Published online by Cambridge University Press: 21 February 2011
New proton conducting materials were prepared and characterized for potential applications in humidity sensing at temperatures higher than 100°C by complex impedance or galvanic cell type techniques. Calcium metaphosphate, β-Ca(PO3)2 as a galvanic cell type sensor material yields reproducible signals in the range from 5 to 200 nmm Hg water vapor pressure at 578°C, with short response time(-30 sec). Polycrystalline samples of α-Zr(HPO4)2 and KMO3 P5.8Si2O25, and the gel converted ceramic, 0.10Li2O-0.25P2O5-0.65SiO2 as impedance sensor materials show decreases in impedance with increasing humidity in the range from 9 nmn Hg to 1 atm water vapor pressure at 179*C.