Optical Materials: X最新文献_第10页

Enhanced thermoluminescence, radioluminescence, and optically stimulated luminescence from lithium fluoride and silver nanoparticles composites 增强氟化锂和银纳米颗粒复合材料的热致发光、放射发光和光激发发光

Optical Materials: X Pub Date : 2023-12-18 DOI: 10.1016/j.omx.2023.100287

Fraylenin Pinto Capia, Eder Jose Guidelli

{"title":"Enhanced thermoluminescence, radioluminescence, and optically stimulated luminescence from lithium fluoride and silver nanoparticles composites","authors":"Fraylenin Pinto Capia, Eder Jose Guidelli","doi":"10.1016/j.omx.2023.100287","DOIUrl":"10.1016/j.omx.2023.100287","url":null,"abstract":"<div>Plasmonic properties of metals can increase the sensitivity of ionizing radiation dosimeters. In this work, we study the plasmon resonance of silver nanoparticles (AgNp) to increase the optically stimulated luminescence (OSL) intensity of lithium fluoride (LiF) polycrystals. We produced LiF/Ag nanocomposites with different volumes of a silver nanoparticle dispersion and investigated their OSL response. We also investigated their thermoluminescence (TL) and radioluminescence/scintillation (RL) responses. X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV–vis spectroscopy characterized the synthesized materials. XRD results clearly show the characteristic peaks of LiF and AgNps. TEM images revealed silver nanoparticles with diameters between 80 and 120 nm and LiF crystals with sizes between 1 and 5 μm. Reflectance spectroscopy showed a band around 420 nm, attributed to the plasmon resonance of silver nanoparticles. The responses of the OSL curves to X-ray irradiation were analyzed, showing higher OSL sensitivity with 14 mL AgNp, attributed to the AgNp plasmon resonance. A significant increase in TL and RL intensity could be observed for the LiF/Ag nanocomposites. TL, RL, and OSL results support that addition of AgNps do not lead to the creation of more and new traps or luminescent centers. The increase of TL and RL intensities is therefore related to the coupling of the luminescent centers with the AgNPs plasmons, in an energy-transfer mechanism (plasmon-coupled emission), whereas the enhanced OSL intensity directly correlates with the increased photoionization cross-section of the electronic traps under plasmon resonance conditions (plasmon-coupled excitation). Therefore, these results indicate that AgNp are potential candidates to increase the OSL, TL, and RL intensity from LiF dosimeters.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"21 ","pages":"Article 100287"},"PeriodicalIF":0.0,"publicationDate":"2023-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S259014782300061X/pdfft?md5=ea1363c64e20787e74b257ea9a684e2d&pid=1-s2.0-S259014782300061X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138985880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

AgNPs incorporated in Eu(III)-doped hydroxyapatite biomaterial: Spectroscopic, cytotoxicity, and antimicrobial investigation 掺杂 Eu(III) 的羟基磷灰石生物材料中的 AgNPs：光谱、细胞毒性和抗菌研究

Optical Materials: X Pub Date : 2023-12-17 DOI: 10.1016/j.omx.2023.100286

Lauany Mazzon Pontes, João Vitor Gonçalves de Faria, Marcela Guedes Matos Grespi, Lucas Alonso Rocha, Eduardo José Nassar

{"title":"AgNPs incorporated in Eu(III)-doped hydroxyapatite biomaterial: Spectroscopic, cytotoxicity, and antimicrobial investigation","authors":"Lauany Mazzon Pontes, João Vitor Gonçalves de Faria, Marcela Guedes Matos Grespi, Lucas Alonso Rocha, Eduardo José Nassar","doi":"10.1016/j.omx.2023.100286","DOIUrl":"10.1016/j.omx.2023.100286","url":null,"abstract":"<div>This study aimed to synthesize and to characterize hydroxyapatite with antimicrobial action. For the synthesis, the precursors calcium nitrate and phosphoric acid were employed; europium(III), 1 % w/w in relation to calcium(II), was used as spectroscopic probe, to investigate structural alterations. Silver nanoparticles, as antimicrobial agents, were added to the resulting material. Formation of the hydroxyapatite phase was confirmed by X-ray diffraction and vibrational spectroscopy in the infrared region. Incorporation of silver nanoparticles in the material was confirmed by electronic absorption spectroscopy in the ultraviolet–visible region, through the absorption band at approximately 400 nm. Scanning electron microscopy revealed that the material had adequate morphology to induce bone formation. The excitation, emission, and lifetime measurements of the structural probe, europium(III), showed that the hydroxyapatite unit cell had two symmetry sites. Cytotoxicity evaluation in human cells showed that the material was toxic at concentrations above 1250 μg/mL. At 2000 ppm, the material displayed antimicrobial activity against E. coli, but the maximum evaluated concentration was insufficient to verify activity against S. aureus. Therefore, hydroxyapatite bearing silver nanoparticles is a promising material for application in the medical area.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"21 ","pages":"Article 100286"},"PeriodicalIF":0.0,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000608/pdfft?md5=70cc4649d69af3dd4d6ceb894e73fc24&pid=1-s2.0-S2590147823000608-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138993806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Photoluminescence and X-ray induced scintillation in Gd3+-Tb3+ co-doped fluoride-phosphate glasses, and derived glass-ceramics containing NaGdF4 nanocrystals 掺杂 Gd3+-Tb3+ 的氟磷酸盐玻璃和含有 NaGdF4 纳米晶体的衍生玻璃陶瓷中的光致发光和 X 射线诱导闪烁

Optical Materials: X Pub Date : 2023-12-17 DOI: 10.1016/j.omx.2023.100288

Gustavo Galleani , Thiago A. Lodi , Robin L. Conner , Luiz G. Jacobsohn , Andrea S.S. de Camargo

{"title":"Photoluminescence and X-ray induced scintillation in Gd3+-Tb3+ co-doped fluoride-phosphate glasses, and derived glass-ceramics containing NaGdF4 nanocrystals","authors":"Gustavo Galleani , Thiago A. Lodi , Robin L. Conner , Luiz G. Jacobsohn , Andrea S.S. de Camargo","doi":"10.1016/j.omx.2023.100288","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100288","url":null,"abstract":"<div>The glass system (50NaPO3–20BaF2–10CaF2–20GdF3)-xTbCl3 with x = 0.3, 1, 3, 5, and 10 wt % was investigated. We successfully produced transparent glass ceramic (GC) scintillators with x = 1 through a melt-quenching process followed by thermal treatment. The luminescence and crystallization characteristics of these materials were thoroughly examined using various analytical methods. The nanocrystallization of Tb3+-doped Na5Gd9F32 within the doped fluoride-phosphate glasses resulted in enhanced photoluminescence (PL) and radioluminescence (RL) of the Tb3+ ions. The GC exhibited an internal PL quantum yield of 33 % and the integrated RL intensity across the UV-visible range was 36 % of that reported for the commercial BGO powder scintillator. This research showcases that Tb-doped fluoride-phosphate GCs containing nanocrystalline Na5Gd9F32 have the potential to serve as efficient scintillators while having lower melting temperature compared to traditional silicate and germanate glasses.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"21 ","pages":"Article 100288"},"PeriodicalIF":0.0,"publicationDate":"2023-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000621/pdfft?md5=1f88c030d73d83352e028bbe6efd25e9&pid=1-s2.0-S2590147823000621-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138839069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Solar spectral management in space using lanthanide-based downshifting layers 利用镧系元素降频层进行空间太阳光谱管理

Optical Materials: X Pub Date : 2023-12-05 DOI: 10.1016/j.omx.2023.100280

Sandra F.H. Correia , Lianshe Fu , Paulo S. André , Rute A.S. Ferreira

{"title":"Solar spectral management in space using lanthanide-based downshifting layers","authors":"Sandra F.H. Correia , Lianshe Fu , Paulo S. André , Rute A.S. Ferreira","doi":"10.1016/j.omx.2023.100280","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100280","url":null,"abstract":"<div>Photovoltaic (PV) cells are still the most used energy generation devices for aerospace applications. Although multijunction solar cells represent the standard commercial technology for powering spacecraft, spacecraft companies are still using Si-based PV cells to decrease the cost of satellites at the expense of efficiency and energy generation losses. One of the limitations on solar energy conversion is the mismatch between the solar spectrum and the absorption of the PV technology in use. Thus, strategies to overcome this have been proposed, namely the use of luminescent downshifting layers (DSLs) which are very promising to shape the incident sunlight. In this sense, downshifting materials with absorption in the UV/blue spectral region have been privileged considering the solar spectrum in space environments (AM0 solar spectrum), in which the UV component is larger than that on Earth surface (AM1.5 solar spectrum). Here, we propose the use of Eu3+-doped di-ureasil organic-inorganic hybrid materials as DSLs to be used on large area Si-based PV cells (∼0.1 m2) for space applications. Electrical measurements on the PV cell, done before and after the deposition of the DSLs, confirm the positive effect of the coatings on the device performance, with a relative increase on the generated electrical power of ∼2.6 %. Here, we report, for the first time, a DSL specifically designed for space applications and with the largest active area reported so far.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"21 ","pages":"Article 100280"},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000542/pdfft?md5=274450eadd04003cee93049244f39b8b&pid=1-s2.0-S2590147823000542-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138548813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Active biosoluble composite material obtained by real-time LbL photoreduction of silver via light-based 3D printing 通过光基三维打印对银进行实时 LbL 光还原而获得的活性生物可溶性复合材料

Optical Materials: X Pub Date : 2023-12-05 DOI: 10.1016/j.omx.2023.100283

Alisson S. de Albuquerque , Elaine C.R. Vaz , Janaína V. dos Anjos , Petrus A. Santa-Cruz

{"title":"Active biosoluble composite material obtained by real-time LbL photoreduction of silver via light-based 3D printing","authors":"Alisson S. de Albuquerque , Elaine C.R. Vaz , Janaína V. dos Anjos , Petrus A. Santa-Cruz","doi":"10.1016/j.omx.2023.100283","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100283","url":null,"abstract":"<div>In this study, a silver-containing photopolymerizable resin was developed and synthesized to create an active biosoluble composite for various applications, including biomedical devices. The main goal was to investigate the properties of this material, which can be produced through real-time LbL (Layer-by-Layer) in situ silver photoreduction during resin photopolymerization. This process uses the 405 nm LEDs of an MSLA (Masked Stereolithography Apparatus) 3D printer. Characterization techniques reveal chemical changes caused by the photoreduction of silver as well as an improvement in physical properties attributed to the presence of metallic silver. The silver nanocomposite has the potential for applications such as 3D-printed antimicrobial structures for biomedicine and engineering. To demonstrate the application of the developed material, a PoC (Proof of Concept) of 3D printing of bioinspired microneedles is presented, aiming to contribute to methods of drug administration that bypass the stratum corneum without causing pain.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"21 ","pages":"Article 100283"},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000578/pdfft?md5=f38f70ef36f1331964079c56a582ebb9&pid=1-s2.0-S2590147823000578-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138577533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

CdTe quantum dots as fluorescent nanotools for in vivo glioblastoma imaging 碲化镉量子点作为荧光纳米工具用于体内胶质母细胞瘤成像

Optical Materials: X Pub Date : 2023-12-05 DOI: 10.1016/j.omx.2023.100282

Maria Aparecida Barreto Lopes Seabra , Luiz Gustavo Dubois , Eraldo Fonseca dos Santos-Júnior , Renata Virgínia Cavalcanti Santos , Antônio Gomes de Castro Neto , Alinny Rosendo Isaac , Adriana Fontes , Gunther Hochhaus , Belmira Lara da Silveira Andrade da Costa , Vivaldo Moura Neto , Beate Saegesser Santos

{"title":"CdTe quantum dots as fluorescent nanotools for in vivo glioblastoma imaging","authors":"Maria Aparecida Barreto Lopes Seabra , Luiz Gustavo Dubois , Eraldo Fonseca dos Santos-Júnior , Renata Virgínia Cavalcanti Santos , Antônio Gomes de Castro Neto , Alinny Rosendo Isaac , Adriana Fontes , Gunther Hochhaus , Belmira Lara da Silveira Andrade da Costa , Vivaldo Moura Neto , Beate Saegesser Santos","doi":"10.1016/j.omx.2023.100282","DOIUrl":"10.1016/j.omx.2023.100282","url":null,"abstract":"<div>Glioblastoma (GBM) is the most aggressive and infiltrating primary tumor of the central nervous system (CNS), showing a variety of mutations and a high degree of vascularity, cell polymorphism, and nuclear atypia. GBM treatment often recurs to surgical resection, but such protocol lacks efficacy since complete tumor removal is not entirely successful due to invasive cells that cannot be detected at the moment of the surgery. Here, we describe a new in vivo targeting and imaging method for GBM detection in an orthotropic mouse model using fluorescent CdTe quantum dots (CdTe QDs) conjugated to anti-glial fibrillary acidic protein (anti-GFAP). We conjugated and optimized red-emitting CdTe QDs to anti-GFAP to label GBM (U87 cell line) in vivo. The in vivo tumor growth was visualized by the hematoxylin and eosin staining and showed the successful delivery of GBM cells into the mouse brain parenchyma. CdTe/anti-GFAP QDs were injected into the tumor region, and their uptake by tumor cells was visualized by fluorescence microscopy, showing a specific dual labeling with vimentin-immunoreactive GBM. The results reported here provide new perspectives for using CdTe QDs in GBM detection, suggesting their potential application in imaging-guided surgery and a potential fluorescent tool to be applied in the monitoring of 3D tumor glial cultures.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"21 ","pages":"Article 100282"},"PeriodicalIF":0.0,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000566/pdfft?md5=ce82416f54a125bd51405a5561426de3&pid=1-s2.0-S2590147823000566-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138626372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Flexible photonics in carbon and glass fiber reinforced polymers for new multifunctionality: Exploring the advances, challenges, and opportunities 碳纤维和玻璃纤维增强聚合物中的柔性光子学，实现新的多功能性：探索进展、挑战和机遇

Optical Materials: X Pub Date : 2023-12-01 DOI: 10.1016/j.omx.2023.100277

Christopher Holmes , Janice Dulieu-Barton

{"title":"Flexible photonics in carbon and glass fiber reinforced polymers for new multifunctionality: Exploring the advances, challenges, and opportunities","authors":"Christopher Holmes , Janice Dulieu-Barton","doi":"10.1016/j.omx.2023.100277","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100277","url":null,"abstract":"<div>Flexible photonics, characterized by their planar design and integrated features, have surfaced as a promising technology to unlock new possibilities for multifunctionality within fiber reinforced polymer composite materials. A comprehensive review of current progress, challenges, and opportunities associated with flexible photonic integration into carbon and glass fiber reinforced polymers is provided. A systematic examination of the literature has revealed several flexible photonic technologies that have demonstrated potential for integration in composite components to monitor performance in manufacture, service, and reuse. The review highlights the advantages and limitations of the current state-of-the-art in flexible integrated photonics for making assessments of compatibility with carbon and glass fiber reinforced polymer structures. By examining proof-of-concept demonstrations, the improved performance and novel functionalities that can be achieved for industrial applications are identified. The challenges associated with the integration process, such as durability and scalability are discussed in the context of the manufacturing processes required to create composite components. The concept of integrating flexible photonics in composite structures is relatively new, hence the paper closes by highlighting opportunities for further research and development in this field.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"20 ","pages":"Article 100277"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000517/pdfft?md5=f2ca35da6b3f4eefcc40c90237cd107b&pid=1-s2.0-S2590147823000517-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138582234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

X-ray excited optical luminescence at Carnaúba, the Sirius X-ray nanoprobe beamline 天狼星 X 射线纳米探针光束线 Carnaúba 的 X 射线激发光学发光

Optical Materials: X Pub Date : 2023-12-01 DOI: 10.1016/j.omx.2023.100278

Verônica C. Teixeira , Joelson C. Silva , Francisco C.M. Silva , Rodrigo Szostak , Maria Gabriella D. Guaita , Leonardo M. Kofukuda , Antonio C. Piccino Neto , Anna P.S. Sotero , Itamar T. Neckel , Carlos A. Pérez , Douglas Galante , Hélio C.N. Tolentino

{"title":"X-ray excited optical luminescence at Carnaúba, the Sirius X-ray nanoprobe beamline","authors":"Verônica C. Teixeira , Joelson C. Silva , Francisco C.M. Silva , Rodrigo Szostak , Maria Gabriella D. Guaita , Leonardo M. Kofukuda , Antonio C. Piccino Neto , Anna P.S. Sotero , Itamar T. Neckel , Carlos A. Pérez , Douglas Galante , Hélio C.N. Tolentino","doi":"10.1016/j.omx.2023.100278","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100278","url":null,"abstract":"<div>This work presents the developments and initial results obtained using X-ray excited optical luminescence (XEOL) at the Carnaúba, the nanoprobe beamline from Sirius, the Brazilian 4th generation synchrotron source. XEOL is a highly important tool to study luminescence mechanisms and identify optical channels in various types of materials under X-ray irradiation. Using this capability combined with a nanoprobe, one can probe optical channels, for example, in heterogenous materials, and directly correlate them with chemical composition, oxidizing state of absorbers, structure and/or morphology in simultaneous studies. Carnaúba is composed by two experimental station and at the Tarumã station, the first entering in operation, it has been possible to investigate XEOL in the integrated and emission modes, and 2D images in hyperspectral mapping with submicrometric resolution. Herein, it is showed some examples of studies combining excitation energy, emission wavelength and emission intensity in 3D spectra, 2D imaging, and XEOL emission on the study of very sensitive samples that can be easily damaged by the probe. This work also highlights some of the upcoming developments that include the time-resolved and in situ experiments, this last one using microfluidic cells, and the improvement of the covered emission wavelength up to 1700 nm, which will open new opportunities for studying optical materials.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"20 ","pages":"Article 100278"},"PeriodicalIF":0.0,"publicationDate":"2023-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000529/pdfft?md5=805fbd50fb7595d2ee456ddece4090d0&pid=1-s2.0-S2590147823000529-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138582247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the optical properties of monoclinic Na3AlF6 and Na3AlF6:Mn4+ 单斜晶型Na3AlF6和Na3AlF6:Mn4+的光学性质

Optical Materials: X Pub Date : 2023-11-13 DOI: 10.1016/j.omx.2023.100276

Thomas Jansen, David Böhnisch, Florian Baur, Thomas Jüstel

{"title":"On the optical properties of monoclinic Na3AlF6 and Na3AlF6:Mn4+","authors":"Thomas Jansen, David Böhnisch, Florian Baur, Thomas Jüstel","doi":"10.1016/j.omx.2023.100276","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100276","url":null,"abstract":"<div>Mn4+ activated luminescent materials have attracted much attention as colour converters for light sources and displays. In particular, alkali metal hexafluorometallates, such as K2SiF6:Mn4+ or K2TiF6:Mn4+, emit light in the red spectral region if pumped by phosphor converted LEDs (pcLED). In accordance with Zhu et al. we applied the cation-exchange method in order to synthesize Mn4+ doped Na3AlF6. Na3AlF6:Mn4+ exhibits efficient red photoluminescence peaking at 627 nm, which can be assigned to the 2Eg → 4A2g intraconfigurational transition of Mn4+ ([Ar]3d.3 configuration) within the [MnF6]2- octahedra on the aluminum site in the cryolite host structure. Photoluminescence properties, such as temperature dependence of the PL intensity and luminescence lifetime are presented. Additionally, the band structure of the undoped host material has been treated with Density Functional Theory (DFT). The theoretical results have been evaluated experimentally with diffuse UV reflectance spectroscopy. Finally, luminous efficacy and color rendering values of simulated warm white emitting pcLEDs comprising a dichromatic phosphor blend employing Na3AlF6:Mn4+ as the red emitting component are calculated and compared to the performance of warm white emitting pcLEDs comprising K2SiF6:Mn4+ as red emitting component.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"20 ","pages":"Article 100276"},"PeriodicalIF":0.0,"publicationDate":"2023-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000505/pdfft?md5=9a93d8c05fee2a6ff79ffa8780bddcc5&pid=1-s2.0-S2590147823000505-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134656133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Adaptive guided stochastic optimization: A novel approach for fitting the theoretical intensity parameters for lanthanide compounds 自适应引导随机优化:拟合镧系化合物理论强度参数的新方法

Optical Materials: X Pub Date : 2023-10-18 DOI: 10.1016/j.omx.2023.100275

Carlos V. Santos-Jr. , Eduardo C. Aguiar , Albano N. Carneiro Neto , Renaldo T. Moura Jr.

{"title":"Adaptive guided stochastic optimization: A novel approach for fitting the theoretical intensity parameters for lanthanide compounds","authors":"Carlos V. Santos-Jr. , Eduardo C. Aguiar , Albano N. Carneiro Neto , Renaldo T. Moura Jr.","doi":"10.1016/j.omx.2023.100275","DOIUrl":"https://doi.org/10.1016/j.omx.2023.100275","url":null,"abstract":"<div>In this study, we introduce a state-of-the-art approach to enhance the fitting accuracy of theoretical intensity parameters in lanthanide spectroscopy. Lanthanide-based compounds play a pivotal role in a wide range of applications due to their distinctive photophysical characteristics. Theoretical understanding and computational descriptions are essential for advancing these applications. The Judd-Ofelt theory stands as a fundamental stone, offering insights into the luminescence exhibited by lanthanide compounds. Our methodology addresses the procedure of fitting charge factors (<math><mi>g</mi></math> in the Simple Overlap Model) and ligand effective polarizabilities (<math><msup><mrow><mi>α</mi></mrow><mrow><mo>′</mo></mrow></msup></math> in the Bond Overlap Model), quantities used for the determination of the intensity parameters (<math><msub><mrow><mi>Ω</mi></mrow><mrow><mi>λ</mi></mrow></msub></math>). We propose Adaptive Guided Stochastic Optimization (AGSO), a method that employs randomized initial points within predefined bounds for each variable. By iteratively updating variable bounds based on population statistics, AGSO systematically minimizes the error function with respect to experimental data. Extensive tests were conducted comparing AGSO with the well-established simulated annealing (SA) method. Remarkably, AGSO consistently outperformed SA, demonstrating its efficacy in fitting intensity parameters for various lanthanide compounds. Through AGSO, we offer a robust and efficient tool for the accurate study of lanthanide-based compounds, with broad implications for diverse applications.</div>","PeriodicalId":52192,"journal":{"name":"Optical Materials: X","volume":"20 ","pages":"Article 100275"},"PeriodicalIF":0.0,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2590147823000499/pdfft?md5=d22d8835b1345dd5b4291414ad0bac07&pid=1-s2.0-S2590147823000499-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92024618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0