White-light-emitting properties of SrTiO₃:Pr³⁺ nanoparticles

Single-phase SrTiO₃:mPr³⁺ (m = 0.01-0.1) nanoparticles have been synthesized by a hydrothermal method. Different from reported Pr³⁺-based phosphors which were all dominated by red emissions, considerably strong and overwhelming blue-green emission centered at 491 nm has been achieved together with minor green and red emissions. The absolute and relative intensities of these emissions can be modified by Pr³⁺ concentrations and annealing temperatures in a controlled manner, giving rise to varied emission colors. In particular, owing to the appropriate combination of the blue to red emissions, desirable white-light emission has been realized from the as-grown SrTiO₃:0.01Pr³⁺ and the annealed SrTiO₃:0.06Pr³⁺ samples at 350 °C with CIE chromaticity coordinates of (0.33, 0.35) and (0.35, 0.37) and a correlated color temperature of 5601 K and 4883 K, respectively, indicating the promising application potential of SrTiO₃:Pr³⁺ as single-phase phosphors for white light-emitting-diodes. This work may provide a fresh route to acquire white emission from a single-composition phosphor.