Eu3+-activated Ca3Mo0.2W0.8O6 red-emitting phosphors: A near-ultraviolet and blue light excitable platform for solid-state lighting and thermometer

Abstract

Eu3+-activated Ca3Mo0.2W0.8O6 phosphors, which presented bright red emissions mainly from the 5D0 → 7F2 transition of Eu3+ ions upon the near-ultraviolet and blue light excitation, were successfully prepared by a traditional high-temperature technology. The crystal structure, phase constitution, morphology, electronic structure, photoluminescent behaviors, decay time, internal quantum efficiency and thermal stability of the resultant phosphors were investigated in detail. Under the excitation of 365, 393 and 465 nm, the optimal doping concentration was 9 mol% and the electrical multipolar interaction contributed to the non-radiative energy transfer between Eu3+ ions in Ca3Mo0.2W0.8O6 host lattices. Additionally, through using the prepared compounds, commercial blue/green-emitting phosphors and light-emitting diodes (LEDs), the fabricated white-LEDs emitted warm white light with excellent performance, such as good CIE coordinates, high color rending index and low correlated color temperature, when driven by 30 mA of injection current. Ultimately, according to the response of the decay time to the temperature, the thermometric performances of the resultant phosphors in the temperature range of 298–573 K were studied. The maximum sensor sensitivity of the studied phosphors reached up to 1.16% K−1 at 523 K. These achievements revealed that Eu3+-activated Ca3Mo0.2W0.8O6 phosphors were promising candidates for solid-state lighting and thermometer.