Synthesis, characterization, and microwave dielectric properties of ZnTiTa2O8 ceramics with ixiolite structure obtained through the aqueous sol-gel process

摘要

Nano-sized ZnTiTa2O8 powders with ixiolite structure, with particle sizes ranging from 10 am to 30 nm, were synthesized by thermal decomposition at 950 degrees C. The precursors were obtained by aqueous sol-gel and the compacted and sintered ceramics with nearly full density were obtained through subsequent heat treatment. The microstructure and electrical performance were characterized by field emission scanning electron microscopy, x-ray diffraction, and microwave dielectric measurements. All the samples prepared in the range 950-1150 degrees C exhibit single ixiolite phase and relative density between similar to 87% and similar to 94%. The variation of permittivity and Q.f value agreed with that of the relative density. Pure ZnTiTa2O8 ceramic sintered at 1050 degrees C for 4 h exhibited good microwave dielectric properties with a permittivity of 35.7, Q.f value of 57,550 GHz, and the temperature coefficient of resonant frequency of about -24.7 ppm/degrees C. The relatively low sintering temperature and excellent dielectric properties in the microwave range would make these ceramics promising for applications in electronics. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.