is needed for some specific applications. This article delineates the synthesis and characterization of nanoporous gamma-alumina thin film through sol-gel followed by dip coating technique and fabrication of trace moisture sensor capable to work in high temperature and high pressure environment. The structure and morphology of the films were properly characterized using XRD, FESEM and AFM. High sensitivity and good quasi-linearity were obtained at the low frequency region and best linearity, which may be suitable for device application, was exhibited at 1 kHz. The linearity of sensor response at different moisture level is comparable with commercially available sensors. In addition, sensors are ultrasensitive having response and recovery time around 1 s and 1.5 s, respectively. A-combination of micro and nano pores in the electrode and gamma-alumina (gamma-Al2O3) films, respectively, could play an important role for achieving high and ultrafast sensitivity. (C) 2015 Elsevier B.V. All rights reserved