title: Photoluminescence of Sinthetic Scapolite Na₄Ca₄Al₆Si₉O₂₄ Phosphors Activated with Ce³⁺ and Tb³⁺ and Energy Transfer from Ce³⁺ to Tb³⁺.
abstract: Natural scapolite including the S₂⁻ impurity is a typical silicate luminescent mineral. According to the formation conditions and chemical composition of natural scapolite, we synthesized Na₄ Ca₄ Al₆ Si₉O₂₄ (scapolite) by the high temperature solid-phase reaction, and prepared the synthetic scapolite phosphors activated with Ce³⁺ and Tb³⁺. The photoluminescence (PL) properties of the obtained phosphors were studied. The results indicated that the PL intensity of green (545 nm) emission corresponding to the ⁵D₄-->⁷F₅ transition within Tb³⁺ in the Ce³⁺, Tb³⁺-codoped samples was much higher than that of the Tb³⁺-doped samples. The PL properties of the samples activated with various Ce³⁺ concentrations were measured, and their fluorescence lifetime and energy transfer mechanism were analyzed. We proved that there was energy transfer from Ce³⁺ to Tb³⁺, and the energy transfer efficiency was at its maximum when the Ce³⁺ to Tb³⁺ mass ratio was 0.02: 0.03. Upon measurement by chromaticity coordinates, we found that the luminescence of the samples could be adjusted in the green area with varying Ce³⁺ concentrations. We thus deem that scapolite phosphors Na₄Ca₄ Al₆ Si₉ O₂₄:Ce³⁺, Tb³⁺ are promising to become the new white LED phosphors.
authors.forename: Yuan-yuan
authors.initials: YY
authors.lastname: Ma
authors.forename: Jiu-yang
authors.initials: JY
authors.lastname: He
authors.forename: Aziguli
authors.initials: A
authors.lastname: Reheman
authors.forename: Bahadeer
authors.initials: B
authors.lastname: Rouzi
authors.forename: Aierken
authors.initials: A
authors.lastname: Sidike