Simultaneous improving luminescence intensity and stability, reduce cation vacancies of rare-earth doped CaF 2 by charge self-compensation

Abstract Although upconversion rare-earth (RE) materials have excellent luminescence properties, the luminescence intensity and thermal stability of phosphors are not favorable due to RE doping induced vacancies. This work focused on enhancing luminescence intensity and stability of phosphor by charge compensation and three-dimensional (3D) printing. The luminescence results showed that Ca0.697Yb0.2Er0.0015Tm0.0005F2 with charge compensation exhibited luminescence intensity 3.2 times higher than that of Ca0.798Yb0.2Er0.0015Tm0.0005F2 non-charge compensation. The luminescence of resin-coated luminescent materials is still stable after 6 months. The constructed white light-emitting diodes (WLEDs) also exhibit consistent and outstanding color rendering characteristics, with a color rendering index (CRI) of up to 81 and a low color temperature (CCT).