{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,19]],"date-time":"2026-06-19T05:29:07Z","timestamp":1781846947789,"version":"3.54.5"},"reference-count":25,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2017,8,26]],"date-time":"2017-08-26T00:00:00Z","timestamp":1503705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>In a series of (Ca2\u2013x\/2\u2013yEuy\u25a1x\/2)(Si1\u2013xPx)O4 (x = 0.06, 0.02 \u2264 y \u22640.5), various color-emitting phosphors were successfully synthesized by a solid-state reaction. These phosphors were characterized by photoluminescence (PL) spectroscopy, X-ray powder diffractometry, transmission electron microscopy, and X-ray absorption fine structure spectroscopy. We evaluated the effect of heat treatment on PL properties with various annealing temperatures at 1373\u20131773 K for 4 h before\/after reduction treatment from Eu3+ to Eu2+. In the red-emitting (Ca1.95Eu3+0.02\u25a10.03)(Si0.94P0.06)O4+\u03b4 phosphor, the highest PL intensity exhibited when it was annealed at 1773 K. On the other hand, in the green-emitting (Ca1.95Eu2+0.02\u25a10.03)(Si0.94P0.06)O4 phosphor, the highest PL intensity was realized when it was annealed at 1473 K and consequently treated under a reductive atmosphere. With increasing annealing temperature, the emission peak wavelength steadily decreased. Furthermore, with increasing Eu2+ content, the emission peak wavelength increased, with the color of emitting light becoming yellowish. Thus, the PL properties of the phosphors were affected by both the structural change from \u03b2 to \u03b1\u2019L, which occurred by heat treatment, and the amount of doped Eu ions.<\/jats:p>","DOI":"10.3390\/ma10091000","type":"journal-article","created":{"date-parts":[[2017,8,28]],"date-time":"2017-08-28T12:08:37Z","timestamp":1503922117000},"page":"1000","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["The Effect of Heat Treatment on the Emission Color of P-Doped Ca2SiO4 Phosphor"],"prefix":"10.3390","volume":"10","author":[{"given":"Hiromi","family":"Nakano","sequence":"first","affiliation":[{"name":"Cooperative Research Facility Center, Toyohashi University of Technology, Toyohashi 441-8580, Japan"},{"name":"Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Konatsu","family":"Kamimoto","sequence":"additional","affiliation":[{"name":"Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nobuyuki","family":"Yokoyama","sequence":"additional","affiliation":[{"name":"Department of Environmental and Life Sciences, Toyohashi University of Technology, Toyohashi 441-8580, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Koichiro","family":"Fukuda","sequence":"additional","affiliation":[{"name":"Department of Materials Science and Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,8,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2025","DOI":"10.1111\/j.1551-2916.2009.03169.x","article-title":"Characterization of Ca2SiO4: Eu2+ Phosphor Synthesized by Polymeric Precursor Process","volume":"92","author":"Choi","year":"2009","journal-title":"J. Am. Ceram. Soc."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2761","DOI":"10.1364\/OE.20.002761","article-title":"Yellow-emitting \u03b3-Ca2SiO4:Ce3+, Li+ phosphor for solid-state lighting: luminescent properties, electronic structure and white light-emitting diode application","volume":"20","author":"Jang","year":"2012","journal-title":"Opt. Express"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1016\/j.optmat.2014.07.017","article-title":"Monitoring of hydroxyapatite conversion by luminescence intensity of Eu3+ ions during mineralization of Eu3+-doped \u03b2-Ca2SiO4","volume":"37","author":"Zhang","year":"2014","journal-title":"Opt. Mater."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.spmi.2015.02.006","article-title":"Massive production of A2SiO4:Eu3+ and A2SiO4:Eu2+ (A = Ca, Sr, Ba) microspheres and luminescent properties","volume":"82","author":"Wei","year":"2015","journal-title":"Superlattices Microstruct."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"7756","DOI":"10.1002\/anie.201402520","article-title":"Tailoring of deep-red luminescence in Ca2SiO4: Eu2+","volume":"53","author":"Sato","year":"2014","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"117","DOI":"10.2109\/jcersj.105.117","article-title":"Structural change in phosphorus-bearing dicalcium silicates","volume":"105","author":"Fukuda","year":"1997","journal-title":"J. Ceram. Soc. Jpn."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/j.jallcom.2015.10.172","article-title":"Enhancement of photoluminescence intensity and structural change by doping of P5+ ion for Ca2\u2013x\/2(Si1\u2013xPx)O4: Eu2+ green phosphor","volume":"658","author":"Furuya","year":"2016","journal-title":"J. Alloys Compd."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Taylor, H.F.W. (1997). Cement Chemistry, Thomas Telford. [2nd ed.].","DOI":"10.1680\/cc.25929"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"460","DOI":"10.1557\/JMR.1999.0066","article-title":"Phenomenological analysis of \u03b1L\u2019-to-\u03b2 martensitic transformation in phosphorus-bearing dicalcium silicate","volume":"14","author":"Fukuda","year":"1999","journal-title":"J. Mater. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"2577","DOI":"10.1111\/j.1151-2916.1996.tb09018.x","article-title":"Structure change in strontium oxide-doped dicalcium silicates","volume":"79","author":"Fukuda","year":"1996","journal-title":"J. Am. Ceram. Soc."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2969","DOI":"10.1111\/j.1151-2916.1996.tb08735.x","article-title":"Thermal hysteresis for the \u03b1\u2032L \u21ab \u03b2 transformations in strontium oxide-doped dicalcium silicates","volume":"79","author":"Fukuda","year":"1996","journal-title":"J. Am. Ceram. Soc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1016\/j.materresbull.2016.07.002","article-title":"Enhancement of PL intensity and formation of core-shell structure in annealed Ca2\u2013x\/2(Si1\u2013xPx)O4:Eu2+ phosphor","volume":"83","author":"Nakano","year":"2016","journal-title":"Mater. Res. Bull."},{"key":"ref_13","first-page":"475","article-title":"Development of New Oxide Phosphors by Controlling Substitution Site of Lanthanide Ion","volume":"47","author":"Fujishiro","year":"2012","journal-title":"Nihon Daigaku Bunrigakubu Shizenkagakukenkyujo Kenkyukiyou"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2795","DOI":"10.1111\/j.1551-2916.2012.05372.x","article-title":"Synthesis and luminescent properties of a new Eu3+-doped Li1+x(Ta1\u2013zNbz)1\u2013xTixO3 Red phosphor","volume":"95","author":"Nakano","year":"2012","journal-title":"J. Am. Ceram. Soc."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"326","DOI":"10.1017\/S0885715615000688","article-title":"Crystal structures and enhancement of photoluminescence intensities by effective doping for lithium tantalate phosphors","volume":"30","author":"Ichioka","year":"2015","journal-title":"Powder Diffr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1016\/j.jssc.2011.11.046","article-title":"Synthesis of high efficient Ca2SiO4:Eu2+ green emitting phosphor by a liquid phase precursor method","volume":"189","author":"Luo","year":"2012","journal-title":"J. Solid State Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"3286","DOI":"10.1016\/j.jssc.2006.06.018","article-title":"Charge states of Ca atoms in \u03b2-dicalcium silicate","volume":"179","author":"Mori","year":"2006","journal-title":"J. Solid State Chem."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1696","DOI":"10.1107\/S0567740877006918","article-title":"Redetermination of \u03b2-dicalcium silicate","volume":"B33","author":"Jost","year":"1977","journal-title":"Acta Crystallogr."},{"key":"ref_19","first-page":"35","article-title":"Studies on the Dusting of Ca2SiO4\u2014The Crystal Structure of \u03b1\u2019L-Ca2SiO4","volume":"33","author":"Udagawa","year":"1979","journal-title":"Proc. Jpn. Cem. Eng. Assoc."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/BF01099075","article-title":"The Crystal Structure of Ca5(PO4)2SiO4 (Silieo-Carnotite)","volume":"16","author":"Dickens","year":"1971","journal-title":"Tschermaks Miner. Petrogr. Mitt."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"537","DOI":"10.1107\/S0909049505012719","article-title":"ATHENA, ARTEMIS, HEPHAESTUS: Data analysis for X-ray absorption spectroscopy using IFEFFIT","volume":"12","author":"Ravel","year":"2005","journal-title":"J. Synchrotron Radiat."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"072101-1-4","DOI":"10.7567\/APEX.6.072101","article-title":"Eu2+-Activated CaSrSiO4: a New Red-Emitting Oxide Phosphor for White-Light-Emitting Diodes","volume":"6","author":"Tezuka","year":"2013","journal-title":"Appl. Phys. Express."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"15","DOI":"10.4028\/www.scientific.net\/SSP.130.15","article-title":"Three-dimensional visualization in powder diffraction","volume":"130","author":"Izumi","year":"2007","journal-title":"Solid State Phenom."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1080\/14786444508520918","article-title":"The effect of grain or particle Size on X-ray reflections from mixed powders and alloys, considered in relation to the quantitative determination of crystalline substances by X-ray methods","volume":"36","author":"Brindley","year":"1945","journal-title":"Philos. Mag."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Young, R.A. (1993). Introduction to the Rietveld method. The Rietveld Method, Oxford University Press.","DOI":"10.1093\/oso\/9780198555773.001.0001"}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/10\/9\/1000\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:43:24Z","timestamp":1760208204000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/10\/9\/1000"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,8,26]]},"references-count":25,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2017,9]]}},"alternative-id":["ma10091000"],"URL":"https:\/\/doi.org\/10.3390\/ma10091000","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2017,8,26]]}}}