Structural and electric properties of barium strontium titanate based ceramic composite as a humidity sensor

Ba0.6Sr0.4TiO3–MgTiO3 (BST–MT) composite ceramics were prepared by reaction of BST powders with molten MgCl2. The sintered composites exhibit a five orders of magnitude decrease in the dc resistivity as the relative humidity (RH) was increased from 5 to 92%. The ac conductivity of the samples obeys a power law at different temperatures within the frequency range of 10 Hz to 10 MHz.