MgO-Doped (Zr,Sr)TiO3 Perovskite Humidity Sensors: Microstructural Effects on Water Permeation

Abstract

Porous (Zr0.5,Sr0.5)TiO3 and MgO (1, 3, 5 mol%) doped ZST nanocomposites have been developed and investigated as humidity sensing elements. The surface area analyser and FESEM data have indicated that the MgO doped perovskites are contained of the macropores and grain size of about 77 to 87 nm. EFTEM proved the reduction of particle size by addition of MgO dopant concentration. While pure ZST shows BET surface area of about 58 m2/g, MgO doped samples exhibit about 12 m2/g. Sensor contained of ZST doped with 3 mol% MgO shows highest sensitivity with about four orders of magnitude change in impedance within the range of 20% to 95% RH.

Keywords

• humidity sensors
• perovskite materials
• thick film
• nanocomposites
• ceramic
• zirconium