Low-temperature synthesis of BaMgAl10O17:Eu2+ blue phosphors

•Pure BaMgAl10O17:Eu2+ (BAM) blue phosphor could be successfully prepared by using H3BO3 as the flux in the solid-state reaction.•Well crystallized sub-micron BAM particles could be obtained by sintering at a temperature as low as 1100 °C for 2 h.•The reactivity of an intermediate, BaAl2O4, is thought to be the key factor influencing the synthesis temperature for BAM.

Using H3BO3 as the flux, pure BaMgAl10O17:Eu2+ (BAM) blue phosphors were successfully prepared via a solid-state reaction. By this approach, well-crystallized submicron BAM particles were obtained at temperatures as low as 1100 °C with a sintering duration of 2 h. The sintering temperature required by this approach was at least 400 °C lower than that required by the conventional solid-state approach for preparing BAM; moreover, the sintering time required by the former approach was also considerably shorter than that required by the latter approach. These factors are expected to lower the cost for large-scale production of BAM phosphors. Crystal structures and luminescence properties of the synthesized samples were characterized by XRD and TG–DTA, and photoluminescence spectroscopy, respectively. The reactivity of an intermediate, BaAl2O4, is thought to be the key factor influencing the synthesis temperature for BAM.

Graphical abstractAt each temperature, the duration time was fixed to be 2 h. The X-ray diffraction studies clearly showed that the raw materials react very slowly at 600 °C since the main phase detected was BaCO3. The increase of temperature could accelerate the reaction and BaAl2O4 could be well detected when the temperature reached 800 °C. When the temperature was further increased to 900 °C, only BaAl2O4 could be detected. When the sintering temperature increased to 1000 °C, BaMgAl10O17 emerged as the main phase with the co-existence of BaAl2O4 as the minority. Finally when the sintering temperature reached 1100 °C, pure BAM phase can be obtained.Figure optionsDownload full-size imageDownload as PowerPoint slide