A co-precipitation technique to prepare CaNb2O6

A mixture of ammonium oxalate and ammonium hydroxide was used to co-precipitate calcium and niobium ions as calcium oxalate and niobium hydroxide under basic conditions. This precursor yielded CaNb2O6 (CN) ceramics on calcining at 750 °C, i.e. at a temperature much lower than 900 °C, reported for the formation of CaNb2O6 prepared by the traditional solid state method. Transmission electron microscope (TEM) investigations revealed an average particle size 100 nm for the calcined powders. The room temperature dielectric constant at 1 kHz was found to be 100. The ferroelectric hysteresis loop parameters of these samples were also studied.