Abstract
In order to develop high efficiency red emitting phosphors, Ca0.76MoO4: Eu 3+0.24 samples are investigated via sol–gel and solid state reaction. The XRD analysis reveals that both methods can synthesize phosphors with tetragonal CaMoO4 phase successfully. Smaller crystal size of samples prepared by sol–gel can be observed, and the grain size of these samples are around 100–200 nm, which is also smaller than the one prepared by solid state reaction. All phosphors present a red emission at 616 nm wavelength and one sol–gel synthesized sample exhibits the strongest emission intensity because of the higher quantum efficiency. It is attributed to the removal of lattice defects by sol–gel, in which way luminescent efficiency is enhanced. This can be reflected by the longer fluorescent lifetime of phosphors.
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The authors acknowledge the financial support from the National Natural Science Foundation of China (Nos. 21071034). The authors are also grateful to Instrumental Analysis and Research Center, Sun Yat-sen University for their performance of SEMs.
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Wu, H., Hu, Y., Zhang, W. et al. Sol–gel synthesis of Eu3+ incorporated CaMoO4: the enhanced luminescence performance. J Sol-Gel Sci Technol 62, 227–233 (2012). https://doi.org/10.1007/s10971-012-2716-8
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DOI: https://doi.org/10.1007/s10971-012-2716-8