Combustion synthesis and optimization of Tb³⁺-doped AZr₂(PO₄)₃ (A⁺ = Li, Na, K) phosphors for mercury-free lamp and plasma display panels application

Abstract

Abstract

Tb-doped AZr₂(PO₄)₃ (AZP) green phosphors were synthesized by novel solution combustion method, and the excitation spectra of pure compound in the vacuum ultraviolet (VUV) regions are investigated. The VUV characteristic was optimized by Tb³⁺ concentration and by alkali metals (A = Li, Na, K) contents. The concentration quenching was observed when the concentration of Tb³⁺ was 2.0 at% of Zr₂. The band ranging from 130 to 160 nm in excitation spectra is due to the absorption band of host lattice or PO₄ groups; the band at 160–200 nm is related to the charge transfer (CT) transition of O–Zr. The strong band at 225 nm and the weak band at 261 nm in the excitation spectra are assumed to the spin-allowed and spin-forbidden f–d transitions (4f⁸ → 4f⁷5d¹) of Tb³⁺.The excitation and emission spectra indicate that the phosphors can be effectively excited by 147 and 172 nm, and demonstrated a satisfactory green light performance. The high luminescent intensity, excellent color purity and chemical stability of AZr₂(PO₄)₃:Tb³⁺ make it an attractive green-emitting phosphors for mercury-free luminescent lamp and plasma display panel. The prepared phosphor sample characterized using X-ray diffraction), scanning electron microscopy and VUV spectra was studied.

Keywords:

• solution combustion synthesis
• zirconium phosphates
• plasma display panels
• mercury-free fluorescent lamps

Acknowledgements

We are grateful to 4B8 VUV spectroscopy beamline scientists of Being Synchrotron Radiation Facility (BSRF), China, for providing access in recording VUV on beamline 4B8 under dedicated synchrotron mode by using remote access mode. The authors are also thankful to the Chairman FIST-DST Project, SGB, Amravati University, Amravati, for providing XRD facility for this work.

Disclosure statement

No potential conflict of interest was reported by the authors.