Niobate

Not to 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

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