{"id":970,"date":"2021-09-16T20:58:21","date_gmt":"2021-09-16T12:58:21","guid":{"rendered":"http:\/\/polyhedra.cn\/zh\/?p=970"},"modified":"2022-09-07T09:57:54","modified_gmt":"2022-09-07T01:57:54","slug":"yellow-persistent-luminescence-and-electronic-structure-of-ca-%ce%b1-sialon-eu2","status":"publish","type":"post","link":"http:\/\/ustb.cc\/zh\/yellow-persistent-luminescence-and-electronic-structure-of-ca-%ce%b1-sialon-eu2\/","title":{"rendered":"Yellow persistent luminescence and electronic structure of Ca-\u03b1-Sialon: Eu2+"},"content":{"rendered":"\n<p><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-vivid-cyan-blue-color\"><strong>J. Alloys Compd., <\/strong><\/mark><strong>2020, 821, 153482<\/strong>. <a rel=\"noreferrer noopener\" href=\"https:\/\/doi.org\/10.1016\/j.jallcom.2019.153482\" data-type=\"URL\" data-id=\"https:\/\/doi.org\/10.1016\/j.jallcom.2019.153482\" target=\"_blank\">https:\/\/doi.org\/10.1016\/j.jallcom.2019.153482<\/a><\/p>\n\n\n\n<p class=\"has-text-align-left\">Ca-\u03b1-Sialon: Eu<sup>2+<\/sup>, a well-known yellow phosphor, has been widely studied due to its broad UV-blue excitation with high quantum efficiency. Herein, we report the yellow persistent luminescence (PersL) of a series of Ca-\u03b1-Sialon: Eu<sup>2+<\/sup>&nbsp;compounds with chemical formula CaSi<sub>10-n<\/sub>Al<sub>2+n<\/sub>O<sub>n<\/sub>N<sub>16-n<\/sub>:&nbsp;<em>x<\/em>Eu<sup>2+<\/sup>&nbsp;(m&nbsp;=&nbsp;2, n&nbsp;=&nbsp;0\u223c1,&nbsp;<em>x<\/em>&nbsp;=&nbsp;0.1%\u223c8%) prepared by high-temperature solid-state method. Upon 254&nbsp;nm ultraviolet excitation, Ca-\u03b1-Sialon: Eu<sup>2+<\/sup>&nbsp;shows yellow PersL, and the persistent time is strongly dependent on the Eu<sup>2+<\/sup>&nbsp;and oxygen concentrations. The best persistent time is measured to be about 60&nbsp;min for the CaSi<sub>10<\/sub>Al<sub>2<\/sub>N<sub>16<\/sub>: 0.5% Eu<sup>2+<\/sup>&nbsp;sample. A very broad trap depth distribution, i.e. 0.6\u20131.4&nbsp;eV, originating from two categories, are obtained by analyzing preheating&nbsp;<a href=\"https:\/\/www.sciencedirect.com\/topics\/materials-science\/thermoluminescence\">thermoluminescence<\/a>&nbsp;(TL) spectra using initial rise method. Comparing thermoluminescence excitation spectra (TLEs) with&nbsp;<a href=\"https:\/\/www.sciencedirect.com\/topics\/materials-science\/photoluminescence\">photoluminescence<\/a>&nbsp;excitation spectra (PLEs), we verify that electrons as charge carriers are excited from 4<em>f<\/em>&nbsp;ground state of Eu<sup>2+<\/sup>&nbsp;to conduction band (CB) directly in the charging process for PersL. By functional theory (DFT) calculations, we verify that the trap levels responsible for PersL are impurity defects including V<sub>O<\/sub>&nbsp;and V<sub>N<\/sub>&nbsp;in Ca-\u03b1-Sialon. Furthermore, the PersL mechanism is given on the basis of constructing the host referred binding energy (HRBE) diagram. By virtue of NIR photo-stimulating PersL spectrum, we demonstrate that Ca-\u03b1-Sialon has a potential application in anti-counterfeit and information storage. This work would encourage more exploration of Eu<sup>2+<\/sup>-doped&nbsp;<a href=\"https:\/\/www.sciencedirect.com\/topics\/materials-science\/nitride-compound\">nitride<\/a>&nbsp;phosphor for persistent or long-persistent luminescence.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>J. Alloys Compd., 2020, 821, 153482. https:\/\/doi.org\/10 [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27],"tags":[98,96,97],"class_list":["post-970","post","type-post","status-publish","format-standard","hentry","category-lab_papers_2020","tag-sialon","tag-96","tag-97"],"_links":{"self":[{"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/posts\/970","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/comments?post=970"}],"version-history":[{"count":5,"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/posts\/970\/revisions"}],"predecessor-version":[{"id":1899,"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/posts\/970\/revisions\/1899"}],"wp:attachment":[{"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/media?parent=970"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/categories?post=970"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/ustb.cc\/zh\/wp-json\/wp\/v2\/tags?post=970"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}