Synthesis and characterization of (Zn, Mn)TiO3 by modified sol-gel route

Hexagonal ilmenite-type (Zn1-xMnx)TiO3 (0 <= X <= 0.9) ceramic powders were synthesized by a sol-gel route including the Pechini process with heat treatments at 600 degrees C for 3 h and 800 degrees C for 6 h. The thermal stability of ZnTiO3 dielectric ceramics was improved (> 1200 degrees C) by doping manganese. The dielectric constant of (Zn1-x,Mn-x)TiO3 ceramic was higher than those of (Zn, M)TiO3 (M = Co, Ni, etc.), increased with the amount of manganese in the range of 0 <= x < 0.7 then decreased after the maximum point at x = 0.7 in the same frequency. Both the dielectric loss tangent and the dielectric constant decreased with increasing the measured frequencies. The value of dielectric loss tangent was relatively high because of magnetoresistive effect of manganese. (c) 2007 Elsevier B.V. All rights reserved.