{"title":"CdS:Mn Nanocrystals in Transparent Xerogel Matrices: Synthesis and Luminescence Properties","authors":"G. Counio, S. Esnouf, T. Gacoin, J.-P. Boilot","doi":"10.1021/jp961937i","DOIUrl":null,"url":null,"abstract":"<p >Mn<sup>2+</sup>-doped CdS nanocrystals (1?2 nm in size) dispersed in organic?inorganic silica xerogels are prepared by combining a controlled precipitation of nanocrystals in inverted micelles, a separation as a pure capped cluster powder, and a dispersion in hydrolyzed silicon alkoxide. ESR study identified two Mn<sup>2+</sup> sites, one bulklike, and another one which is attributed to ions located near the surface and which represents the main contribution. The average number of Mn<sup>2+</sup> per particle is in the 0.2?0.8 range. The luminescence is characteristic of a Mn<sup>2+</sup> internal transition, with energy and lifetime as in bulk materials. This bright emission (quantum yield of 7%) corresponds to an energy transfer from surface trapped carriers to Mn<sup>2+</sup> ions. </p>","PeriodicalId":58,"journal":{"name":"The Journal of Physical Chemistry ","volume":null,"pages":null},"PeriodicalIF":2.7810,"publicationDate":"1996-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1021/jp961937i","citationCount":"103","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"The Journal of Physical Chemistry ","FirstCategoryId":"1","ListUrlMain":"https://pubs.acs.org/doi/10.1021/jp961937i","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 103
Abstract
Mn2+-doped CdS nanocrystals (1?2 nm in size) dispersed in organic?inorganic silica xerogels are prepared by combining a controlled precipitation of nanocrystals in inverted micelles, a separation as a pure capped cluster powder, and a dispersion in hydrolyzed silicon alkoxide. ESR study identified two Mn2+ sites, one bulklike, and another one which is attributed to ions located near the surface and which represents the main contribution. The average number of Mn2+ per particle is in the 0.2?0.8 range. The luminescence is characteristic of a Mn2+ internal transition, with energy and lifetime as in bulk materials. This bright emission (quantum yield of 7%) corresponds to an energy transfer from surface trapped carriers to Mn2+ ions.