Synthesis and characterization of Zn–B–Si–O nano-composites and their doped BaTiO3 ceramics

We synthesized Zn–B–Si–O (ZBSO) nano-composites via sol–gel process, and then used them to dope BaTiO3 ceramics. The ZBSO nano-composites and their ceramics were characterized by means of thermogravimetric, Fourier-transform infrared, and X-ray diffraction methods, and using scanning and transmission electron microscopy. We also characterized the dielectric properties of the ceramics. The results indicated that the ZBSO nano-composites were nanometer-scale powders with an amorphous structure. The particle size of the powders increased with increasing pH value, but initially decreased and then increased with increasing calcining temperature. At pH about 2 and with calcining at 400 °C, the nano-composites attained minimum particle size (about 30 nm). The sintering temperature of the BaTiO3 ceramics could be reduced to 1100 °C by adding 5 wt% of the ZBSO nano-composites. Uniform, fine-grained BaTiO3 ceramics with a high permittivity (ɛr = 2946 and ɛmax = 5072) were obtained by adding nano-composites; these properties were superior to the ZBSO glass doped BaTiO3 ceramics.