Photocatalytic effect of TiO2-coated CaLa2(MoO4)4 and CaLa2(MoO4)4:Er/Yb nano core-shells and upconversion photoluminescence properties of CaLa2(MoO4)4:Er/Yb phosphors

TiO2-coated CaLa2(MoO4)(4) and CaLa2(MoO4)(4):Er/Yb nano core-shells were successfully synthesized using two-step procedures of the microwave sol-gel and ultrasonic methods. Well-crystallized nano core-shells showed a fine and homogeneous morphology with particle sizes of 10-20 nm. The degradation efficiency for TiO2-coated CaLa2(MoO4)(4) and CaLa1.7(MoO4)(4):Er0.1Yb0.2 under visible light resulted in the order as 10 > 15 > 5 wt%. Under excitation at 980 nm, the upconversion intensities of CaLa1.7(MoO4)(4):Er0.1Yb0.2 and CaLa1.5(MoO4)(4):Er0.05Yb0.45 particles exhibited a strong 525 nm and a weak 550 nm emission bands in the green region. The CIE diagram showed a good match with yellowish green emissions. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.