Effect of Li+ doping on ZrO2-TiO2 humidity sensor

Humidity sensors are widely used in domestic and industrial environments. The authors have investigated 0.5ZrO(2)-0.5TiO(2) ceramic for its humidity sensing electrical properties at room temperature. The bulk humidity sensors were prepared by the conventional ceramic method. Salt doping with Li+ ions is found to increase the sensitivity by an order of two, and also improves the linearity. X-ray and scanning electron microscopy (SEM) investigations have established that ZrTiO4 phase grows at a sintering temperature of 1200 degrees C. The abnormal behaviour in humidity sensing characteristics for samples sintered at 1150 degrees C may be due to micropores in between the grains. (C) 1999 Elsevier Science S.A. All rights reserved.