Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 26
·9030-9036
·
IF 6.4
Jinyi Wang,Xudong Wang,Chenjie Zhang,Xinyu Zhang,Tianliang Zhou,Rong-Jun Xie
Near-infrared (NIR) phosphors play a key role in phosphor-converted NIR emitters, but to find broadband phosphors still remains a great challenge due to the lack of strategies for screening appropriate hosts. Herein, we report a broadband Sr6Sc2Al4O15:Cr3+ NIR phosphor by choosing a host that has crystallographic sites accommodated for both Ce3+ and Cr3+ simultaneously. The emission spectrum of Sr6Sc2Al4O15:Cr3+ covers the region of 600–1500 nm, having a maximum at 860 nm and a full width at half-maximum (FWHM) of 241 nm. A NIR pc-LED was fabricated by combining the Sr6Sc2Al4O15:Cr3+ phosphor with a blue LED, which can produce a NIR output power of 0.16 mW driven at 750 mA. The fabricated NIR emitter demonstrates a good suitability in night vision and non-destructive detection.
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
Nano Research
·
2020
·Vol. 14
·期 3
·628-634
·
IF 8.183
Zhang Xinsu,Chen Yujuan,Lian Linyuan,Zhang Zizhen,Liu Yixuan,Song Li,Geng Chong,Zhang Jianbing,Xu Shu
Infrared lead chalcogenide quantum dots (QDs) suffer fast degradation due to the easy oxidation of surface chalcogen atoms. Here, we report a trioctylphosphine-mediated surface passivation method to improve the air stability of PbS QDs. Surface mechanism study reveals an in situ surface reaction, which leads to site-selective passivation of surface S atoms with lead mono-carboxylate. The surface capping motif sufficiently protects PbS QDs from oxygen and improves their stability as well as quantum efficiency regardless of the QD size and original ligands on surface cations. The modified PbS QDs display no obvious fluorescence quenching and surface oxidization after 30 days of air exposure. The robust surface capping also provides high compatibility of PbS QDs with polymers for optoelectronic device fabrication. The near-infrared LEDs based on the modified PbS QDs display a slight degradation of only 1.47% from the maximum intensity after continuous operation in air for 250 hours (lifetime > 10,000 h) at 0.5 W/cm 2 power density, indicating the surface passivation route is promising strategy for promoting practical optoelectronic application of PbS QDs.
研究领域:
材料科学
·
光电技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Baochen Wang,Cheng Yan,Kaiwei Shen,Weiwei Lin,Yan-gai Liu,Ruiyu Mi,Chao Zeng
Cr 3+ doped phosphor shows great potential for near-infrared (NIR) light-emitting diodes (LED), but it suffers from low quantum efficiency and poor thermal stability. Herein, a novel Cr 3+ doped broadband NIR garnet Ca 3 Sc 2 Ge 3 O 12 phosphor was developed. The multisite structure of the emission band is investigated by site-selective spectroscopy and is attributed to the octahedral Cr 3+ perturbed by defects. Moreover, we propose different strategies to enhance the luminescence of the phosphor, including enhancement of crystallinity and elimination of defects. Compared with the initial sample, the emission intensity of the optimized phosphor is improved for 8.6 times. The optimal Ca 3 Sc 2 Ge 3 O 12 : 0.06Cr 3+ phosphor exhibits excellent thermal stability. At 423 K, the integral emission intensity of the optimal sample remains 94.7% of that at room temperature. Finally, high-performance NIR LED was fabricated using a blue LED and the title phosphor. The packaged LED lamp has high radiance (109.3 mW@300 mA) and photoelectric efficiency (15.96%@40 mA). Our study not only provides a boulevard for enhancing the luminescence of Cr doped NIR phosphor, but also gives a new perspective for understanding the multisite luminescence of Cr 3+ in garnet host.
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
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Zecheng Cao,Xiaojiao Kang,Wei Lü,Weiliang Guan
In this study, we present a novel synthesis system for AgInS 2 /ZnS (AIS/ZnS) core/shell quantum dots (QDs) terminated with carboxymethyl chitosan (CMC) as a ligand, which has not been previously documented. By varying the Ag/In ratio, we achieved emission wavelengths ranging from 590 to 697 nm, with the maximum photoluminescence quantum yield (PLQY) of 33.1 %. The synthesized AIS/ZnS QDs powder was mixed with YAG phosphor and combined with a blue gallium nitride (GaN) chip to produce a warm white light-emitting diode (WLED), resulting in the color rendering index (CRI) increase from 74 to 82 and the correlated color temperature (CCT) decrease from 6486 K to 3873 K. Additionally, the AIS/ZnS QDs powder can be directly utilized with a blue GaN chip to create a near-infrared light-emitting diode (NIR-LED) capable of night vision. By adjusting the concentration of CMC in the AIS/ZnS QDs solution, the material can be directly used for writing and screen printing, or dried to obtain a highly transparent and luminescent flexible composite film. This research demonstrates the significant potential of CMC-ligated AIS/ZnS core/shell QDs in display technologies and flexible device applications.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Zixuan Wu,Xinxin Han,Yayun Zhou,Ke Xing,Sheng Cao,Li Chen,Ruosheng Zeng,Jialong Zhao,Bingsuo Zou
High performance broadband Near-infrared (NIR) phosphors with high efficiency and excellent thermal stability are highly demanded for constructing the next generation of NIR radiation sources. Herein, a broadband NIR emitting fluoride phosphor K 2 NaInF 6 :Cr 3+ peaking at 774 nm with a Full width at half maximum (FWHM) of 116 nm (1906 cm −1 ) was demonstrated. A high Internal quantum efficiency (IQE) value of 70.2% can be obtained in the as-synthesized K 2 NaInF 6 :Cr 3+ phosphor. Additionally, benefiting from the relatively weak electron phonon coupling effect, the phosphor also exhibits excellent anti-thermal quenching behavior with the emission intensity at 150 °C retaining 78.3% of that at room temperature. A high power NIR pc-LED with NIR radiant flux of 492.85 mW@1050 mA is obtained by combing the as-synthesized K 2 NaInF 6 :Cr 3+ phosphor and a blue LED chip. Utilizing this high power NIR pc-LED as NIR radiation source, high-resolution human hand veins imaging is realized with the assistance of a NIR camera, which indicates that K 2 NaInF 6 :Cr 3+ phosphor has high potential in biological applications.
研究领域:
材料科学
·
光电技术
·
生物医学工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Xiaobin Wang,Changyu Li,Zhuoyi Li,Xu Ma,Danke Chen,Xinyi Wan,Zheng Deng,Renren Deng,Xinsheng Peng
The existing white light-emitting diodes (WLEDs) are mostly fabricated with downshifting phosphors and ultraviolet (UV) or blue light LED chips. To achieve unconventional upconversion white-light-emitting phosphors, a novel strategy by encapsulating upconversion nanoparticles and organic dyes into metal–organic frameworks (MOFs) at room temperature is put forward. Herein, lanthanide-doped upconversion nanoparticles (NaYF 4 :Yb,Tm@NaYF 4 core–shell UCNPs), dye 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) and dye Coumarin 6 (C6) with blue, red and green light emission, respectively, are encapsulated together into ZIF-8 through a facile one-pot solid-confinement conversion process. Owing to their appropriate spectral overlaps and efficient energy transfer processes between two pairs of UCNPs/DCM and UCNPs/C6 within ZIF-8, the optimized UCNP/DCM/C6@ZIF-8 thin film exhibits high-quality white-light emission upon a commercial 980 nm LED chip with ideal CIE coordinates of (0.33, 0.33), high color rendering index (CRI) value of 93 and moderate correlated color temperature (CCT) value of 5567 K. This strategy paves the way for other upconversion phosphorous nanoparticles and fluorescent molecules for WLEDs applications excited by near infrared light.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xin Tong,Hongquan Yu,Xiangping Li,Sai Xu,Baojiu Chen
Owing to their environmental friendliness, structural tunability, and ability to emit self-trapped excitons, lead-free halide double perovskites (DPs) have demonstrated significant potential for applications in light-emitting diodes (LEDs) and photodetectors. However, their chemical and thermal stability is generally insufficient. These limitations hinder their practical application in LEDs, as these devices typically generate considerable heat under high operating currents and prolonged usage, particularly in the case of infrared LEDs. In this work, Er 3+ -doped double perovskites (Cs 2 NaYCl 6 and the Cs 2 NaYCl 6 @0.6 KBr composite) were synthesized via a hydrothermal method. The emission intensity of Cs 2 NaYCl 6 :2 % Er 3+ @0.6 KBr is five times greater than that of Cs 2 NaYCl 6 :2 % Er 3+ within the wavelength range of 1400–1600 nm. In the Cs 2 NaYCl 6 :Er 3+ @0.6 KBr composite, the surface defects of Cs 2 NaYCl 6 :Er 3+ were modified by the introduction of KBr, leading to an increase in the external quantum efficiency (EQE) of Cs 2 NaYCl 6 :Er 3+ from 9.5 % to 30.0 %. Under a 150 mA working current, the operating temperatures of the near-infrared (NIR) LED devices based on the Cs 2 NaYCl 6 :2 %Er 3+ and Cs 2 NaYCl 6 :2 %Er 3+ @0.6 KBr composite are 53.2 and 47.4 °C, respectively. After working for 2 h, the temperatures of the NIR LEDs based on Cs 2 NaYCl 6 :2 %Er 3+ and Cs 2 NaYCl 6 :2 %Er 3+ @0.6 KBr were 60.3 °C and 46.0 °C, respectively, under a 100 mA operating current.
研究领域:
材料科学
·
光学工程
·
固态照明技术
·
稀土发光材料
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2023
·
IF 4.5
Fuhua Gao,Wasim Ullah Khan,Zhiyuan Cheng,Waheed Ullah Khan,Iqtidar Ahmad,Zhiqi Ye,Shenghong Yang,Yueli Zhang
Broadband near-infrared (NIR)-emitting materials have critical applications in biology, medical detection, and NIR night-vision. However, developing NIR phosphors with promising optical properties and excellent thermal stability is a great challenge for research. In this work, a novel NIR phosphor Cr 3+ and Yb 3+ doped CaSc 2 O 4 (CSO) is an evolving NIR emitting phosphor with decent optical properties , boosted emission intensity, and thermal stability that makes it a promising candidate with potential applications in NIR-LED and infrared night-vision. The implications of the fundamental electronic structure of CSO, including valence-band (VB) and conduction-band (CB) orbital character, are investigated. Under blue light excitation, CSO:Cr 3+ is settled with pure broadband NIR emissions (max = 920 nm, FWHM (full width at half maximum) = ∼310 nm) and good thermal stability . The occupation of two selectable lattice sites of Cr 3+ in CSO is discussed in detail. Furthermore, emission enhancements of samples are done by Cr 3+ and Yb 3+ codoping, effectively broadening FWHM to 351 nm and reducing thermal quenching. The energy transfer (ET) routes in CSO:Cr 3+ ,Yb 3+ are investigated based on PL lifetime and comprehensive kinetic ET model, revealing that the PL enhancements by Cr 3+ and Yb 3+ codoping mainly originate from the ET from Cr 3+ to Yb 3+ emitters with more efficient and thermally stable. Finally, an InGaN-LED device encapsulated using CSO:0.01Cr 3+ and CSO:0.01Cr 3+ ,0.01 Yb 3+ phosphor was fabricated. The fabricated NIR pc-LEDs are excellent candidates for NIR light sources in biological imaging and NIR night vision.
研究领域:
光学材料
·
生物医学成像
·
光电子学
·
无机发光材料
·
红外技术
·
固态照明
·
纳米生物技术
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 19
·6569-6577
·
IF 4
Shihao Wu,Heng Liang,Yan Li,Wanfang Zou,Zhijian Liao,Wei Wang,Xinyu Ye
The Cr3+-doped near-infrared (NIR) phosphors have been extensively investigated owing to their promising applications in biomedicine, food safety detection, and night vision surveillance. However, achieving broadband (FWHM > 160 nm) NIR emission is still challenging. In this paper, novel Y2Mg2Ga2−xSi2O12:xCr3+ (YMGS:xCr3+, x = 0.005–0.08) phosphors were prepared by a high-temperature solid-state reaction. The crystal structure, photoluminescence properties of the phosphor, and the device performance of a pc-LED were researched in detail. When excited at 440 nm, the YMGS:0.04Cr3+ phosphor exhibited broadband emission in the range of 650–1000 nm, peaking at 790 nm with a full width at half-maximum (FWHM) of up to 180 nm. The wide FWHM of YMGS:Cr3+ is conducive to its extensive application in NIR spectroscopic technology. In addition, the YMGS:0.04Cr3+ phosphor could maintain 70% of the initial emission intensity at 373 K. By combining the commercial blue chip with the YMGS:0.04Cr3+ phosphor, the resulting NIR pc-LED demonstrated a near-infrared output power of 14 mW with a photoelectric conversion efficiency of 5% at a drive current of 100 mA. This work provides a broadband emission NIR phosphor option for NIR pc-LED devices.
研究领域:
材料科学
·
光学工程
·
生物医学工程
·
光电子学
·
固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Xiao-Na Shen,Yu-Guo Yang,Wei Zhao,Xu-Ping Wang,Yuan-Yuan Zhang,Bing Liu,Hua-Jian Yu,Cheng-Cheng Qiu,Xian-Shun Lv,Rui Zhang,Lei Wei,Hua-Di Zhang
Phosphor-converted near-infrared light-emitting diodes (pc-NIR-LEDs) exhibit unique advantages over traditional NIR light sources, shifting the research focus toward high-performance NIR phosphors. The transition metal Cr 3+ ion serves as an ideal NIR activator, displaying highly sensitive emission characteristics that are strongly influenced by the primary crystal field environment. However, reports on Cr 3+ doping in SrLaGaO 4 (SLG) with a disordered structure as the host material remain limited. This study focuses on the synthesis of SrLaGa 1-x O 4 :x%Cr 3+ phosphors, where x ranges from 0.2 to 1.2. The optimized SLG:Cr 3+ phosphor demonstrates ultra-wideband NIR emission spanning from 650 to 1250 nm under excitation at 429 nm. Notably, the material exhibits superior thermal stability (ΔE = 0.35 eV, E G = 5.17 eV), retaining 66.55 % emission intensity at 423 K. Detailed optical analysis reveals that the emission from Cr 3+ -Cr 3+ ion pairs during the ( 4 A 2 , 4 T 2 → 4 A 2 , 4 A 2 ) transitions results in non-uniform broadening of the optical transition, which is one of the key factors contributing to its superior NIR performance. The output power of the pc-NIR-LED based on the SLG 0.99 :1.0 % Cr 3+ and 430 nm chip reached 0.418 W@150 mA. The results suggest that the novel SLG:Cr 3+ phosphor holds great prospects for advancing NIR lighting technology.
研究领域:
材料科学
·
光学物理
·
固态照明
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Science China-Materials
·
2025
·Vol. 68
·期 8
·2725-2734
·
IF 7.4
Wang Machao,Tang Yangmin,Pu Guiqiang,Kang Chengbin,Wang Zhiqiang,Liu Lijia,Li Jing,Zhou Zhenzhen,Chen Wei,Wang Dong,Wang Jiacheng
Self-trapped excitons are prevalent in metal halide perovskites (MHPs) characterized by soft lattices and strong exciton-phonon coupling, emitting photons with broadband emission and large Stokes shifts, rendering them particularly well-suited for applications in light-emitting diodes. But their photoluminescence quantum yields (PLQY) are limited by both high exciton binding energy and halogen-vacancy-associated non-radiative recombination. Here, we show that PLQY could be enhanced by a factor of 5.6 from 16% to 89% through doping trace Ag into Cs 2 NaBiCl 6 double perovskites, superior to those of previous Cs 2 NaBiCl 6 -based emitters. Experimental and theoretical studies reveal that trace Ag-initiated covalent interactions could reduce the exciton binding energy by 0.12 eV due to local symmetry breaking, thus improving the photoexcitation process. Also, this covalent interaction could passivate Cl vacancy defects, suppressing non-radiative recombination. Therefore, Cs 2 NaBiCl 6 : 0.7% Ag + could accumulate active self-trapped excitons to obtain high PLQY. Assembly of near-infrared light-emitting diodes using Cs 2 NaBiCl 6 : 0.7% Ag + illustrates their valuable applications in nondestructive spectral analysis and night vision illumination. This work shows an effective strategy of improving photoemission of MHPs with high PLQY for advanced optoelectronic applications.
研究领域:
材料科学
·
光电子学
·
光物理
·
半导体材料
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Shuo Wang,Shuhan Zhang,Xin Li,Dan Huang,William W. Yu,Liang Wang
Near-infrared (NIR) emission underpins biomedical imaging, night vision, and optical communication. Yb 3+ -doped CsPbCl 3 have demonstrated ultrahigh photoluminescence quantum yields via quantum cutting, primarily enabled by a singular defect-assisted energy transfer pathway arising from the substitution of Pb 2+ by Yb 3+ . However, whether additional pathways exist to facilitate visible (VIS)-to-NIR conversion, thereby further enhancing the performance of NIR-emissive devices, remains an open and compelling question. Here, strategic engineering of localized bound excitons (BEs) is proposed in the thermally evaporated CsPbCl 3 :Yb system. Assisted BEs significantly promote energy transfer from CsPbCl 3 matrix to Yb dopants, unveiling a previously unknown excitonic energy transfer channel. Atomic-scale characterization combined with first-principles calculations uncovers a BE-driven excitonic transfer mechanism, specifically implicating Cs-vacancy-induced defects in mediating exciton behavior. These insights lead to the fabrication of high-performance NIR-LEDs with an 8.9% external quantum efficiency and 410 mW·Sr −1 ·m −2 radiance, marking a breakthrough in thermally evaporated NIR (>950 nm) light-emitting diodes.
研究领域:
光电子学
·
材料科学
·
钙钛矿发光二极管
·
能量转移物理
·
纳米材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）