New lanthanide-free self-activated full-color emission phosphor in Y 3+ doped Sr 3 Bi(VO 4 ) 3 system for white light emitting diode applications

• Published in: Luminescence (Chichester, England) England), 2021-05, Vol.36 (3), p.819-825
• Main Authors: Sreena, T S, Rao, P Prabhakar, Thara, T R Aju, Raj, Athira K V
• Format: Article
• Language: English
• ISSN: 1522-7235; 1522-7243
• DOI: 10.1002/bio.4007

Commercially used inorganic phosphors heavily depend on lanthanide doped host materials which are becoming more expensive and also their availability is limited due to scarcity. In this regard, a new lanthanide-free self-activated full-color emission phosphor in Y doped Sr Bi(VO ) system was developed by the conventional ceramic route. These phosphors crystallize into a hexagonal-type palmierite mineral structure. They exhibit broad excitation bands in the wavelength region of 250-400 nm, owing to the charge transfer transitions from both O and Bi6s electrons to V . Upon excitation, these phosphors show bright broad emissions in the 400-750 nm wavelength range, peaking around 535 nm, with a large full width half maximum of 160 nm. The Y substitution allows tuning of the emission from yellowish green to bluish white due to increased distortion of [VO ] tetrahedron. Consequently, the CIE color coordinates changed from (0.42, 0.50) to (0.31, 0.35) which lies in the near-white region in the chromaticity diagram. Thus, the newly developed Y doped Sr Bi(VO ) is a promising lanthanide-free full-color emission phosphor for applications in pc-white light emitting diodes.