Abstract
α‐Alumina films formed by anodic spark deposition in the melt of NaHSO4‐KHSO4 mixture (200°C) exhibited a porous structure. It has been found that the porosity and amount of α‐phase varied with anodic current density. By electrical measurements, films were found to exhibit a continuous open‐pore structure, causing failure of humidity sensors. This problem can be overcome by reanodization of the anodicspark‐deposited alumina films in either borax aqueous solution or sulfuric acid solution for a short time to form an effective barrier layer at the pore base. The modified anodic‐spark‐deposited alumina films showed highly sensitive response to water vapor change in the range of −76° to +20°C dew point with much improved long‐term stability. The humidity characteristics of the α‐alumina films were qualitatively explained in terms of the BET theory and condensation theory.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.