Porous Ceramic Humidity Sensors Using Sol-Gel Processed ZrTiO4 Nanoparticles
Ceramic ZrTiO4 powders were prepared by a sol-gel method using zirconium oxychloride and titanium tetraisopropoxide. In situ high temperature X-ray diffraction results show that crystallization of the amorphous gel starts at 400°C. Single-phase ZrTiO4 nanoparticles of 46 nm average particle size, determined by nitrogen adsorption analysis, were obtained after heat treatment at 450°C for 1 h. After pressing these sinteractive powders, pellets with controlled pore size distribution were obtained by sintering at temperatures as low as 400°C. The analysis of pores by mercury porosimetry gives an average porosity of 45%. The electrical resistivity, determined by impedance spectroscopy measurements at 24°C under different humidity environments, shows the ability of these pellets to adsorb water vapor in the porous surfaces.
I.C. Cosentino et al., "Porous Ceramic Humidity Sensors Using Sol-Gel Processed ZrTiO4 Nanoparticles", Advances in Science and Technology, Vol. 45, pp. 1803-1808, 2006