Synthesis of Potassium Niobate from Metal Alkoxides

Preparation of potassium niobate from metal alkoxides was investigated. Potassium‐niobium ethoxide, KNb(OC 2 H 5 ) 6 , and potassium‐niobium propoxide, KNb(OC 3 H 7 ) 6 , were synthesized and subsequently hydrolyzed using several water concentrations (0.75 to 6.0 mol of water/(mol of alkoxide)). Rapid precipitation of potassium‐deficient particles occurred when higher concentrations of water were used. This resulted in the formation of a multiphase material after calcination, as X‐ray diffraction showed the presence of both KNbO 3 and potassium‐deficient oxide phases(s). Single‐phase KNbO 3 could be prepared by two methods: (1) hydrolysis of KNb(OC 3 H 7 ) 6 /propanol solutions using 1 mol of water (per mole of propoxide) added as a water/propanol solution and (2) hydrolysis of KNb(OC 2 H 5 ) 6 /ethanol solutions using 1 mol of water (per mole of ethoxide) added as a water/methanol solution. The latter method provided advantages of low calcination temperature for the formation of single‐phase KNbO 3 and low weight loss after calcination.