A facile chemical route to prepare Nd[(Zn0.7Co0.3)0.5Ti0.5]O3 powders and microwave dielectric materials

High-purity Nd[(Zn 0.7 Co 0.3 ) 0.5 Ti 0.5 ]O 3 powders with perovskite structure, which were employed to prepare microwave dielectric ceramics, were produced by a facile chemical route from a solution containing neodymium oxide, zinc nitrate hexahydrate, cobalt nitrate hexahydrate, tetrabutyl titanate, citric acid, and ethylene glycol based on a citrate precursor process. Furthermore, the sintering behavior, microstructure, and microwave dielectric properties of Nd[(Zn 0.7 Co 0.3 ) 0.5 Ti 0.5 ]O 3 ceramics were evaluated. XRD and FT-IR results showed that the polymeric precursor could directly transform into Nd[(Zn 0.7 Co 0.3 ) 0.5 Ti 0.5 ]O 3 powders without forming any intermediate phase. TEM results revealed that the as-obtained powders after calcination treatment at 800 °C were approximately spherical in shape and slightly agglomerated with an average particle size of 15 nm. Typical microwave dielectric properties of ε r = 35.26, Q × f = 236,800 GHz ( f = 9.52 GHz), and τ f = –28.6 ppm/°C were achieved for the Nd[(Zn 0.7 Co 0.3 ) 0.5 Ti 0.5 ]O 3 ceramics with a relative density of 98.7% sintered at 1250 °C for 2 h. The nanostructured Nd[(Zn 0.7 Co 0.3 ) 0.5 Ti 0.5 ]O 3 powders synthesized by a facile chemical route based on the citrate precursor exhibit high sintering ability and slightly agglomerated, which are attributed to the reduction of sintering temperature and improvement of microwave dielectric properties of the bulk ceramics. Highlights Single phase Nd[(Zn 0.7 Co 0.3 ) 0.5 Ti 0.5 ]O 3 powders were produced by the citrate precursor process. Nanoparticles prepared by the citrate precursor method possess high sinterability. High-quality microwave ceramics can be prepared at low sintering temperature. Citrate precursor route is an energy-efficient and simple method to prepare oxide ceramics.