SYNTHESIS AND HUMIDITY SENSITIVE PROPERTIES OF NANOCRYSTALLINE BA1-XSRXTIO3 THICK-FILMS

Nanocrystalline Ba1-xSrxTiO3 (x=0, 0.2, 0.4, 0.6, 0.8 and 1.0) precurs ors were synthesized using the stearic acid gel method. After the prec ursors had been calcined at 600-950 degrees C for 0.5-1 h, nanocrystal line powders with the cubic perovskite structure were obtained and the se were made into thick films. The powder samples were characterized b y differential thermal analysis, X-ray diffraction and transmission el ectron microscopy, and the thick film samples were characterized by sc anning electron microscopy and X-ray diffraction. The humidity-sensiti ve properties of the nanocrystalline Ba1-xSrxTiO3 thick films were inv estigated. The results show that these nanocrystalline thick films pos sess higher humidity sensitivity and lower resistance than those of co nventional materials. (C) 1997 Elsevier Science S.A.