INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Yiying Zhu,Guoxun Sun,Yining Wang,Yixin Sun,Xiaole Xing,Mengmeng Shang
Doping lanthanide ions is an efficient method to modify the optical properties of lead-free double-perovskite halides. However, most lanthanide-doped double perovskites show a low luminescence efficiency and require a high excitation energy. Here, we have successfully prepared a series of Ho3+-doped Cs2NaBiCl6 microcrystals through a simple hydrothermal method and obtained strong characteristic emissions of Ho3+ at 492 and 657 nm under low-energy excitation (449 nm). After codoping Mn2+, apart from the characteristic emissions from Ho3+ under 450 nm wavelength excitation, the orangish-red luminescence consisting of the emission band centered at 591 nm from Mn2+ and a sharp emission peak at 657 nm from Ho3+ is obtained under 355 nm UV light excitation. Photoluminescence (PL) emission and excitation spectra, along with the PL decay curves, confirm the existence of an energy-transfer channel from Cs2NaBiCl6 to Mn2+ and then from Mn2+ to Ho3+. The enhanced absorption efficiency (10.5 → 70.7%) suggests that the codoping of Mn2+ overcomes the low absorption efficiency caused by f–f forbidden transitions of Ho3+. Finally, the diverse luminescent performance within the Cs2NaBiCl6:Ho3+, Mn2+ phosphor is realized by altering the excitation wavelength, thereby enabling its application in warm-white-light-emitting diodes and plant growth in this work.
研究领域:
材料科学
·
光学工程
·
农业科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2022
·Vol. 106
·期 2
·1216-1229
·
IF 4.186
Guangtao Lu,Yichao Wang,Siqi Piao,Jinsu Zhang,Xizhen Zhang,Xufeng Zhou,Yongze Cao,Xiangping Li,Baojiu Chen
The excellent narrow-band emitters, especially the green ones, are regarded as a pivotal research direction for light-emitting diodes (LED) backlights in liquid-crystal displays (LCDs). A nearly single-peak green emission centered at 513 nm with a full width at half maximum of 28 nm is reached in KAl 11 O 17 :0.1Eu 2+ , 0.15Mn 2+ phosphor via nearly 100% energy transfer (ET) efficiency, and the extended X-ray absorption fine structure analysis elucidates its mechanism, which is that Eu 2+ and Mn 2+ are constrained to form Eu 2+ –Mn 2+ pairs with a small distance 3.7 Å caused by the local environment relaxation inducement. Meanwhile, by creating an unhindered energy flow between Eu 2+ , Mn 2+ and K + /O 2− defect levels through ET and multilevel electron trapped and recombination process, the KAO:Eu 2+ , Mn 2+ phosphors perform superb photoluminescence property with a high color purity of 83%, an excellent thermal stability (94%@200°C), and unexceptionable internal and external quantum efficiencies of 91.7% and 66.4%, which all are superior to characteristics of commercial β-SiAlON:Eu 2+ phosphor. Moreover, the white LED fabricated using KAO:Eu 2+ , Mn 2+ to provide green component shows a wide color gamut of 105% National Television System Committee. These results indicate a potential for an application of our material in LCD–LED backlights, and the design of such local relaxation-induced structure provides a significative reference to develop the new narrow-band emitters.
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
Advanced Optical Materials
·
2016
·Vol. 4
·期 5
·798-806
·
IF 5.359
Enhai Song,Zitao Chen,Ming Wu,Sha Ding,Shi Ye,Shifeng Zhou,Qinyuan Zhang
In contrast to well-known multiple and fixed upconversion (UC) emission bands from lanthanide (Ln 3+ ) ions activated luminescent materials, room temperature wavelength-tunable single-band UC emissions are designed and demonstrated in Ln 3+ ions/transition metal Yb 3+ /Mn 2+ codoped fluoride perovskites ABF 3 (A = K + , Rb + , and Cs + ; B = Mg 2+ , Zn 2+ , and Cd 2+ ). Upon 976 nm laser excitation, the perovskites ABF 3 :Yb 3+ , Mn 2+ exhibit intense single band UC emission centered at 550–610 nm depending on the substitution of the A + and / or the B 2+ species in ABF 3 . Crystal structure and luminescent properties analysis show that the UC emission should originate from the transitions of super-exchange coupled Yb 3+ –Mn 2+ pair. The Stokes and UC emission properties, UC luminescence decay behaviors, as well as temperature dependent UC emission properties of ABF 3 :Yb 3+ , Mn 2+ are investigated and discussed in detail. The intense room (or high) temperature UC emission and ultralong UC decay lifetimes (≈25–45 ms) clearly reveal that the perovskites ABF 3 :Yb 3+ , Mn 2+ can be potentially applied in the fields of time-resolved luminescence imaging, lighting, and solid state lasers.
研究领域:
材料科学
·
光学材料
·
无机化学
·
光子学
·
固体物理
✓ 已验证
DOI
高影响因子
Optoelectronics Letters
·
2014
·Vol. 10
·期 5
·343-346
·
IF 0
Song Jun,Sun Liang,Li Jian,Ma Jian,Wang Da-jian
A solid-solution-phase Ba 1.75 Ca 1.25 MgSi 2 O 8 : Eu 2+ , Mn 2+ phosphor in the photosynthetic action spectrum with dual band emissions at 438 nm and 660 nm is fabricated. X-ray diffraction (XRD) confirms the presence of the solid-solution phase. With the supporting information from the diffuse reflection spectrum, a feasible way to obtain higher energy-transfer (ET) efficiency is attained, and the ET efficiency of Eu 2+ -Mn 2+ is enhanced to 76%. The mechanism of this enhancement is owing to variation of the solid solution composition of Ca 3 MgSi 2 O 8 and Ba 3 MgSi 2 O 8 , which contributes to the extension of the critical distance. Temperature-dependent results show an enhancement which is attributed to Ca. These enhancements show great promise for improving eco-lighting devices.
研究领域:
材料科学
·
光电子学
·
无机化学
·
功能材料
·
农业光生物学
✓ 已验证
DOI
Journal of Materials Chemistry C
·
2024
·Vol. 12
·期 18
·6606-6614
·
IF 5.7
Muhammad,Zengce Liu,Junchun Li,Yuanyuan Sheng,Yajing Chang,Ping Chen,Yang Jiang
Lead-free halide perovskites have been developed and have received increasing attention in optoelectronic applications due to their non-toxicity. However, single perovskite phosphors that emit vibrant, tunable-color-temperature white-light are rare. Herein, we used the anti-solvent precipitation method to develop white light-emitting diodes (WLEDs) based on rare-earth-based Sb3+ and Mn2+ co-doped Cs2KYCl6 microcrystals (MCs). The Cs2KYCl6 MCs exhibit tunable dual emissions covering a wideband ascribed to the emission of self-trapped excitons (STEs) from Sb3+ and the 4T1 to 6A1d–d transition of Mn2+. The optimal photoluminescence quantum yield (PLQY) of doped Cs2KYCl6 is 65.78%. The energy transfer process from Sb3+ to Mn2+ is revealed. WLEDs have been successfully constructed by combining the dual emissions from STEs of Sb3+ and the d–d transition of Mn2+. These WLEDs demonstrate impressive optical performance, including CIE chromaticity coordinates (0.3483, 0.4125) and a color rendering index (CRI) of 85.4. This work provides an effective strategy for developing WLEDs based on a single-component material, lead-free perovskites.
研究领域:
材料科学
·
光电学
·
光子学
·
半导体物理
✓ 已验证
DOI
高影响因子
INORGANIC CHEMISTRY
·
2025
·
IF 4.7
Huangyao Chen,Chonghui Qi,Xiang Guo,Jun Zhang,Chaoyong Deng,Ruirui Cui
In lead-free halide double perovskites, doping and alloying are key strategies for optical performance enhancement. However, achieving stable full-spectrum white emission in single-component phosphors remains challenging. Herein, high-quality single-phase white emission is realized in Cs2NaGdCl6 via Sb3+/Tb3+/Mn2+ codoping. Pristine Cs2NaGdCl6 shows a weak sky-blue emission, while Sb3+ doping significantly enhances the self-trapped exciton (STE) intensity. Density functional theory calculations show that Sb3+ doping creates new sensitizing states, boosting the STE emission. Under Sb3+ sensitization, STE energy transfers to Tb3+ and Mn2+. The incorporation of Tb3+ elevates the photoluminescence quantum yield from 0.66% (pristine) to 68.38% (CNGC: Sb3+, Tb3+), while the broadband red emission from Mn2+ plays a critical role in achieving full-spectrum coverage. Tunable white-light emission is achieved via a dopant ratio optimization. Combining the phosphor with a 340 nm commercial light-emitting diode chip produces a white light-emitting diode with a correlated color temperature of 4658 K and a color rendering index of 91.9. Temperature-dependent photoluminescence spectra confirm ratiometric sensing capability, yielding maximum relative sensitivities (Sr) of 1.06%/K (I463 nm/I608 nm) and 1.12%/K (I548 nm/I608 nm) at 298 K. These results demonstrate that this material exhibits multifunctional application potential in the fields of white-light illumination, optical thermometry, and fluorescent anticounterfeiting.
研究领域:
材料科学
·
光学材料
·
固态照明
·
光学传感
·
光子学
·
测温技术
·
防伪技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2024
·
IF 5.7
Yongrun Dong,Wen Li,Tao Huang,Shuaigang Ge,Linghang Kong,Chuang Ning,Zequan Li,Wei Gao,Bingsuo Zou
Recently, lead-free double perovskites have been regarded as a promising alternative to lead halide perovskites due to their wide emission band, and environmental protection and stability properties, and are expected to become a series of rising star materials in the lighting field. However, currently, the growth of most lead-free double perovskites occurs in the strong acid environment, which not only brings high cost and environment risk, but also makes it hard to realize large-scale applications with powder products. Herein, we apply a strategy of in situ synthesis of lead-free double perovskites in a polymer matrix by using a small amount of precursors and relatively friendly DMSO solvent to obtain efficiently luminescent Sb3+/Mn2+ co-doped Cs2KInCl6/PVDF composite films in a large-area. The co-doping of Mn2+/Sb3+ into this inorganic double perovskite matrix makes microcrystals with good crystallinity and size distribution in this polymer. The as prepared co-doping composite film with Mn/Sb feeding ratio 16 : 1 shows the brightest white light emission under 320 nm excitation, with a photoluminescence quantum yield (PLQY) as high as 86.98%. The energy transfer (E-T) from the charge-transfer band to the triplet self-trapped exciton (STE) around Sb3+ and then to the ferromagnetic (FM) coupled Mn2+ pair 3d state was confirmed by the temperature-dependent PL spectra and density functional theory calculations. Finally, a single-compound white light emitting diode with chromatic coordinates of (0.31, 0.33) and fluorescent anti-counterfeiting labels could be fabricated based on this composite film with the best white emission. This work provides a new strategy for the application of lead-free double perovskites in the fields of lighting and anti-counterfeiting.
研究领域:
材料科学
·
光电技术
·
光子学
·
纳米技术
·
照明技术
·
防伪技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）