New Synthesis of Novel Phosphor for LED Technology: Sr3Y2(BO3)4:Eu Using Sr3B2O6:Eu and SrB4O7:Eu Precursors
Document Type
Oral Presentation
Campus where you would like to present
SURC 137B
Start Date
16-5-2013
End Date
16-5-2013
Abstract
Phosphors, used in plasma screens, medical imaging, and LED lighting, are materials that absorb energy and emit light. A promising activator for use in phosphors is divalent europium (Eu2+). Depending on the host, this dopant can emit anywhere in the visible spectrum. However, in many host compounds, it is difficult to dope Eu2+ due to the stability of trivalent europium (Eu3+). The literature indicates that the phosphor SrB4O7 readily incorporates Eu2+ into its structure, but that Sr3B2O6 does not. Here, we show that we can increase the ratio of Eu2+ emission to Eu3+ emission in Sr3B2O6:Eu by using SrB4O7:Eu2+ as a precursor. Divalent europium emission in Sr3Y2(BO3)4 has not been reported in the literature. To look for Eu2+ emission, we prepared samples of Sr3Y2(BO3)4 by using Sr3B2O6 and SrB4O7 precursors. Samples of SrB4O7:Eu precursor were prepared using traditional methods: grinding stoichiometric amounts of strontium carbonate, boric acid, and europium oxide and firing in a reducing atmosphere. To make the Sr3B2O6:Eu precursor, portions of the SrB4O7:Eu precursor were ground with stoichiometric amounts of SrCO3, and samples were fired in a reducing atmosphere again. To transform the precursors, the SrB4O7 precursor was ground with stoichiometric amounts of yttrium oxide and strontium carbonate, and fired in a reduction furnace. Sr3B2O6 precursor was ground with stoichiometric amounts of yttrium oxide and boric acid, and fired in a reduction furnace. We show that undoped samples of Sr3B2O6 and SrB4O7 can be transformed phase-pure to Sr3Y2(BO3)4. This method may lead to previously unmade novel phosphors.
Recommended Citation
Kilburn, Troy and Way, Zachary, "New Synthesis of Novel Phosphor for LED Technology: Sr3Y2(BO3)4:Eu Using Sr3B2O6:Eu and SrB4O7:Eu Precursors" (2013). Symposium Of University Research and Creative Expression (SOURCE). 57.
https://digitalcommons.cwu.edu/source/2013/oralpresentations/57
Additional Mentoring Department
Chemistry
New Synthesis of Novel Phosphor for LED Technology: Sr3Y2(BO3)4:Eu Using Sr3B2O6:Eu and SrB4O7:Eu Precursors
SURC 137B
Phosphors, used in plasma screens, medical imaging, and LED lighting, are materials that absorb energy and emit light. A promising activator for use in phosphors is divalent europium (Eu2+). Depending on the host, this dopant can emit anywhere in the visible spectrum. However, in many host compounds, it is difficult to dope Eu2+ due to the stability of trivalent europium (Eu3+). The literature indicates that the phosphor SrB4O7 readily incorporates Eu2+ into its structure, but that Sr3B2O6 does not. Here, we show that we can increase the ratio of Eu2+ emission to Eu3+ emission in Sr3B2O6:Eu by using SrB4O7:Eu2+ as a precursor. Divalent europium emission in Sr3Y2(BO3)4 has not been reported in the literature. To look for Eu2+ emission, we prepared samples of Sr3Y2(BO3)4 by using Sr3B2O6 and SrB4O7 precursors. Samples of SrB4O7:Eu precursor were prepared using traditional methods: grinding stoichiometric amounts of strontium carbonate, boric acid, and europium oxide and firing in a reducing atmosphere. To make the Sr3B2O6:Eu precursor, portions of the SrB4O7:Eu precursor were ground with stoichiometric amounts of SrCO3, and samples were fired in a reducing atmosphere again. To transform the precursors, the SrB4O7 precursor was ground with stoichiometric amounts of yttrium oxide and strontium carbonate, and fired in a reduction furnace. Sr3B2O6 precursor was ground with stoichiometric amounts of yttrium oxide and boric acid, and fired in a reduction furnace. We show that undoped samples of Sr3B2O6 and SrB4O7 can be transformed phase-pure to Sr3Y2(BO3)4. This method may lead to previously unmade novel phosphors.
Faculty Mentor(s)
Anthony Diaz