Facile method to prepare copper-doped LiNbO3 nanocrystals

A facile method to prepare copper-doped LiNbO₃ nanocrystalline is reported. It should be mentioned here that the harmless citric acid plays a key role in soluble niobate at first and in the formation of the uniform gel. A detail thermal behaviour of the as-obtained gel was investigated by thermogravimetry and differential thermal analysis. The crystal structure, elemental composition and microstructural properties were characterised by X-ray diffraction analysis, X-ray photoelectron spectroscopy and scanning electron microscopy. Results indicate that a pure phase similar to LiNbO₃, which has the cell parameters of a = b = 5.150(5) Å and c = 13.896(9) Å, can be obtained at a low temperature (~550°C) and the mean particle size of the as-synthesised nanocrystalline is about 40 nm.