JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Shiyu Xiao,Shian Xie,Manbo Zhang,Shengmin Hu,Marc Adape,Jian Wang,Xinhui Zhang,Yongqin Wei,Wei Chen
Here we report two luminescent copper complexes with different structures and luminescent properties, the blue-green [CuI(dmpyHS) (PPh 3 ) 2 ]⸱CH 3 CN (CuPy-PPh 3 ) and the red [Cu 6 (dmpyS) 6 ]⸱H 2 O (CuPy). When the blue-green light (CuPy-PPh 3 ) is heated to above 147 °C, it loses the phosphine-containing ligand, PPh 3 , and turns into CuPy and instead emits red light. Many luminescent complexes show the change of luminescence properties when the temperature is lower than room temperature , while the luminescence change of CuPy-PPh 3 occurs during the heating process above room temperature. Even more interesting, the luminescence wavelength transition span is large, from blue-green light emission at 490 nm to red light at 676 nm. The luminescence of the two copper complexes covers the three primary colors of red, green and blue required for the formation of white light emitting diodes WLEDs, which has potential in the development of non-rare earth phosphor white color displays. The integration of CuPy-PPh 3 and CuPy on a 395 nm near-ultraviolet chip can assemble WLEDs with good white light properties, which provides a new way for the construction of rare earth-free phosphor WLEDs. The synthesis of the two luminescent copper complexes is simple and environmentally friendly. Even though the structures of two copper complexes have been reported, the synthesis methods are different from those in the related literature and the luminescence properties of these complexes have never been described previously. The red emission copper complex CuPy is obtained by the thermal conversion of the blue-green emission copper complex CuPy-PPh 3 , which is a new phenomenon discovered for the first time in this work.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Yuhang Kuang,Jiance Jin,Gaochao Liu,Weibin Chen,Zhiguo Xia
Single-phase white-light emitters in the lighting technology overcome the challenges of re-absorption and color shift. However, achieving the broadband white emission in single-phase phosphor remains a challenge. Here, crystallized KBaScSi 3 O 9 :Eu 2+ (KBSSO:Eu 2+ ) glass-ceramics (GC) with abundant cationic sites have been developed and an ultra-broad emission band ranging from 460 to 800 nm have been found, in which the asymmetric green emission is ascribed to the Eu 2+ ions in [KO 8 ] and [BaO 7 ] polyhedra, while the red emission centered at 620 nm is originated from Eu 2+ ions in [ScO 6 ] sites. The optimized GC-converted white LED (WLED) exhibits a high color rendering index ( R a = 89.8) and low correlated color temperature (CCT = 4241 K). Moreover, the encapsulant-free GCc-WLED can operate continuously under high drive currents. This work paves the way for the design and future development of single-phase high-power white light sources.
研究领域:
材料科学
·
光学工程
·
照明技术
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2020
·Vol. 7
·期 22
·4477-4487
·
IF 5.958
Xiang-Ling Lin,Bin Chen,You-Ren Huang,Kai-Yue Song,Pan-Ke Zhou,Lu-Lu Zong,Hao-Hong Li,Zhi-Rong Chen,Rong Jiang
The design of single-component broadband photoemitters with high stability is imperative for the development of next-generation WLEDs. In this work, 1D cationic haloplumbate chains and rigid luminescent naphthalene dicarboxylate (2,6-ndc) with a larger conjugated system were used to construct crystalline single-component broadband photoemitters, i.e. formulated as [(Pb4X2)(ndc)4·A2]n (X = Cl, Br, and I, A = (CH3)3NH+ and (CH3)2NH2+). These hybrids are 3D networks built from flexible 1D cationic (Pb4X2)6+ chains and rigid 2,6-naphthalene dicarboxylic acid ligands. The variation of halogen atoms from Cl to Br/I with higher polarity can switch the holo-directed geometry to the hemi-directed geometry with different distorted degrees. The larger conjugated system of 2,6-ndc leads to strong individual blue adsorptions and emissions. In particular, the Br- and I-analogues with hemi-directed geometries can give rise to additional red emissions, corresponding to the presence of stereochemical activities of Pb centers. Consequently, Br- and I-analogues are white-light emitters containing red emissions stemming from deformable haloplumbate and blue emissions originating from luminescent naphthalene motifs. Interestingly, haloplumbate-based emissions are thermally tunable, and those of naphthalene are generally inactive to thermal stimulus. As a result, tunable emissions from blue/white to yellow can be achieved. The higher quantum yield of Br-analogues can be assigned to their worse haloplumbate connectivity, which can enhance the electron–phonon coupling. In all, the combination of flexible haloplumbate chains with larger π-conjugated fluorophores is an efficient strategy for the construction of tunable broadband photoemitters.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2021
·
IF 5.165
Yijia Liu,Gengxin Zhang,Junben Huang,Xiaoma Tao,Guihua Li,Gemei Cai
Single-phase white-emission phosphors possess a judicious usage potential in phosphor-converted white-light-emitting diodes (WLEDs). Recently, numerous efforts have been made toward the development of new patterns of white-emitting phosphors that achieve excellent quantum yield, superior thermal stability, and applaudable cost effectiveness of WLEDs. Finding suitable single-component white phosphor hosts to provide an ideal local environment for activators remains urgent. Inspired by the original discovery of the promising host MgIn2(P2O7)2 (MIP) and its structural dependence on alkali-metal cations, we synthesized a brand-new phosphor host, SrIn2(P2O7)2 (SIP), via the traditional solid-state reaction. Its crystal structure was determined using an ab initio analysis and the Rietveld method. It belongs to a monoclinic unit cell with the space group C2/c. Besides, SIP exhibits a special layered three-dimensional framework in which the monolayer [SrO10]∞ was surrounded by a bilayer [In2P4O14]∞ made of the InO6 octahedra and P2O7 groups. A series of pure SIP:Tm3+,Dy3+ phosphors with tunable blue–white–yellow emission were prepared by adjusting the dopant concentration and utilizing the Tm3+–Dy3+ energy transfer. The daylight-white-emitting phosphor SIP:0.01Tm3+,0.04Dy3+ (the correlated color temperature is 4448 K) exhibits an abnormal thermal antiquenching property, and the emission intensity of 423 K reaches 103.7% of the initial value at 300 K. On the basis of the temperature-dependent lattice evolution and microenvironment analysis, the reduction of β and lattice distortion can lead to lower asymmetry of the activators and benefit the compensation of trapped-electron thermal activation. In this work, an integration study was carried out on the crystal structure of the new matrix, the occupation of the luminescent center, the interaction of different activators in the host, and the distortion degree of the local structure for the activators, which is of great practical sense for producing a novel single-matrix white phosphor possessing superior thermal endurance for UV-light-stimulated WLEDs.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2022
·
IF 5.436
Haiping Xu,Zhizhuan Zhang,Xuehua Dong,Ling Huang,Hongmei Zeng,Zhien Lin,Guohong Zou
Organic–inorganic hybrid metal halides (OIMHs) exhibiting white-light emission are a splendid class of emitters and are regarded as desired phosphors for solid-state lighting applications. Here we report a single-component white-light-emitting hybrid metal halide, namely, [C6H7ClN]CdCl3 (C6H7ClN = 4-(chloromethyl)pyridinium), which features a corrugated 1D anionic double chain composed of edge-shared CdCl6 octahedrons and exhibits broadband white-light emission with a photoluminescence quantum yield of 12.3% under 365 nm UV light irradiation. Density functional theory calculations and temperature-dependent emission spectral analysis unveil that the broadband emission of [C6H7ClN]CdCl3 is ascribed to self-trapped excitons. Moreover, a single-component white-light-emitting diode device with a correlated color temperature of 5214 K and color rendering index of 83.7 can be fabricated via coating [C6H7ClN]CdCl3 on a 365 nm UV light-emitting diode chip. Such a promising luminescent material provides guidance for the design and synthesis of OIMHs with unique structures and desired properties.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Shuai Wei,Zhijun Li,Zeyu Lyu,Dashuai Sun,Sida Shen,Jianhui Wang,Chengyu Zhuo,Hongpeng You
In this work, we provide a paradigm how to realize white light emission by utilizing the energy transfer from the Bi 3+ to Eu 3+ ions. First, a novel Bi 3+ activated phosphor set of highly oxygen-deficient perovskite derivatives (Ba 3 YGa 2 O 7.5 , BYGO) were synthesized through the conventional high-temperature solid-state method. The crystal structure was confirmed by Rietveld refinement . Then, Eu 3+ was introduced to the phosphor composition to construct energy transfer pathway with Bi 3+ . The emission color of the BYGO:Bi 3+ ,Eu 3+ phosphors can be changed from cyan to white and orange-red by altering the Bi 3+ /Eu 3+ doping ratio. The energy transfer from the Bi 3+ to Eu 3+ ions was ascribed to dipole-dipole interaction. Finally, a single-component WLED device with a color-rendering index of 84.9 was successfully prepared by employing a near-ultraviolet chip and the BYGO:Bi 3+ ,Eu 3+ phosphors. This work not only indicates that the as-prepared BYGO:Bi 3+ ,Eu 3+ phosphors are a potential candidate for near-ultraviolet WLED, but also demonstrated that energy transfer is an avenue for single-phased white light emission.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Deyuan Yang,Ruirui Cui,Chaoyong Deng
Recently, the splendid strategy of co-doping ns2 electron configuration ions with rare-earth ions in all-inorganic lead-free halide double perovskites has been proposed to overcome the weak absorption cross-section of the f–f transition of rare-earth ions and achieve efficient white emission. But few of them can really provide effective red emission in lead-free halide double perovskites, despite the wide variety of rare-earth ions, and lead-free halide double perovskites with co-doping rare-earth ions and doping ns2 electron configuration ions usually exhibit an unsatisfactory color rendering index due to the narrow characteristic emission peaks of rare-earth ions. To address this issue, Mn2+ ions with red wide peak emission were introduced into Cs2NaScCl6 simultaneously with Tb3+ ions and Sb3+ ions in this work. The white light emission was observed in Cs2NaScCl6:0.01Sb3+,0.12Tb3+,0.07Mn2+ under 336 nm excitation because the presence of energy transfer from Sb3+ ions to Mn2+ and Tb3+ ions enhances fluorescence performances of Mn2+ and Tb2+. The temperature-dependent spectrum of Cs2NaScCl6:0.01Sb3+,0.12Tb3+,0.07Mn2+ shows that it exhibits a stable white emission in the temperature range of 298–398 K, and it's emission intensity at 398 K only decreases by less than 18% of the initial intensity (at 298 K). Excitingly, WLED devices with a quite high color rendering index of 93.6, which is one of the best in lead-free halide double perovskites, and nearly standard white light CIE coordinates of (0.3425, 0.3435), have been fabricated by using Cs2NaScCl6:0.01Sb3+,0.12Tb3+,0.07Mn2+ and a 340 nm LED chip and can maintain a good white color stability at different working times and currents. These results indicate that Cs2NaScCl6:Sb3+,Tb3+,Mn2+ is an outstanding candidate for WLED applications.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Yi Zhang,Cuiping Zhou,Qifeng Zhang,Pengfei Yin,Xiyuan Sun,Kaiming Wang,Jian Wang,Xing Feng
In this paper, a synthesized material change from perovskite-layer-structured La 2 Ti 2 O 7 to perovskite type LaTiO 3 induced by Li 2 CO 3 addition was observed. The [TiO 6 ] octahedral site symmetry and particle uniformity showed an obvious variation with the change from La 2 Ti 2 O 7 to LaTiO 3 . A broadband far-red emission from 670 to 780 nm emerged when Mn 4+ , Li + ions were co-doped. Furthermore, (Mn 4+ , Li + ) co-doped LaTiO 3 phosphor can be effectively excited by near-UV and blue lights, which is suitable for combining with commercial InGaN LED chips. The LaTiO 3 :0.4%Mn 4+ , 150%Li + phosphor exhibited a high quantum efficiency of 71.1% and a good thermal stability with emission intensity retained 65% at 423 K. Finally, a LED device was fabricated with the LaTiO 3 :0.4%Mn 4+ , 150%Li + phosphor, which matches well with the absorption of photochrome of P FR and shows a good potential for use in agricultural cultivation fields.
研究领域:
材料科学
·
农业科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Yi Zhang,Peng Wang,Bibo Lou,Shengjie Niu,Haonian Bai,Dan Zhang,Chong-Geng Ma
To fulfill the escalating demand for high-quality white lighting, the exploration of novel and advanced luminescent materials holds a significant role in addressing the issues of reabsorption, color bleaching and deviation in modern WLED solid-state lighting technology based on phosphor-converted materials. In this research, a series of novel Bi 3+ -activated gallium-germanate luminescent materials Sr 2 Ga 2 GeO 7 (SGGO): Bi 3+ were synthesized by means of the classic high-temperature solid-phase method. A comprehensive exploration of their crystal structure, electronic structure, and optical transition properties were conducted through a combined experimental and theoretical calculation analysis. The research outcomes suggest that Bi 3+ , which is prone to occupying Sr sites, shows a remarkable blue emission with a peak at approximately 450 nm throughout the entire spectral range from near ultraviolet (UV) to near infrared when excited at 315 nm, and this is attributed to the 3 P 1 → 1 S 0 transition. Additionally, by devising an efficient energy transfer strategy from Bi 3+ to Eu 3+ , single-component white light can be attained by merely adjusting the doping concentration of Eu 3+ in the SGGO: Bi 3+ , Eu 3+ co-activation system. Eventually, devices packaged based on 310 nm ultraviolet chips also demonstrate the potential application of the synthesized material in WLEDs. These findings contribute to a deeper understanding of the luminescence and energy transfer mechanisms of Bi 3+ -activated systems, and also offer essential guidance for the advancement of high-performance Bi 3+ -doped advanced light-conversion materials and effective materials for various applications demanding enhanced light conversion properties.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2019
·Vol. 30
·期 46
·465201
·
IF 3.399
Congcong Wang,Dingke Xue,Xinyu Shen,Hua Wu,Yu Zhang,Haining Cui,William W Yu
Perovskite white light-emitting devices (WLEDs) without intercalation layers have not been achieved due to the ion exchange. Although the intercalation layers prevent ion exchange between perovskite nanocrystals (NCs), it also creates a new problem of charge imbalance and the structure becomes more complex. In this study, blue emitting ZnCdS/ZnS NCs with high quantum yield and stability are introduced to work with the yellow emission from CsPb(Br/I)3 perovskite NCs for WLEDs. The WLEDs are constituted of ITO/ZnO/PEI/ZnCdS/ZnS NCs/CsPb(Br/I)3 NCs/TCTA/MoO3/Au. This design avoids ion exchange between different perovskites NCs, and realizes white light emission by simple fabrication. As a result, we achieved the white light coordinates of (0.34, 0.34) and a correlated color temperature of 5153 K.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ECS Journal of Solid State Science and Technology
·
2020
·Vol. 9
·期 12
·126001
·
IF 2.142
Dongxin Shi,Xiaoling Xie,Haiqi Pu,Xi Zhang,Qiang Zhou,Zhengliang Wang,Yanqing Ye,Minghong Chen
A novel red-emitting Rb2KGaF6:Mn4+ phosphor with octahedral particulate morphology was presented. The XRD Rietveld refinement results indicate that the phosphor crystallized into the cubic phase of Fm\overline{3}m space group with double perovskite structure. The photo-luminescence spectrum exhibits intense red emission lines with zero-phonon line (ZPL) and v6 peak locating at 620 and 628 nm respectively. The optical parameters of low color temperature (Tc = 3824 K) and high color rendering index (Ra = 90.2 ) from white LED imply its potential application in solid-state lighting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2018
·Vol. 47
·期 46
·16696-16703
·
IF 4.099
Lifei Xu,Yan Xu,Xianliang Li,Zhuopeng Wang,Ting Sun,Xia Zhang
The rational design strategy to construct lanthanide ion functionalized metal organic frameworks (MOFs) has attracted tremendous attention as they are promising candidates for developing novel luminescence materials and optical sensors owing to their intense, long-lived and tunable luminescence performances. In this work, a series of Eu3+/Tb3+ singly doped or codoped bismuth-based MOFs were prepared under in situ facile solvothermal conditions using BiOBr nanoplates as bismuth resources. A red-green-blue-based trichromatic white-light emission can be finely achieved by modulating the doping ratio of Eu3+/Tb3+ in the blue-emitting Bi-MOF host material and such photoluminescence tuning can also be realized by controlling the excitation wavelength. In addition, the Eu3+/Tb3+ singly incorporated Bi-MOF can serve as a multifunctional fluorescent probe for sensing Fe3+ and Cr2O72− ions in aqueous solution, as well as small organic pollutants of acetone molecules, and their sensing mechanisms have also been analyzed. These lanthanide ion functionalized Bi-MOF materials exhibit great potential in exploring white-light emitting devices and construction of supersensitive multifunctional sensors.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子