Solution combustion derived nanocrystalline Zn(2)SiO(4):Mn phosphors: a spectroscopic view

Area of Science:

• Materials Science
• Solid State Chemistry
• Nanotechnology

Background:

• Willemite (Zn2SiO4) is a promising host material for phosphors.
• Manganese (Mn2+) doping is known to induce luminescence in various host lattices.
• Controlling synthesis parameters is key to achieving desired material properties.

Purpose of the Study:

• To synthesize manganese-doped nanocrystalline willemite phosphors (Zn(2-x)Mn(x)SiO4).
• To characterize the structural, phase, and paramagnetic properties of the synthesized phosphors.
• To investigate the photoluminescence characteristics and the effect of manganese content on luminescence.

Main Methods:

• Solution combustion synthesis at low temperature.
• Characterization using X-ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Electron Paramagnetic Resonance (EPR), and Photoluminescence (PL) spectroscopy.
• Analysis of lattice parameters, phase transformation, EPR spectra, paramagnetic susceptibility, and luminescence emission.

Main Results:

• Successful synthesis of Zn(2-x)Mn(x)SiO4 phosphors with a rhombohedral space group (R3H).
• Phase transformation from beta-willemite to alpha-willemite observed at 950°C.
• EPR spectra confirmed two distinct Mn(2+) sites and an ionic environment, with parameters evaluated as a function of Mn content (x).
• Strong green emission peaking at 520 nm was observed under UV excitation (251 nm), attributed to the (4)T1 → (6)A1 transition of Mn(2+).

Conclusions:

• The synthesized manganese-doped willemite phosphors exhibit characteristic structural and paramagnetic properties.
• The green luminescence is effectively modulated by the manganese doping concentration.
• These findings highlight the potential of these phosphors for optoelectronic applications, particularly in lighting and display technologies.