CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Junze Tong,Long Li,Haiqing Su,Feng Hong,Edwin Yue Bun Pun,Hai Lin
Red-emitting Mn 4+ -doped fluoride phosphors are promising fluorescent material for use in high-performance warm white light emitting diodes (WLEDs). However, low stability and non-green synthesis method limit the development and commercialization of such phosphor. Herein, a series of novel (Li/Na/Cs) 0.4 Ba 0.8 SiF 6 :Mn 4+ phosphors with optimized fluorescence properties induced by alkaline metal ions replacement are successfully synthesized via a green and eco-friendly approach. Under the irradiation of 460 nm blue light, Cs 0.4 Ba 0.8 SiF 6 :Mn 4+ red phosphor with narrow band emission peak has the best optical performance. The optimal doping concentration of Mn 4+ in Cs 0.4 Ba 0.8 SiF 6 host and the reason for concentration quenching are systematically analyzed. Furthermore, the moisture resistance and thermal stability of this phosphor are discussed. After being soaked in deionized water for 90 min, the PL intensity of Cs 0.4 Ba 0.8 SiF 6 :Mn 4+ phosphor can maintain at 40% of that in air, which is 4 times higher than commercial K 2 SiF 6 :Mn 4+ . At the operating temperature of LED (423 K), Cs 0.4 Ba 0.8 SiF 6 :Mn 4+ red phosphor can exhibit stable light output intensity and color. A warm WLED with low correlated color temperature of 4336 K, high color rendering index of 88.4 and high lumen efficiency of 105.96 lm/W is fabricated via using Cs 0.4 Ba 0.8 SiF 6 :Mn 4+ phosphor as a component of red-light, and the warm WLED can maintain stable output even at high driving currents. Overall, the alkali metal ion replacement and green synthesis strategies have opened up a new perspective for the synthesis of efficient Mn 4+ -doped fluoride phosphors, which has dual benefits for optimizing the performance of WLED and environmental protection.
研究领域:
材料科学
·
光学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2023
·
IF 9
Xiu-Xian Guo,Jun-Hua Wei,Jian-Bin Luo,Zi-Lin He,Zhi-Zhong Zhang,Jing-Hua Chen,Dai-Bin Kuang
Single-source white-light emitters are highlighted with stable color and excellent color rendering ability, which can largely simplify the white-light-emitting-diode (WLED) structure. All-inorganic and lead-free double perovskites have attracted extensive research interest and provide versatile doping sites to accommodate the extrinsic multi-valent ions. Herein, the synthesis and tunable emission of Sb 3+ –Ln 3+ -codoped Cs 2 NaYCl 6 single crystals (SCs) is reported. Particularly, bright white-light emission with a high photoluminescence quantum yield of 80.5% is yielded in 0.5%Sb 3+ –2%Tb 3+ –2%Sm 3+ -codoped Cs 2 NaYCl 6 SCs. Steady-state photoluminescence (PL) and time-resolved PL spectra are employed to reveal the energy transfer from Sb 3+ -induced self-trapped excitons to Ln 3+ ions. Temperature-dependent PL spectra further demonstrate that the fluorescence intensity ratio of band 657 to band 590 nm is highly dependent on the temperature, and the relative sensitivity reaches a maximum of up to 1.59% K −1 at 260 K. Moreover, the WLED based on 0.5%Sb 3+ -2%Tb 3+ -2%Sm 3+ -codoped Cs 2 NaYCl 6 SCs delivers a higher average color rendering index of 87 than 0.5%Sb 3+ -0.8%Tb 3+ -2.5%Ho 3+ -codoped Cs 2 NaYCl 6 (74.6). The outstanding white-light-emission performance together with the high temperature dependence of the fluorescence spectra confers Sb 3+ –Ln 3+ -codoped Cs 2 NaYCl 6 with huge application potential in solid-state lighting and ratiometric optical thermometry.
研究领域:
材料科学
·
光学
·
固态照明
·
温度传感
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Jianyan Ding,Dewu Wu,Shanshan Ye,Quansheng Wu
The advancement of narrow-band cyan-emitting phosphors activated by near-ultraviolet LED chips is crucial for creating high-efficiency, health-promoting WLED lighting. Guided by a single and symmetrical crystallographic site, a near-ultraviolet excitation, near-narrow-band, and thermally stable cyan light emission was achieved from Bi 3+ -activated garnet-structured Ca 3 Xn 2 Ge 3 O 12 :Bi 3+ (Xn = Sc, Y, Lu). When incorporated into WLEDs, the color rendering index (CRI) of devices containing Ca 3 Sc 2 Ge 3 O 12 :Bi 3+ cyan phosphor reaches 92.8, indicating potential value for healthy lighting applications. Furthermore, by integrating spectral and crystallographic data with empirical formula calculations, a comprehensive analysis of the luminescence behavior among the three Ca 3 Xn 2 Ge 3 O 12 :Bi 3+ (Xn = Sc, Y, Lu) phosphors were performed. This analysis was designed to elucidate the similarities and differences in their luminescence properties, as well as to uncover the underlying mechanisms responsible for the near-narrow-band emission of Bi 3+ . The results indicate that under the combined influence of factors volume polarization, fractional covalency, and charge of the anions, Ca 3 Xn 2 Ge 3 O 12 :Bi 3+ (Xn = Sc, Y, Lu) exhibits the same strongest excitation peak. However, due to variations in Stokes shift and bandgap, the three phosphors exhibit distinct emission peaks and thermal quenching properties. This study aims to establish fundamental principles for the development of Bi³ ⁺-activated narrow-band emission phosphors.
研究领域:
材料科学
·
光学材料
·
固态照明
·
无机化学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2025
·
IF 3.4
Chengyu Ni,Kaiting Wu,Chunxuan Chen,Xiaozhou Zheng,Man Xu,Wubin Dai
The design of a stably efficient and color-tunable photoluminescence (PL) phosphor, depending on the clear relationship between structure/composition and PL properties, remains quite a challenge. Herein, in pursuit of phosphor for white LED (wLED) lighting, chemical modification of the host (K3YSi2O7, KYS) and regulation of the energy transfer of dopants Bi3+/Eu3+ in multiple lattice sites (K/Y) are in detail investigated and achieved via a facile solid-phase reaction under air condition. Based on both experimentally and theoretically comprehensive analysis of structure (i.e., XRD/Rietveld refinement, density functional theory (DFT) calculations) and steady/transient-state spectroscopy (i.e., PL/PL excitation, decay lifetime), the adjustable and broad PL in the blue/cyan region of Bi3+ is originated from both the crystallographic sites of K1/Y2, while Eu3+ ions are more inclined to enter the Y2/Y1 sites and emit the characteristic high-purity red PL. Systematic PL tuning from blue/cyan to red is thus realized via efficient ET from Bi to Eu, and the corresponding PL and ET mechanisms are discussed and proposed. Intriguingly, significant enhancements of the PL intensity, quantum yield (QY), and thermal stability of the KYS: Bi/Eu are achieved via chemical composition modulation by artificially adding excessive K+ ions to the host to enhance the phase purity/crystallinity. By adopting the phosphor as a “warm” white color convertor, a wLED with high efficiency and color rendering index (CRI, 90.5) and low corrected color temperature (CCT, 4126 K) is constructed via a remote “capping” packaging strategy. Further, in view of the different thermal responses of the multisite occupancy of Bi3+, energy-level thermal coupling of Eu3+, and dual centers of Bi/Eu in KYS, a multimode and self-referenced thermometer is also designed based on the fluorescence intensity ratio (FIR) technology with high relative sensitivity.
研究领域:
材料科学
·
光学材料
·
固态照明
·
发光材料
·
温度传感技术
·
无机化学
✓ 已验证
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2024
·
IF 3.2
Pengju Xia,Yifeng Lei,Wanyuan Li,Kaiting Wu,Chengyu Ni,Man Xu,Wubin Dai
With the growing public awareness of protecting vision and prevention of hazardous effects, there is much-needed research on a “healthy” full visible spectrum under near-ultraviolet (nUV) excitation in phosphor-converted white light-emitting diodes (pc-wLEDs) to fill the “cyan gap” and avoid employing a blue LED chip. Herein, a novel series of borosilicates Ba2CaB2Si4O14 (BCBS): Ce3+/Tb3+/Sm3+/Sr2+/Na+ phosphors, presenting color-tunable photoluminescence (PL), high quantum yield (QY), and thermal stability, were designed and synthesized via a facile solid-phase reaction. The Rietveld analyses, density functional theory (DFT) simulations, and theoretical calculations of bond energy together imply the site occupations of Ce/Tb/Sm on Ba2+/Ca2+ sites with a preferred location on Ca2+ over the Ba2+ site. The broad/bright cyan-PL from BCBS: Ce under nUV excitation is associated with the allowed f–d transitions of Ce3+ and dual-site occupancies. The forbidden f–f transitions of both the green-PL of Tb and the red-PL of Sm were insensitive to the site environment and helpful to PL color regulation. The cascading Ce → Tb → Sm energy transfer is confirmed, where Tb is regarded as an energy transfer (ET) bridge to avoid the metal–metal charge transfer (MMCT) effect. The introduction of Na+ as both flux and charge compensator is for the sake of decreasing defects from heterovalent substitutions and regulating morphology. Further incorporation of Sr2+ is to modulate the lattice environments of dopants for controlling the shift of PL. Finally, as a proof-of-concept implement, a pc-wLED assembled by BCBS: Ce/Tb/Sm/Sr/Na and an nUV LED chip via a remote “capping” packaging strategy show attractive performance.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2023
·
IF 3.9
Yu Zhang,Guangning Hou,Yong Wu,Maosheng Chen,Yannan Dai,Shaohua Liu,Qingbiao Zhao,Hechun Lin,Junfeng Fang,Chengbin Jing,Junhao Chu
Oleylamine/oleic acid (OAm/OA) as the commonly used ligand is indispensable in the synthesis of perovskite nanocrystals (PNCs). Unfortunately, poor colloidal stability and unsatisfactory photoluminescence quantum yield (PLQY) are observed, resulting from a highly dynamic binding nature between ligands. Herein, we adopt a facile hybrid ligand (DDAB/ZnBr2) passivation strategy to reconstruct the surface chemistry of CsPbBr3 NCs. The hybrid ligand can detach the native surface ligand, in which the acid–base reactions between ligands are suppressed effectively. Also, they can substitute the loose capping ligand, anchor to the surface firmly, and supply sufficient halogens to passivate the surface trap, realizing an exceptional PLQY of 95% and an enhanced tolerance toward ambient storage, UV irradiation, anti-solvents, and thermal treatment. Besides, the as-fabricated white light-emitting diode (WLED) utilizing the PNCs as the green-emitting phosphor has a luminous efficiency around 73 lm/W; the color gamut covers 125% of the NTSC standard.
研究领域:
材料科学
·
纳米技术
·
光电技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2021
·Vol. 13
·期 21
·9634-9640
·
IF 7.79
Shuhua Chen,Qixuan Zhong,Jun Liu,Wenhao Guan,Pengli Li,Israr Mahmood,Muhan Cao,Qiao Zhang
All-inorganic lead halide perovskite nanocrystals (NCs) have been promising candidates in various optoelectrical fields. It is still challenging to further enhance their optical properties and stability to meet the requirements of practical applications. Herein, we develop a passivation strategy towards CsPbBr3 NCs by using inorganic phosphate and bromide anions. Phosphate can coordinate with lead ions on CsPbBr3 NCs as capping ligands; meanwhile, excess bromide can strengthen the repair of surface trapping sites. The treated NCs exhibit near-unity quantum yield and boosted radiative recombination. In addition, obvious enhancement has been realized in their durability against polar solvents. A white light emitting diode (WLED) has been fabricated by employing the passivated NCs as a green light source, which possesses high luminous efficiency and operational stability.
研究领域:
材料科学
·
光电技术
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Ruifeng Liu,Yunluo Wang,Haoming Qin,Xuchang He,Shihao Ge,Jianghua Wu,Tianrui Zhou,Tingting Ye,Zesen Gao,Futing Sun,Jingshan Hou,Yihui He,Lianjun Wang,Haijie Chen,Wan Jiang
Lead-free halides, with the advantages of non-toxicity and high stability, have broad application prospects. Here, we studied the synthesis and luminescent properties of the Sb-doped Rb 2 ZnCl 4 and explored their utilizations for white light-emitting diode (WLED) and X-ray detection. The as-synthesized Rb 2- x Zn 1- x Sb x Cl 4 single crystals exhibit bright red emission centered at 740 nm with a large full width at half maximum (FWHM) of 220 nm, and the maximum photoluminescence quantum yield (PLQY) is determined to be 59.7 % for the sample with x = 0.01. The assembled WLED achieves a high color rendering index (CRI) of 93.6 and a low correlated color temperature (CCT) of 3755 K. Under continuous X-ray irradiation for 600 s at a dose rate of 26.5 Gy min −1 , the irradiation luminescence intensity of Rb 1.99 Zn 0.99 Sb 0.01 Cl 4 did not decrease, indicating that the single crystal has a high tolerance to X-ray irradiation. Our work demonstrates that Zn halides are also a promising lead-free family for multiple optoelectronic applications.
研究领域:
材料科学
·
光电子学
·
光子学
·
辐射检测
✓ 已验证
产品关联
DOI
高影响因子
Chemical Science
·
2024
·Vol. 15
·期 8
·2954-2962
·
IF 7.6
Chuying Wang,Wen Meng,Guigen Luo,Guangyong Xu,Min Peng,Bin Xu,Shuming Nie,Zhengtao Deng
Materials with two or more fluorescence features under different excitation sources have great potential in optical applications, but luminous materials with three emission characteristics have been largely undeveloped. Here, we report a novel zero-dimensional (0D) organic–inorganic hybrid ((C2H5)4N)2ZrCl6 perovskite with multiple emissions. The zirconium-based perovskite exhibits a red emission around 620 nm, a green emission at 527 nm, and a blue emission around 500 nm. The red and green emissions come from self-trapped excitons (STEs) and the d–d transitions of Zr(IV), respectively, which are caused by distortion of the [ZrCl6]2− octahedra. The blue emission is caused by thermally activated delayed fluorescence (TADF), which is similar to that of Cs2ZrCl6. The absolute photoluminescence quantum yield (PLQY) of the red and blue double emission is up to 83% and the PLQY of the green emission is 27%. With different combinations of ((C2H5)4N)2ZrCl6 samples, we achieve a variety of applications, including a two-color luminescent anti-counterfeiting device, a white light-emitting diode (WLED) with a color rendering index (CRI) of 95 and information encryption with different excitations. We also synthesize other hybrid zirconium perovskites with tri-luminescence through a similar method. Our work provides a potential set of excitation-dependent luminescent materials and is expected to expand the basic research and practical applications of multi-luminescence materials.
研究领域:
材料科学
·
光学
·
光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Mengran Ouyang,Huimin Du,Jiahao Wu,Shanshan Hu,Jun Yang
KSrGd(PO 4 ) 2 :Ln 3+ (Ln = Ce, Sm, Eu, Tb, Dy, Dy/Eu, Yb/Ho, Yb/Er, Yb/Tm) phosphors were synthesized by high temperature solid state method. Doping the KSrGd(PO 4 ) 2 matrix with 5%Dy 3+ ions resulted in white light emission under 345 nm excitation. The calculated color temperature (CCT) of this white light is 5523 K, indicating as positive white light. It was found that the luminous intensity of the obtained KSrGd(PO 4 ) 2 :5%Dy 3+ at 200 °C was 76.80 % of that at room temperature, showing good thermal stability as well as possibility of application in white LED. Under the excitation at 392 nm, the fluorescence quantum yield of KSrGd(PO 4 ) 2 :10%Eu 3+ is 79.92 %. Energy transfer between Dy 3+ and Eu 3+ is observed in KSrGd(PO 4 ) 2 :Dy 3+ /Eu 3+ samples, with identified mechanism as the quadrupole-quadrupole interaction. Tunable luminescence ranging from white to yellow then to orange-red is achieved by adjusting the doping concentration of Eu 3+ in KSrGd(PO 4 ) 2 :5%Dy 3+ , x%Eu 3+ . Under the excitation of 980 nm near-infrared light, the prepared KSrGd(PO 4 ) 2 :Yb 3+ /Ho 3+ , KSrGd(PO 4 ) 2 :Yb 3+ /Er 3+ and KSrGd(PO 4 ) 2 :Yb 3+ /Tm 3+ samples showed up-conversion emissions of red, yellow and blue, respectively, with two-photon processes. In KSrGd(PO 4 ) 2 matrix, multi-color and multi-security marks were successfully prepared by utilizing up/down conversion luminescence characteristics, which obtained good anti-counterfeiting effect and improved anti-counterfeiting security. Therefore, the obtained KSrGd(PO 4 ) 2 : Ln 3+ phosphors exhibit promising application prospects in the fields of WLED and multiple anti-counterfeiting.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Zhili Xu,Shuanglai Liu,Wenwu You,Mingxing Li,Jiacai Li,Pingping Fan,Xu Zhao,Gencai Pan,Huiping Gao,Yanli Mao
Organic–inorganic hybrid metal halides have attracted considerable attention due to their facile synthesis, low cost, and high thermal and chemical stability. However, developing environmentally benign, readily synthesized, high-performance, and spectrally tunable broadband-emitting materials remains challenging. Herein, this study reports a zero-dimensional perovskite material, TEA2HfCl6:Sb3+, using a room-temperature coprecipitation method. This material exhibits low toxicity and excitation-wavelength-dependent modulation of singlet and triplet emission ratios, enabling broadband emission ranging from warm white to deep red. Notably, TEA2HfCl6:11%Sb3+ achieves a high photoluminescence quantum yield of up to 93.1%. Steady-state and time-resolved spectroscopic analyses reveal that these emissions arise from Sb3+-induced radiative transitions of singlet and triplet self-trapped excitons. Furthermore, leveraging its scalable synthesis process and favorable emission characteristics, the material shows potential for applications in large-area optical anticounterfeiting paper and full-spectrum, eye-friendly white-light-emitting diode (WLED). These findings highlight the dual functionality of TEA2HfCl6:Sb3+ in secure optical encryption and solid-state lighting, providing a promising platform for the development of multifunctional luminescent materials.
研究领域:
材料科学
·
光电子学
·
发光材料
·
固态照明
·
安全与加密
·
无机化学
·
纳米材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2022
·Vol. 52
·期 1
·547-558
·
IF 2.047
Zhou Jian,Ren Sili
The phosphor-converted white light-emitting diode (WLED) has received tremendous attention as a promising alternative to traditional light sources in lighting and displays. Herein, a novel broadband red emitter Ca 2 Sr(PO 4 ) 2 :Mn 2+ was successfully designed and synthesized based on the Sr-alloying and Mn-doping of Ca 3 (PO 4 ) 2 . The phase purity of the materials was verified by x-ray diffraction (XRD) analyses, while a scanning electron microscope (SEM) coupled with an energy-dispersive spectrometer (EDS) was employed to confirm the uniform dopant distribution. XRD Rietveld refinements were further performed to clarify the site occupation of alloying Sr and the Mn dopants. Effective site engineering confined the Mn dopants in a highly symmetric Ca5 site and excluded the immersion of Sr, leading to an extraordinarily long fluorescence lifetime. Density functional theory (DFT) simulations also revealed the good potential of the materials as host matrices for activators such as Mn 2+ . Finally, Ca 2 Sr(PO 4 ) 2 :Mn 2+ was used to fabricate a WLED prototype based on a near-ultraviolet (n-UV) commercial LED chip, which realized a warm white-light emission and high color rendering index (Ra) of 82.9. This WLED was able to survive the long-term stability test while maintaining high luminous efficacy of ~ 60 lm/W within 20 h, showing its great potential in practical applications.
研究领域:
材料科学
·
光电技术
·
照明技术
·
固体物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）