Niobate Explained

Niobate should not be confused with niobite.

A niobate is an oxo-acid salt formed by niobium(Nb), and the common forms are metaniobate (NbO₃⁻) and orthoniobate (NbO₄³⁻). The most common niobates are lithium niobate (LiNbO₃) and potassium niobate (KNbO₃).

Preparation

The niobate can be obtained by reacting niobium pentoxide with the corresponding oxide, hydroxide or carbonate.^[1] For example, reacting lithium carbonate with niobium pentoxide would obtain lithium niobate:^[2]

Li₂CO₃ + Nb₂O₅ → 2 LiNbO₃ + CO₂↑

Cobalt metaniobate can be obtained by heating a mixture of cobalt monoxide and niobium pentoxide:^[3]

CoO + Nb₂O₅ → Co(NbO₃)₂

Lanthanide oxides react with niobium pentoxide to form the lanthanide orthoniobates:^[4]

Ln₂O₃ + Nb₂O₅ → 2 LnNbO₄

Notes and References

1. 申泮文 等. 无机化学丛书 第八卷 钛分族 钒分族 铬分族. 科学出版社, 2011. pp 275-276
2. 朱文祥. 无机化合物制备手册. 化学工业出版社, 2006. pp 219. 【V-69】偏铌(V)酸盐
3. A Textbook of Inorganic Chemistry. Vol VI, Part III. Vanadium, Niobium and Tantalum. Charles Griffin & Company Ltd, 1929. pp 159. Cobalt Metaniobate
4. Li Jian, C. M. Wayman. Monoclinic-to-Tetragonal Phase Transformation in a Ceramic Rare-Earth Orthoniobate, LaNbO₄. J. Am. Ceram. Soc., 80 [3] 803–806 (1997). DOI: 10.1111/j.1151-2916.1997.tb02905.x