A red-emitting Ca8MgLa(PO4)7:Ce3+,Mn2+ phosphor for UV-based white LEDs application.

Area of Science:

• Materials Science
• Solid-State Chemistry
• Luminescence

Background:

• Development of efficient red-emitting phosphors is crucial for advanced lighting technologies.
• Cerium (Ce3+) and Manganese (Mn2+) ions are known activators in various phosphor systems.
• Calcium magnesium lanthanum phosphate (Ca(8)MgLa(PO(4))(7)) is explored as a host material.

Purpose of the Study:

• To synthesize and characterize Ca(8)MgLa(PO(4))(7):Ce(3+),Mn(2+) phosphors.
• To investigate the effect of Ce(3+) co-doping on the photoluminescent properties, particularly Mn(2+) emission.
• To evaluate the potential of these phosphors for UV-based white light-emitting diodes (WLEDs).

Main Methods:

• Conventional solid-state reaction under a weak reductive atmosphere.
• X-ray diffraction (XRD) for crystal structure analysis.
• Photoluminescence spectroscopy to study emission and excitation properties.

Main Results:

• Successful synthesis of Ca(8)MgLa(PO(4))(7):Ce(3+),Mn(2+) phosphors.
• Red emission at 640nm, attributed to the Mn(2+) (4)T(1)((4)G)→(6)A(1)((6)S) transition, was significantly enhanced (6.4 times) with optimal Ce(3+) co-doping.
• Evidence of resonance-type energy transfer from Ce(3+) to Mn(2+) via a dipole-dipole mechanism was observed.
• Calculated energy transfer efficiency based on relative emission intensity.

Conclusions:

• Ca(8)MgLa(PO(4))(7):Ce(3+),Mn(2+) phosphors exhibit efficient red emission.
• Ce(3+) co-doping plays a vital role in enhancing Mn(2+) luminescence through energy transfer.
• These phosphors are promising candidates for red-emitting components in UV-based WLEDs due to their broadband UV absorption and suitable color coordinates.