Elucidating Structure Composition Property Relationships of the b SiAlON:Eu2+ Phosphor
In this work, we performed a systematic investigation of structure composition property relationships in Eu2+ activated b SiAlON, one of the most promising narrow band green phosphors for high power light emitting diodes and liquid crystal display backlighting with wide color gamut. Using first principles calculations, we identified and confirmed various chemical rules for Si Al, O N, and Eu activator ordering within the b SiAlON structure. Through the construction of energetically favorable models based on these chemical rules, we studied the effect of oxygen content and Eu2+ activator concentrations on the local EuN9 activator environment, and its impact on important photoluminescence properties such as emission peak position (using the band gap as a proxy) bandwidth, and thermal quenching resistance. Increasing oxygen content is shown to lead to an increase in Eu N bond lengths and distortion of the EuN9 coordination polyhedron, modifying the crystal field environment of the Eu2+ activator, and result.