Lanthanum cerate (La2Ce2O7): hydrothermal synthesis, characterization and optical properties
Tóm tắt
La2Ce2O7 nano-powders were synthesized via a hydrothermal reaction in a deionized water (S
1) and in a 2 M NaOH aqueous solution (S
2) at 180 °C for 48 h. La(NO3)3·H2O and (NH4)2Ce(NO3)6 were used in the stoichiometric 1:1 La:Ce molar ratio as raw materials. The obtained materials were crystallized in a cubic crystal structure with space group. The synthesized materials were characterized by powder X-ray diffraction technique and Fourier-transform infrared spectroscopy. To investigate the effect of the basic solution on the morphology of the obtained materials, the morphologies of the synthesized materials were studied by field emission scanning electron microscopy technique. The technique showed that the morphology of La2Ce2O7 samples changed from grain to rod-like structure in presence of the basic solution. Cell parameter refinements showed that these parameters were larger for S2 than those for S
1. Photoluminescence and ultraviolet visible spectra of the synthesized nanomaterials were also investigated.
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