Ruoxi Huang , Deyi Yao , Kaichen Sun , Qihang Liu , Zhonghua Xu , Rongqiu Lv , Teng Ma , Jun Chen
{"title":"Flexible quantum dots color conversion layer fabricated via laser direct writing technique for Micro-LED","authors":"Ruoxi Huang , Deyi Yao , Kaichen Sun , Qihang Liu , Zhonghua Xu , Rongqiu Lv , Teng Ma , Jun Chen","doi":"10.1016/j.jlumin.2024.120902","DOIUrl":"10.1016/j.jlumin.2024.120902","url":null,"abstract":"<div><p>With the continuous increase in research and market demand for display, Micro-light-emitting diode (Micro-LED) has become one of the current research hotspots in the display industry due to its outstanding performance in color, resolution, life, and energy consumption. In this study, all-inorganic perovskite quantum dots (QDs) were synthesized using a hot injection method and uniformly coated on the surface of a polyethylene terephthalate (PET) substrate. Subsequently, laser processing technology was used to pattern the QDs film, achieving precise pattern design. Even after bending the film 100 times, the peak intensity of photoluminescence could still reach over 50 % compared with that of unbending. We used these specially treated flexible QDs films as the color conversion layers to realize color conversion display of Micro-LED. This research provides a research direction for the development of new display technology.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120902"},"PeriodicalIF":3.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142272864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Observation of anomalous excitonic emission in V-doped WS2 QDs synthesized by hydrothermal method and subsequent mechanical exfoliation","authors":"Prarbdh Bhatt, Ashok Kumar Mondal, Nilanjan Halder","doi":"10.1016/j.jlumin.2024.120904","DOIUrl":"10.1016/j.jlumin.2024.120904","url":null,"abstract":"<div><div>This study focuses on synthesizing vanadium (V) doped 2H phase WS<sub>2</sub> via a facile hydrothermal method and subsequent liquid phase mechanical exfoliation of the material into QD-like nanostructures. An increment in dopant percentage from 1 % to 7 % red shifted the band gap of WS<sub>2</sub> from 4.15 eV to 3.78 eV. The nanostructures show electronic transition due to B, A, and defect-bound excitons and demonstrate modulation of excitonic behavior with V doping. Low V doping provides the WS<sub>2</sub> material with a reduced B/A excitonic peak intensity ratio because of the nonradiative pathways favoring the relaxation of high energy B excitons to A excitons. High V doping results in anomalous emission behavior marked by an increased B/A ratio, attributed to positive trion formation as a result of excess free hole concentration due to the p-type vanadium. The study suggests that V-doped WS<sub>2</sub> nanostructures hold potential for technological applications, particularly in spintronics and photonics, emphasizing the importance of engineering exciton dynamics in two-dimensional materials using p-type substitutional dopants.</div></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120904"},"PeriodicalIF":3.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142359503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Renping Cao , Minhong Wu , Bang Lan , Tengyu Huang , Jingheng Nie , Fangrui Cheng , Xiaohu Luo , Jing Wang
{"title":"Study on the properties of Sm3+-Doped CaTbAl3O7 phosphors","authors":"Renping Cao , Minhong Wu , Bang Lan , Tengyu Huang , Jingheng Nie , Fangrui Cheng , Xiaohu Luo , Jing Wang","doi":"10.1016/j.jlumin.2024.120898","DOIUrl":"10.1016/j.jlumin.2024.120898","url":null,"abstract":"<div><p>New single phase and adjustable emission phosphors have attracted a lot of attention because of the good luminous properties. In this work, Sm<sup>3+</sup> doped CaTbAl<sub>3</sub>O<sub>7</sub> phosphors are prepared in air by solid-state method. The crystal structure, concentration dependent spectra, lifetimes, and luminescence properties are investigated. Because of the 4<em>f</em><sup>8</sup> → 4<em>f</em><sup>7</sup>5<em>d</em><sup>1</sup> and 4<em>f</em> → 4<em>f</em> transitions of Tb<sup>3+</sup> ion, host (CaTbAl<sub>3</sub>O<sub>7</sub>) shows an excitation spectrum in the range of 220–520 nm under monitored at 544 nm and emits yellow-green light under excitation 248, 284, and 368 nm due to the <sup>5</sup>D<sub>4</sub> → <sup>7</sup>F<sub><em>J</em></sub> (<em>J</em> = 0, 1, 2, 3, 4, 5, and 6) transitions of Tb<sup>3+</sup> ion. CaTbAl<sub>3</sub>O<sub>7</sub>:Sm<sup>3+</sup> under monitored 598 nm contains the excitation spectral peaks of both CaTbAl<sub>3</sub>O<sub>7</sub> and Sm<sup>3+</sup> ion. With excitation at 368 nm, CaTbAl<sub>3</sub>O<sub>7</sub>:Sm<sup>3+</sup> glows orange-red light, its PL spectrum has both host (CaTbAl<sub>3</sub>O<sub>7</sub>) and Sm<sup>3+</sup> ion contributing, and the chromaticity coordinates are about (0.5499, 0.4351). Under excitation 402 nm, the red-orange emission of CaTbAl<sub>3</sub>O<sub>7</sub>:Sm<sup>3+</sup> is only the contribution of Sm<sup>3+</sup> ion and the chromaticity coordinates are about (0.5823, 0.4168). The energy transfer process from Tb<sup>3+</sup> in host (CaTbAl<sub>3</sub>O<sub>7</sub>) to Sm<sup>3+</sup> ions can be confirmed via the spectral properties. We explain the luminous mechanism of CaTbAl<sub>3</sub>O<sub>7</sub>:Sm<sup>3+</sup> by the energy level diagrams of Tb<sup>3+</sup> and Sm<sup>3+</sup>.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120898"},"PeriodicalIF":3.3,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142241832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guowang Wu , Gen Li , Dixi Ke , Xi Li , Min Zeng , Yongming Hu , Haoshuang Gu , Yuebin Li
{"title":"Synthesis and photoluminescence properties of novel far-red emitting garnet phosphor Y3Ga3MgSi(1-y)GeyO12:Mn4+","authors":"Guowang Wu , Gen Li , Dixi Ke , Xi Li , Min Zeng , Yongming Hu , Haoshuang Gu , Yuebin Li","doi":"10.1016/j.jlumin.2024.120897","DOIUrl":"10.1016/j.jlumin.2024.120897","url":null,"abstract":"<div><p>In this paper, a novel far-red emitting garnet-structured phosphor, Y<sub>3</sub>Ga<sub>3</sub>MgSiO<sub>12</sub>:Mn<sup>4+</sup>, was synthesized using the traditional solid-state reaction method. The prepared Y<sub>3</sub>Ga<sub>3</sub>MgSiO<sub>12</sub>:Mn<sup>4+</sup> phosphor exhibits a broad excitation band in the range of 250–600 nm and emits bright far-red light in the wavelength range of 630–710 nm, with a peak at 670 nm when excited at 354 nm. The optimal doping concentration of Mn<sup>4+</sup> is approximately x = 0.006. Beyond this concentration, luminescence quenching occurs due to energy transfer between Mn<sup>4+</sup> ions caused by dipole-dipole interactions. The effect of cation substitution on the photoluminescence properties of Y<sub>3</sub>Ga<sub>3</sub>MgSi<sub>(1-y)</sub>Ge<sub>y</sub>O<sub>12</sub>:0.01Mn<sup>4+</sup> phosphors was studied, revealing that the substitution of Ge<sup>4+</sup> ions can systematically influence the luminescence of Mn<sup>4+</sup>. The Y<sub>3</sub>Ga<sub>3</sub>MgSiO<sub>12</sub>:0.01Mn<sup>4+</sup> phosphor exhibits excellent color purity, and its emission spectrum matches well with the absorption spectra of photosensitive pigments P<sub>R</sub> and P<sub>FR</sub>. The temperature-dependent emission spectra of Y<sub>3</sub>Ga<sub>3</sub>MgSi<sub>(1-y)</sub>Ge<sub>y</sub>O<sub>12</sub>:0.01Mn<sup>4+</sup> phosphors were studied, and the activation energy was calculated. The substitution of Ge<sup>4+</sup> ions can improve the thermal stability of the samples. These outstanding photoluminescence properties suggest that Y<sub>3</sub>Ga<sub>3</sub>MgSiO<sub>12</sub>:Mn<sup>4+</sup> phosphor has application potential in pc-WLEDs and indoor plant cultivation pc-RLEDs. The findings of this work provide ideas for the design of high performance Mn<sup>4+</sup> activated phosphors.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120897"},"PeriodicalIF":3.3,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yujun Wang , Wenxuan Han , Zeyu Sun , Wenzhen Diao , Xin Xie , Guoqiao Li , Zhenglong Zhang , Zhengkun Fu , Hairong Zheng
{"title":"Photon avalanche effect and spectral control of single LiYF4:Yb3+/Pr3+microparticle","authors":"Yujun Wang , Wenxuan Han , Zeyu Sun , Wenzhen Diao , Xin Xie , Guoqiao Li , Zhenglong Zhang , Zhengkun Fu , Hairong Zheng","doi":"10.1016/j.jlumin.2024.120893","DOIUrl":"10.1016/j.jlumin.2024.120893","url":null,"abstract":"<div><p>Photon avalanche is a special phenomenon of upconversion that the luminescence emission intensity exhibits a significant nonlinear response to the excitation power. Traditional photon avalanche is typically observed in bulk materials, which is not enough to meet requirements of modern techniques as it expect smaller in size and stronger in signal response. In this study, photon avalanche effect is obtained from single LiYF<sub>4</sub>: Yb<sup>3+</sup>/Pr<sup>3+</sup> microparticle. The emission intensity demonstrates a 16-order nonlinear coefficient with excitation intensity change under 835 nm laser excitation. By utilizing the plasmonic effect of noble metal nanoparticles, we successfully modulate the photon avalanche of the particle. Obvious reduction in the threshold of photon avalanche is detected when plasmonic gold nanorods are assembled to the surface of LiYF<sub>4</sub>: Yb<sup>3+</sup>/Pr<sup>3+</sup> microparticle.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120893"},"PeriodicalIF":3.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wenqi Xia , Feng Du , Qianqian Zhao, Longsheng Du, Zhihua Leng, Zuobin Tang
{"title":"Realization of narrow-band blue emission based on structurally engineering-designed Bi3+-doped phosphors","authors":"Wenqi Xia , Feng Du , Qianqian Zhao, Longsheng Du, Zhihua Leng, Zuobin Tang","doi":"10.1016/j.jlumin.2024.120896","DOIUrl":"10.1016/j.jlumin.2024.120896","url":null,"abstract":"<div><p>The exploration of efficient narrowband emission phosphors is crucial for white light-emitting diodes (WLEDs) in high-performance backlighting applications. Up to now, the discovery of narrow-band Bi<sup>3+</sup>-doped phosphors for emerging applications remains challenging because Bi<sup>3+</sup> typically exhibits broadband emission properties. A novel narrow-band blue phosphor (Ca<sub>4</sub>SnGe<sub>3</sub>O<sub>12</sub>:Bi<sup>3+</sup>) was successfully synthesized, benefiting from the highly symmetric crystal environment and tightly connected rigid structure of the garnet structure. The phosphor demonstrates broad excitation in the near-ultraviolet (n-UV) region and emits narrowband blue light at 442 nm (FWHM = 36 nm) with a color purity of 94.7 %. In this paper, the assignment of different luminescence centers and the use of Zr/Hf to partially replace Sn to enhance luminescence performance are studied. The reasons for the consequent changes in luminescence behavior are explained in detail. The use of narrowband commercial red K<sub>2</sub>SiF<sub>6</sub>:Mn<sup>4+</sup>, green β-Sialon:Eu<sup>2+</sup>, and synthetic blue luminescent materials as RGB emitters covered 81 % of the National Television System Committee (NTSC) color space, demonstrating great potential for liquid-crystal-display (LCD) backlight use.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120896"},"PeriodicalIF":3.3,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142232335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spectroscopic analysis of La2(WO4)3:Tb3+ phosphor and the delayed concentration quenching of 5D4 →7FJ emission","authors":"Bibily Baby, Sajan Thomas, Jifi Jose, Manju Gopinath, P.R. Biju, Cyriac Joseph","doi":"10.1016/j.jlumin.2024.120895","DOIUrl":"10.1016/j.jlumin.2024.120895","url":null,"abstract":"<div><p>Trivalent terbium ion doped lanthanum tungstate (La<sub>2-x</sub>Tb<sub>x</sub>(WO<sub>4</sub>)<sub>3</sub>; x = 0.6,1.0,1.4) and terbium tungstate (Tb<sub>2</sub>(WO<sub>4</sub>)<sub>3</sub>) phosphors were successfully synthesized via optimized microwave-assisted co-precipitation technique. The phase purity and crystallinity of the prepared samples were confirmed using the powder XRD technique. The photoluminescence studies revealed a quenching-free emission up to 70 % of Tb<sup>3+</sup> doping concentration, even though the emission intensity slightly decreases under host excitation since it becomes less relevant at higher doping concentrations. The experimental and calculated oscillator strengths were evaluated using absorption data and further used to quantify the Judd - Ofelt (JO) intensity parameters, which appeared in a trend of Ω<sub>2</sub>>Ω<sub>4</sub>>Ω<sub>6</sub> for all samples. As a theoretical approach to assure the excellency of the tungstate host, the radiative parameters were calculated from the emission data using the JO analysis technique. The dominance in the values of stimulated emission cross section and gain bandwidth corresponding to <sup>5</sup>D<sub>4</sub>→<sup>7</sup>F<sub>5</sub> transition of Tb<sup>3+</sup> ion of lanthanum tungstate proclaims it as an excellent green phosphor. Hence, the less susceptibility of the tungstate host towards concentration quenching is confirmed in the present work.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120895"},"PeriodicalIF":3.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Navya Sara Kuriyan , P.S. Ghosh , M. Parvathy , A. Arya , Sabeena M
{"title":"Unraveling the role of crystal structural variations in modifying the luminescence properties of CMS: Eu3+ phosphor","authors":"Navya Sara Kuriyan , P.S. Ghosh , M. Parvathy , A. Arya , Sabeena M","doi":"10.1016/j.jlumin.2024.120894","DOIUrl":"10.1016/j.jlumin.2024.120894","url":null,"abstract":"<div><p>Pristine and europium doped calcium magnesium silicate (CMS and CMS: Eu<sup>3+</sup>) phosphor having akermanite (Ca<sub>2</sub>MgSi<sub>2</sub>O<sub>7</sub>), monticellite (CaMgSiO<sub>4</sub>) and merwinite (Ca<sub>3</sub>MgSi<sub>2</sub>O<sub>8</sub>) phases are synthesized via solid state reaction method. The modification of photoluminescence properties such as emission intensity, decay time and quantum yield (QY) due to the variation of the crystal structure, local site symmetry and coordination geometry of akermanite, monticellite and merwinite phases are studied. The merwinite phase is optimized at an annealing temperature of 900 °C, whereas monticellite phase is at 1100 °C. The agglomerated morphology changes to particle formation as the annealing temperature changes from 900 °C to 1100 °C. The lattice parameters and site preference of Eu<sup>3+</sup> ions are determined using Density Functional Theory (DFT) calculations. The analysis of lattice expansion, formation enthalpy (<span><math><mrow><msub><mrow><mo>Δ</mo><mi>H</mi></mrow><mi>f</mi></msub></mrow></math></span>) and mixing energy (<span><math><mrow><msub><mrow><mo>Δ</mo><mi>H</mi></mrow><mi>m</mi></msub></mrow></math></span>) reveal the preference of Eu<sup>3+</sup> occupation in the Ca<sup>2+</sup> cationic site over Mg<sup>2+</sup> for all three phases. The blueshift and redshift of Mg-O and Ca-O stretching in the Fourier Transform Infra-Red (FTIR) analysis agree with the DFT calculation. UV–visible spectra analyses reveal a modification in optical bandgap with Eu<sup>3+</sup> addition. The highest intensity <sup>5</sup>D<sub>0</sub>→<sup>7</sup>F<sub>2</sub> induced electric dipole (ED), hypersensitive transition indicates the preference of Eu<sup>3+</sup> ions in a non-inversion center for all the phases. This agrees with the higher <span><math><mrow><msub><mi>Ω</mi><mn>2</mn></msub></mrow></math></span> values from Judd-Ofelt (J-O) parameter calculations and local site symmetry analysis of DFT-optimized structures. The monticellite phase exhibits maximum crystal field splitting due to its octahedral geometry, whereas the akermanite phase, with its distinct dodecahedral geometry, displays maximum emission intensity, an extended decay time, and the highest quantum yield (QY). The modification of photoluminescence properties of the three phases is analyzed in detail based on the coordination geometry and the distortion in local sites due to Eu<sup>3+</sup> doping in the Ca and Mg sites. CIE color chromaticity analysis confirms the orange-red emission with 91.94 %, 90.88 % and 90.24 % color purity for akermanite, monticellite and merwinite phases respectively. Hence, the present study throws light on the potency of the akermanite phase of CMS: Eu<sup>3+</sup> phosphor with 70 % QY as the optimal matrix for Eu<sup>3+</sup> ions over monticellite and merwinite host matrices.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120894"},"PeriodicalIF":3.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T.S. Shamirzaev , D.R. Yakovlev , D. Kudlacik , C. Harkort , M.A. Putyato , A.K. Gutakovskii , M. Bayer
{"title":"Thin Ga(Sb,P)/GaP quantum wells with indirect band gap: Crystal structure, energy spectrum, exciton recombination and spin dynamics","authors":"T.S. Shamirzaev , D.R. Yakovlev , D. Kudlacik , C. Harkort , M.A. Putyato , A.K. Gutakovskii , M. Bayer","doi":"10.1016/j.jlumin.2024.120888","DOIUrl":"10.1016/j.jlumin.2024.120888","url":null,"abstract":"<div><p>Heterostructures with thin GaSb layers embedded in a GaP matrix are studied by transmission electron microscopy as well as steady-state and transient photoluminescence. For a single, one monolayer thick deposition with subsequent overgrowth, nonmonotonic Sb segregation results in self-organized Ga(Sb,P) double-quantum well (QW) formation. One QW is positioned deep in GaP at the designated place according to the heterostructure design, and the other QW is in the near surface region after 40 monolayers of GaP overgrowth. Both QWs are characterized by an indirect band gap. The band alignment in the QWs is identified as type I. In spite of the long (up to milliseconds) exciton lifetimes in the QWs in combination with the electron <em>g</em> factor of +2, the emission of the QWs demonstrates a low circular polarization degree in longitudinal magnetic fields as strong as 10 T. We demonstrate that the electron spin polarization in the Ga(Sb,P)/GaP heterostructure subject to a magnetic field occurs in the GaP layer, and spin-polarized charge carriers captured in the QWs store their spin orientation up to the millisecond time range, indicating very long spin relaxation times for the strongly localized electrons in the Ga(Sb,P)/GaP QWs.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120888"},"PeriodicalIF":3.3,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142241831","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Synthesis, structural characterization and intense far-red luminescence of Mn4+ -activated SrLaMgTa1-yAlyO6 oxide phosphors","authors":"Jiayue Wu , Yufeng Mao , Jiye Wang, Shikao Shi","doi":"10.1016/j.jlumin.2024.120892","DOIUrl":"10.1016/j.jlumin.2024.120892","url":null,"abstract":"<div><p>The transition metal Mn<sup>4+</sup> activated phosphors have attracted increasing attention due to the potential uses in phosphor-converted lighting emitting diodes (LEDs). Herein, the far-red emitting SrLaMgTa<sub>1-y</sub>Al<sub>y</sub>O<sub>6</sub>:Mn<sup>4+</sup> (y = 0−0.15) oxide phosphors were successfully synthesized by the high-temperature solid state reaction, in which the Mn<sup>4+</sup> acted as an activator. The monoclinic double perovskite crystal structure, chemical composition, and 4+ state of activator Mn were confirmed by means of X-ray diffraction Rietveld refinement, scanning electron microscopy elemental mapping, and X-ray photoelectron spectroscopy. The optical properties were characterized with photoluminescence excitation and emission spectra, temperature-dependent emission spectra, and electroluminescence spectra. The excitation spectra are interweaved with the ligand-to-metal charge transfer band of Mn−O and intrinsic transitions (<sup>4</sup>A<sub>2g</sub>→<sup>4</sup>T<sub>1g</sub>, <sup>4</sup>A<sub>2g</sub>→<sup>2</sup>T<sub>2g</sub>, and <sup>4</sup>A<sub>2g</sub>→<sup>4</sup>T<sub>2g</sub>) of Mn<sup>4+</sup>, locating at the ultraviolet and blue light region. The emission spectra mainly contain a dominant far-red emission band from 650 to 775 nm with peaks at 695 and 708 nm, which are ascribed to the <sup>2</sup>E<sub>g</sub>→<sup>4</sup>A<sub>2g</sub> transition of Mn<sup>4+</sup>. Moreover, the cationic substitution strategy with tiny Al<sup>3+</sup> occupying Ta<sup>5+</sup> octahedral site, promotes the improvement of luminescence intensity and optical thermal stability. The quantum yield of optimal phosphor reaches 88.2 % and the fluorescence intensity at 373 K (100 °C) retains 83.4 % in respect to that at ambient temperature, implying the phosphor with intense and thermally stable luminescence. The phosphor is packaged with 365 nm chip to fabricate an LED device, and the electroluminescence result is quite consistent with the photoluminescence, matching well with the absorption spectrum of the phytochrome. The Mn<sup>4+</sup> activated oxide phosphors with intense far-red emission are promising for plant cultivation lighting.</p></div>","PeriodicalId":16159,"journal":{"name":"Journal of Luminescence","volume":"277 ","pages":"Article 120892"},"PeriodicalIF":3.3,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142168499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}