Synthesis and highly efficient defect-related UV-blue band luminescence of KY3F10 nanocrystals

Defect-related luminescence, with advantages such as emission color tunability, low cost and low toxicity compared to ions activated luminescence, is a captivating route to develop luminescent materials. Herein, we synthesized KY3F10 phosphors by hydrothermal technique with citric acid as the chelator. SEM images indicate that the phosphors are of nanoscale and excess CA addition results in particle agglomeration. The undoped nanocrystals exhibit UV-blue band emission centered at 360 nm originated from the defects under 300 nm excitation. And the most efficient luminescence with internal quantum efficiency as high as 23.73 % has been obtained from the sample whose chelator consumption in the preparation procedure is half that of rare earth. This indicates that the lanthanide-free KY3F10 nanocrystals are highly efficient UV-blue-emitting phosphors. And just by doping with 3 mol% Sm3+, the emission color could be tuned to white as a combinative effect of blue band emission from defects and line emission from Sm3+.