Evolution of Luminescence of Sr_{2&#x2013;<i>y</i>&#x2013;<i>z</i>}Ca_<i>z</i>Si(O_{1&#x2013;<i>x</i>}N_<i>x</i>)₄:<i>y</i>Eu²⁺ with N^3&#x2013;, Eu²⁺, and Ca²⁺ Sub

다국어 초록 (Multilingual Abstract)

<P>Sr<SUB>2–<I>y</I>–<I>z</I></SUB>Ca<SUB><I>z</I></SUB>Si(O<SUB>1–<I>x</I></SUB>N<SUB><I>x</I></SUB>)<SUB>4</SUB>:<I>y</I>Eu<SUP>2+</SUP> (SCSON:Eu<SUP>2+</SUP>) solid solutions were prepared by substituting N<SUP>3-</SUP>, Eu<SUP>2+</SUP>, and Ca<SUP>2+</SUP> ions into Sr<SUB>2</SUB>SiO<SUB>4</SUB> (SSO). These ions contributed differently to the evolution of luminescence of SCSON:Eu<SUP>2+</SUP>. SSON:Eu<SUP>2+</SUP> (<I>z</I> = 0) has two activation centers: Eu(I) and Eu(II). The nitridation effects led to a dramatic change in the crystal field surrounding the Eu(II) site but rarely affected the Eu(I) site. Accordingly, SSON:Eu<SUP>2+</SUP> exhibited broad excitation spectra from ultraviolet to visible wavelengths. In comparison with the Eu(II) green emissions of SSO:Eu<SUP>2+</SUP>, the dominant peak wavelengths (DPWs) of the Eu(II) emissions were at red emission regions (605–630 nm), depending on the amount of Eu<SUP>2+</SUP> ions. The Ca<SUP>2+</SUP> ions of SCSON:Eu<SUP>2+</SUP> preferentially changed the emission wavelength assigned to Eu(I) and affected the Eu(II) emission intensity. In addition to the spectral properties, the chromaticity coordinates and a low thermal quenching behavior of SCSON:Eu<SUP>2+</SUP> powders demonstrated that they can be a novel red phosphors for use in white light emitting diodes.</P><P>The dramatic red-shift from green to red and the enhanced emission intensity of Sr<SUB>2−<I>z</I></SUB>Ca<SUB><I>z</I></SUB>Si(O<SUB>1−<I>x</I></SUB>N<SUB><I>x</I></SUB>)<SUB>4</SUB>:Eu<SUP>2+</SUP>.</P><P><B>Graphic Abstract</B>
<IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/cgdefu/2013/cgdefu.2013.13.issue-12/cg400751n/production/images/medium/cg-2013-00751n_0011.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cg400751n'>ACS Electronic Supporting Info</A></P>