Exploring Optically Stable Reddish-Orange Fluorescent Magnetic Pigment (0.90)Y₂O₃:(0.10-x)Eu³⁺:(x)Bi³⁺ for...

Area of Science:

• Materials Science
• Nanotechnology
• Solid State Chemistry

Background:

• Yttrium oxide (Y2O3) is a promising host material for phosphors.
• Europium (Eu3+) and Bismuth (Bi3+) ions are known for their luminescent properties.
• Developing advanced materials for security applications is crucial.

Purpose of the Study:

• To synthesize and characterize Y2O3:Eu3+,Bi3+ nanophosphors.
• To investigate the effect of Bi3+ co-doping on the photoluminescence properties of Y2O3:Eu3+.
• To evaluate the potential of these nanophosphors as fluorescent magnetic pigments for security inks.

Main Methods:

• Chemical combustion citrate route for nanophosphor synthesis.
• Characterization using X-ray diffraction, Raman spectroscopy, FTIR, UV-Vis, and photoluminescence spectroscopy.
• Scanning electron microscopy for grain size analysis and magnetization measurements.

Main Results:

• Synthesized Y2O3:Eu3+,Bi3+ nanophosphors with grain sizes of 40-50 nm.
• Observed characteristic Eu3+ emission peaks, with the most intense at 611 nm (reddish-orange).
• Demonstrated efficient energy transfer from Bi3+ to Eu3+ ions.
• Identified optimal composition (x=0.04) with highest photoluminescence intensity and excellent optical stability.
• Confirmed soft magnetic behavior attributed to Eu3+ ions.

Conclusions:

• Y2O3:Eu3+,Bi3+ nanophosphors exhibit strong photoluminescence and magnetic properties.
• The optimal nanophosphor composition shows potential for anti-counterfeiting applications in security inks.
• These materials offer dual optical and magnetic security features.