Synthesis, Structure, and Photoluminescence Properties of Ce³⁺-Doped Ca₂YZr₂Al₃O₁₂: A Novel Garnet Phosphor for White LEDs

Abstract

A novel garnet phosphor Ca 2 YZr 2 Al 3 O 12 :Ce 3+ (CY-ZA:Ce 3+ ) has been successfully designed and synthesized via the solid state method. The crystal structure, morphology, as well as their photoluminescence properties were investigated in detail. Under nearultraviolet (n-UV) excitation, CYZA:Ce 3+ exhibits cyan to green emission with the maxima from 484 to 503 nm when varying the Ce 3+ concentration. The internal quantum efficiency of the optimal sample is 56%. The concentration quenching of Ce 3+ emission occurs via the energy transfer among the nearest-neighbor ions. The thermal stability is superior compared with the Ba 2 SiO 4 :Eu 2+ commercial phosphor. These results suggest that CYZA:Ce 3+ can be considered as a potential candidate for white LEDs.

Insight into a novel rare‐earth‐free red‐emitting phosphor Li3Mg2NbO6:Mn4+: Structure and luminescence properties

“…There are four types of distinctive cation sites in the LMN unit cell. 39,40 As a result, the incorporation of Mn 4+ into the LMN host may induce defects such as V .. These isolated octahedrons share edges with adjacent ones, constructing the three-dimensional rock salt structure, which provides multiple suitable sites for Mn 4+ doping.…”

“…So, it can be concluded that the doping Mn 4+ ions may occupy the Nb 5+ sites in the LMN host. 39,40 As a result, the incorporation of Mn 4+ into the LMN host may induce defects such as V ..…”

NaBaY(BO3)2:Ce3+,Tb3+: A novel sharp green‐emitting phosphor used for WLED and FEDs

“…However, the preparation of these phosphors is very energy‐intensive, requiring high temperature and high pressure, which leads to the limitation for application in LEDs. For many oxides based green phosphors, such as M 2 SiO 4 (M = Sr, Ca, Ba), they always have disadvantage in thermal stability . Hence, it is imperative to develop a new type of oxide based green phosphors at low temperature to cut cost and have good thermal stability.…”

The Energy Transfer and Thermal Stability of a Blue‐Green Color Tunable K2CaP2O7:Ce3+,Tb3+ Phosphor

“…As a matter of fact, the I + 2 II 2+ P 2 O 7 (I = Li, Na, K, Rb, Cs, II = Mg, Ca, Sr, Ba) (e.g., Li 2 BaP 2 O 7 , K 2 MgP 2 O 7 , Cs 2 M 2+ P 2 O 7 (M 2+ = Ca, Sr), etc.) compound can be synthesized at a lower temperature of no more than 1073 K than aluminates, silicates, and other salts (above 1473 K) . Among this class of host materials, K 2 CaP 2 O 7 (KCPO) has adequately substitutable space (Ca 2+ radii is about 1.00 Å and K + radii is nearly 1.46 or 1.51 Å with seven or eight surrounding O atom) for RE ions.…”

“…compound can be synthesized at a lower temperature of no more than 1073 K than aluminates, silicates, and other salts (above 1473 K). 11,[15][16][17][18] Among this class of host materials, K 2 CaP 2 O 7 (KCPO) has adequately substitutable space (Ca 2+ radii is about 1.00 A and K + radii is nearly 1.46 or 1.51 A with seven or eight surrounding O atom) for RE ions. In view of above advantages, KCPO is believed to be an appropriate host substance for luminescent materials.…”