Preparation and photoluminescence properties of CaSc2O4:Eu3+ red phosphor for white LEDs

The development of red phosphors has a significant impact on high-quality white LEDs lighting. In this research, the luminous properties of CaSc2O4:Eu3+ red phosphor were investigated after it was successfully produced using a high-temperature solid-state process. Upon excitation with near-ultraviolet (n-UV) light of 395 nm, CaSc2O4:Eu3+ phosphor emits luminescent red light with the emission peaks at 598 nm, 624 nm, 657 nm, and 707 nm, which is attributed to the transition of Eu3+ at 5D0 → 7FJ (J = 1, 2, 3, 4). When the doping concentration of Eu3+ ion is 10 mol%, concentration quenching occurs, and the quenching mechanism is hypothesized to be the dipole–dipole (d–d) interaction. The thermal stability (T50% = 523 K), quantum efficiency (65%), activation energy (0.14 eV), and decay time (0.112 ms) of CaSc2O4:Eu3+ phosphors were measured and calculated. The red LED and white LED devices fabricated with Ca0.9Sc2O4:0.1Eu3+ phosphor exhibit good luminous performance. In particular, the white light LED device emits bright neutral white light with correlated color temperature of 5062.35 K, color rendering index of 80.46, and the CIE chromaticity coordinates of (0.3431, 0.3527). The findings suggest that CaSc2O4:Eu3+ phosphor could be used as a potential red light component in n-UV light excited white LEDs.