Correlation of luminescence and Judd-Ofelt intensity parameters in red ZrO2: Eu3+, Al3+ phosphor: The influences of Al3+ ions

Abstract This paper reports findings of synthesis of dual Eu3+/Al3+ doped ZrO2 phosphors (Zr0.99-xO2:0.01Eu3+, xAl3+) to achieve strong red emission, mainly by variation of Al3+(0 ≤ x ≤ 7). Zr0.99-xO2:0.01Eu3+, xAl3+ phosphors were synthesized via a co-precipitation route followed by annealing to 1000 °C in air. We utilized X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), photoluminescence spectra (PL), and Judd-Ofelt (J-O) theory to characterize the obtained Zr0.99-xO2:0.01Eu3+, xAl3+ phosphors for optoelectronic applications. It was found that the Zr0.99-xO2:0.01Eu3+, xAl3+ phosphors were in a tetragonal ZrO2 phase with the size of micro/nanoparticles of approximately 500 nm. The 3.0 mol% Al3+-doped phosphors showed dominant red 5D0→7F2 transitions. With calculations of Judd-Ofelt intensity parameters Ωλ (λ = 2 and 4), it was clear that the red electric dipole transition was pronounced for Zr0.99-xO2:0.01Eu3+, xAl3+ phosphors. The study offers a synthesis method for tetragonal Zr0.99-xO2:0.01Eu3+, xAl3+ red phosphors with strong photoluminescence which was also used for temperature sensing. A maximum relative sensitivity was 2.84% K−1 at 305 K, it also makes these potential candidates for optical temperature sensors.