Abstract
KLa2Ti3O9.5 and KLa2Ti3O9.5:Er3+ nanocrystals were successfully synthesized using a hydrothermal method and a subsequent calcination treatment. The band gap (Eg) of the KLa2Ti3O9.5 nanocrystals was calculated to be about 2.56 eV by means of the reflectance diffusion technique. Under 980-nm excitation, the KLa2Ti3O9.5:Er3+ nanocrystals emitted intense green (2H11/2/4S3/2 → 4I15/2) and red (4F9/2 → 4I15/2) upconversion (UC) luminescence. In comparison with pure KLa2Ti3O9.5, the KLa2Ti3O9.5:Er3+ nanocrystals exhibited a higher activity for water splitting into H2 under simulated solar light irradiation. We suggest that the enhancement of photocatalytic activity is related to the Brunauer-Emmett-Teller (BET) surface area and UC luminescence of KLa2Ti3O9.5:Er3+.
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ACKNOWLEDGMENTS
This work was supported by the National Natural Science Foundation of China (Grant Nos. 10979032, 21001042, and 21171052), the Program for New Century Excellent Talents in University of Ministry of Education of China (Grant No. NCET-11-0959), the Postdoctoral Science Foundation of Heilongjiang Province (Grant No. LBH-Q11009), and the Youth Foundation for Distinguished Young Scholars of Heilongjiang University.
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Li, Y., Qu, Y., Wang, G. et al. Synthesis, luminescence, and photocatalytic activity of KLa2Ti3O9.5:Er3+ nanocrystals for water decomposition to hydrogen. Journal of Materials Research 27, 2925–2929 (2012). https://doi.org/10.1557/jmr.2012.322
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DOI: https://doi.org/10.1557/jmr.2012.322