Red-Emitting Phosphors for White LEDs: Optimizing Eu³⁺ Doping via Microwave-Assisted Synthesis

S B Pandey; A J Nadgawda; C S Khade

doi:10.63278/10.63278/mme.v31.1

Authors

S B Pandey Research Scholar, Department of Physics, G H Raisoni University, India
A J Nadgawda Research Scholar, Department of Physics, G H Raisoni University, India
C S Khade Assistant Professor, Department of Physics, G H Raisoni University, India

DOI:

https://doi.org/10.63278/10.63278/mme.v31.1

Keywords:

Luminescent, Phosphors, Solid State Metathesis Synthesis, wLED.

Abstract

Europium-doped calcium molybdate phosphors CaMoO4:xEu3+ were made using the microwave-assisted solid state metathesis mode to enhance their suitability for near-UV-based white LEDs. X-ray diffraction analysis confirmed the formation of well-crystalline phosphors with a scheelite-type structure, indicating uniform incorporation of Eu3+ ions into the crystal lattice. The phosphors exhibited strong photoluminescence with a prominent emission peak at 618 nm under 392 nm excitation, attributed to the 5D0 → 7F2 transitions of Eu3+ ions. Optimization experiments determined that an 0.08mol% doping concentration of Eu3+ ions maximized the luminescence intensity, showcasing efficient energy transfer mechanisms within the material. The phosphors demonstrated favorable color rendering capabilities, as evidenced by their chromaticity coordinates (x = 0.668, y = 0.323), which closely approached NTSC standards. Fluorescence lifetime analysis revealed a mono-exponential decay curve with a lifetime of 0.401 ms for the 5D0 excited state of Eu3+. Overall, microwave-assisted synthesis enabled the production of homogeneous phosphors with fine structural characteristics, offering significant advantages in terms of efficiency and performance for future applications in solid-state lighting devices. These phosphors hold promise for enhancing the red component in LED technology, contributing to advancements in energy-efficient and high-quality lighting solutions.

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