A galvanic cell-type humidity sensor has been constructed from sintered β-Ca(PO3)2 which is a proton conductive solid. The EMF response as a function of the logarithm of water vapor is linear, reversible, reproducible, and very fast over a wide range of vapor pressure measured at 578, 678 and 776°C, respectively. The variation of observed EMF versus logarithm of water vapor is in good agreement with the theoretical EMF expected from the Nernst equation. Experimental results of steam-oxygen and steam-hydrogen concentration cells respectively employing β-Ca(PO3)2 as an electrolyte confirm proton conductivity and suggest the potential application of this material for high temperature galvanic cell-type humidity sensing.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics