SUPERLATTICES AND MICROSTRUCTURES
·
2015
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IF 2.097
Renping Cao,Haidong Xu,Dedong Peng,Shenhua Jiang,Zhiyang Luo,Wensheng Li,Xiaoguang Yu
Novel CaWO 4 :Eu 3+ , Mn 2+ red phosphor is synthesized by solid-state reaction method in air. CaWO 4 :Eu 3+ , Mn 2+ phosphor with excitation 268 and 394 nm emits red light with chromaticity coordinates (x = 0.6403, y = 0.3593). The strongest emission bands peaking at ∼615 nm is attributed to 5 D 0 → 7 F 2 of Eu 3+ ion. Strong excitation band peaking at ∼394 nm indicates that the phosphor may be excited by near UV (∼394 nm) chip. Emission intensity of CaWO 4 :Eu 3+ , Mn 2+ phosphor with excitation 268 nm is ∼2 times stronger than that of CaWO 4 :Eu 3+ phosphor owing to energy transfer between Eu 3+ ion and Mn 2+ ion. Energy transfer from WO 4 2 − group and Eu 3+ ion to Mn 2+ ion in CaWO 4 :Eu 3+ , Mn 2+ phosphor may be explained via luminescence properties. Luminous mechanism is analyzed by energy level diagrams of WO 4 2 − group, Mn 2+ and Eu 3+ ion. The paper content is helpful to develop and research other novel phosphors.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Yayu Su,Xiaolei Li,Huiming Ji,Zhihao Zhao,Peng Zhang
The Ca 2+ -Mn 2+ doped LaAlO 3 was prepared by solid state reaction method, and the effects of different doping content of Ca 2+ and Mn 2+ ions on the infrared radiation properties of LaAlO 3 were investigated. The result showed that after doping Ca 2+ and Mn 2+ ions, the infrared radiation properties of LaAlO 3 significantly increased. When 40 mol% Ca 2+ and 50 mol% Mn 2+ ions were doped into LaAlO 3 , the average emissivity in the wavelength range of 1–22 µm was up to 0.90, which was higher than pure LaAlO 3 (0.71). The enhancement of infrared radiation properties of LaAlO 3 was mainly due to the decrease of band gap of LaAlO 3 , the increase of hole carriers absorption of energy, and the increase of lattice vibration absorption after doping Ca 2+ and Mn 2+ ions. Ca 2+ -Mn 2+ doped LaAlO 3 with high infrared radiation properties shows application prospect in the high temperature oxidation environment.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Yao Xiao,Puxian Xiong,Shuai Zhang,Kang Chen,Shuhang Tian,Yongsheng Sun,Peishan Shao,Kexin Qin,Mikhail G. Brik,Shi Ye,Dongdan Chen,Zhongmin Yang
Developing deep-red to near infrared (NIR) materials with multi-mode luminescence is challenging, which has promising utilization in various applications such as stress sensing and dynamic signature anti-counterfeiting. Different to the mainstream non-centrosymmetric mechanoluminescence (ML), a centrosymmetric perovskite compound (MgGeO 3 : Mn 2+ ) ML material is reported. Deep-red to NIR light (600–800 nm) from Mn 2+ ion is confirmed, which is attributed to the strong crystal field within the [MgO 6 ] polyhedron. The stiffness tetrahedral units and large defect accommodating space within the host are favorable for both ML and persistent luminescence (PersL). Mn 2+ ion is the only luminescent center, which is confirmed by spectral characterizations. Based on diffuse reflectance spectra, thermoluminescence analysis and density functional theory calculations, the inherent relationship between PersL, ML and PL is further clarified in detail. Due to the formation of Mn Mg defects, shallow trap significantly become shallower after adding Mn 2+ ions. This study reports a Mn 2+ -doped deep-red to NIR ML phosphor, and further describes the PersL and ML mechanisms via defect engineering regulation. In general, this study may also open up a new approach for the development of efficient NIR ML materials, and show various potential applications such as in anti-counterfeiting and information encryption fields.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Binbin Luo,Yan Guo,Xianli Li,Yonghong Xiao,Xiaochun Huang,Jin Z. Zhang
In this work, Mn2+ has been efficiently and homogeneously doped into two-dimensional (2D) distorted single-layered EA2PbBr4 (EA: ethylammonium) via a reprecipitation method. Both the doped and undoped 2D layered lead halide perovskites (LHPs) were characterized using a combination of X-ray, electron microscopy, and spectroscopy techniques. The Mn2+-doped EA2PbBr4 (EA2PbBr4:Mn2+) shows a 78% photoluminescence (PL) quantum yield (QY) with complete quenching of self-trapped exciton emission because of efficient exciton trapping by defects created by dopants and small activation energy (∼9.8 meV) between the defect states and Mn2+ d states. Compared to the long lifetime (∼1.5 ms) of Mn2+ emission in CsPbCl3, the lifetime in 2D EA2PbBr4 is found to be ∼0.75 ms, resulting from the heavy atom effect. Additionally, the PL QY of Mn2+ emission can be further increased by codoping Zn2+ or Cd2+, which is attributed to a high density of trap states created by codoping, facilitating exciton to Mn2+ energy transfer. These results reveal the key role of trap states in the energy transfer of Mn2+-doped 2D LHPs.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2018
·Vol. 30
·期 7
·075704
·
IF 3.404
Weiwei Chen,Xiaosheng Tang,Zhigang Zang,Yue Shi,Zhaoqi Yang,Juan Du
Doping of Mn2+ into semiconductor nanocrystals has been demonstrated to endow them with novel electronic, optical and magnetic functionalities. In this paper, Mn-doped CsPbX3 (X = Br, Cl) quantum dots (QDs) were synthesized at room temperature via a facile strategy by introducing dimethyl sulfoxide (DMSO)-MnBr2/PbX2 composite as a precursor. The excitonic emission spectra of the as-obtained Mn-doped CsPbX3 QDs can be tuned from 517 nm to 418 nm by adjusting the ratio of PbBr2/PbCl2 precisely, and the luminescence mechanism of the doped QDs is discussed in detail. Moreover, the highest photoluminescence quantum yield of the Mn2+ emission achieves 36.7%, which is comparable with QDs prepared by the conventional hot-injection method. Depending on the ratios of PbPb2/PbCl2, the energy transfer rate from the band-edge to Mn2+ excited state is in the range of 0.006–20.42 × 107 s−1. Furthermore, white light-emitting diodes (LEDs) were successfully fabricated by combining the as-prepared Mn-doped CsPbX3 QDs with commercial UV GaN chips, and the high luminous efficiency of the as-prepared white LEDs was developed to 55.9 lm W−1. This work strongly supports the fact that Mn-doped CsPbX3 QDs are promising materials for application in lighting and displaying fields.
研究领域:
材料科学
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光学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Zhanglin Chen,Wei Cui,Kaiming Zhu,Chunguang Zhang,Chuandong Zuo,Yude Niu,Qi Wang,Xuanyi Yuan,Guanghua Liu
An orange-red emitting Mn 2+ /Si 4+ co-doped AlN phosphor was prepared by an efficient combustion synthesis method. Phase identification and structure characterization were performed using powder X-ray diffraction (XRD) and refined by the Rietveld method. Luminescence and afterglow properties of the AlN-based phosphors such as photoluminescence spectra (PL), CIE values, afterglow decay curves, thermoluminescence glow curves (TL) were systematically studied. Using the Tanabe-Sugano diagram, the Racah parameters B , C , and crystal field splitting parameter Dq of as-prepared phosphor were calculated to be 812 cm −1 , 2168 cm −1 , and 780 cm −1 , respectively. The luminescence intensity and afterglow time were increased, respectively, by about 1.1 and 2.2 times after 3% Si 4+ co-doping. Particular attention was paid to study the mechanism of Si 4+ co-doping on improving luminescence properties using a combination of the above-mentioned method and X-ray photoelectron spectroscope (XPS). Two hypothetical stress cancellation and charge rebalance effects due to Si 4+ co-doping were discussed. Besides, it was found a shallower trap level (0.56 eV, compared to 0.84 eV for those without Si 4+ co-doping) was formed after the co-doping of Si 4+ , which results in enhanced afterglow performance.
研究领域:
材料科学
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光学
✓ 已验证
DOI
高影响因子
RENEWABLE ENERGY
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2024
·
IF 9
Moyu Liao,Ruofei Xiang,Xinwen Zhou,Zhongxu Dai,Li Wang,Hang Qin,Hanning Xiao
Hydrogen generation via methanol steam reforming is a promising method for producing renewable energy. In this work, a series of Mn 2+ -substituted CuAl 2 O 4 spinels were prepared by solution combustion method, and the crystal structure, micromorphology, chemical constitution, reduction behavior, acidity, specific surface area and surface chemical state of the spinels were comprehensively characterized by various equipments. The obtained spinels were washcoated on Cu foams to prepare monolithic catalysts, and the catalytic performance of the catalysts was evaluated in a methanol steam reforming microreactor. Compared with the binary Cu–Al spinel, the Mn 2+ substitution led to a decrease in the particle size, a change in the chemical composition and reduction behavior, a decline in the acidity, an increase in the specific surface area, and an improvement in the surface chemical state. As a result, the release rate of active Cu from the Mn-containing CuAl 2 O 4 spinel was significantly slowed down and the formed nanoparticles were fine, which was believed to be in favor of maintaining a stable catalytic performance longer. Among the prepared catalysts, the monolithic catalyst loaded with Cu 0.4 Mn 0.6 Al 2 O 4 exhibited the highest activity and stability. The findings of this work suggested that introducing Mn 2+ might be a promising way to regulate the Cu releasing property for obtaining a better sustained release catalyst system.
研究领域:
材料科学
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化学工程
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Hanzhi Yao,Yuchi Zhang,Yan Xu
Self-calibrated optical luminescent thermometers were prepared based on Eu 3+ /Mn 2+ co-doped Zn 2 GeO 4 phosphors with controllable morphology via a facile hydrothermal synthesis process. The co-doped concentration of Eu 3+ ions in Zn 2 GeO 4 :Mn 2+ played important roles in the evolution of the morphology and the formation of the dual luminescent emission mode. Depending on different excitation wavelengths ranging from 260 to 360 nm, the dual emission centers located at about 534 nm and 612 nm were ascribed to d - d transition derived from 4 T 1 - 6 A 1 of Mn 2+ ions and f - f transition originated from 5 D 0 - 7 F 2 of Eu 3+ ions, respectively, which gave rise to the excellent self-calibrating temperature sensing functions. The related luminescent and sensing mechanism of the Eu 3+ /Mn 2+ co-doped Zn 2 GeO 4 phosphors are also proposed. The as-obtained Eu 3+ /Mn 2+ co-doped Zn 2 GeO 4 phosphors had a high relative sensitivity ( S r ) of 1.96% ºC −1 between 20 and 80 °C, as well as stable reusability, demonstrating its superiority as a ratiometric luminescent thermometer for temperature sensing applications.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Kuixin Cui,Aili Zhou,Caihong Yu,Shengming Jin
The unavoidable Mn 2+ ions in pulp were considered in the flotation of rhodochrosite, and its effect and relative interaction mechanism on the floatability of calcite served as a typical gangue mineral were investigated through microflotation tests, zeta potential measurements, SEM-EDS detection, solution chemistry calculation, adsorption experiments, FTIR and XPS analyses. There exhibited a good separation performance of rhodochrosite against calcite with OHA collector, but in the presence of Mn 2+ ions, the floatability of calcite was closed to rhodochrosite within a pH of 8.0–10.0, which resulted in the separation difficulty between them. As evidenced, the surface of calcite could be modified by Mn 2+ ions, its isoelectric point shifted positively from 8.91 to 10.06, and Mn 2+ species detected on calcite surfaces were in close proximity to rhodochrosite. It indicated that MnCO 3 precipitates were generated on the surface of calcite. After modified by Mn 2+ , the calcite surface became more active and obviously increased the adsorption amount of OHA. It was verified from zeta potential and XPS analyses that Mn species on the surface of calcite were active sites for OHA adsorption, likely the hydroxamate group of OHA collector chelated with Mn species to form hydrophobic compounds. As a result, Mn 2+ ions in pulp would reduce the flotation selectivity of rhodochrosite from calcite, thus it is necessary to eliminate the disadvantage of Mn 2+ for strengthening flotation.
研究领域:
矿物加工工程
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材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2023
·Vol. 129
·期 11
·794
·
IF 2.7
Wang Xuekai,Cao Yongze,Yan Xianglan,Li Lei,Zhang Xizhen,Zhang Jinsu,Chen Baojiu
17K 2 O–33SnO–50P 2 O 5 –xMnCl 2 glasses with x = 0, 0.6, 1.2, 1.8, 2.4, 3.0 were made using melt quenching at 500 °C low temperature. The structure and photoluminescence properties of these glasses were investigated, and the water resistance was evaluated. The experimental results show that the effectively energy transfer from Sn 2+ to Mn 2+ occurs, and when Mn 2+ doping at 3.0, the energy transfer efficiency reaches 74%. Under 340 nm excitation, the emission wavelength is in the range of 500–800 nm, covering the absorption wavelength of chlorophyll P R and P FR , which indicates that the low temperature glasses can be used for plant cultivation. This glass material was immersed in water for 24 h, and the luminescence intensity decreases 10%. This indicates that the glass material has certain waterproof property.
研究领域:
材料科学
·
农业光学
·
无机非金属材料
·
光生物学
·
功能玻璃
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Bo Zhou,Yasin Muhammad,Dong Ding,Zexiang Liu,Hanlin Hu,Ye Wang,Haizhe Zhong,Yumeng Shi,Henan Li
Multi-ion codoping strategies have been intensively studied for metal halide perovskite optical engineering. Although tunable dual broadband emissions can be achieved by pairing Sb3+/Mn2+ doping centers in metal halide hosts, there have been few reports of highly efficient light emission with a near-unity photoluminescence quantum yield (PLQY). In this study, Mn2+ dopants are incorporated into a Sb3+-doped Rb4CdCl6 system. Tunable dual emissions and a substantial increase in the PLQY from ∼60% to near-unity (98%) are achieved. Energy transfer is strong and localized and occurs only between the Sb3+ donor and the adjacent Mn2+ acceptor. The green self-trapped exciton emission (524 nm) is converted into a red d–d emission (607 nm) without changing the excitation profile. The Sb3+ optical centers without adjacent Mn2+ species maintained their original green emission. Spectroscopic and probabilistic investigations showed that the luminescent and thermally quenched Sb3+ optical centers play identical roles in the energy-transfer process, and nonradiative recombination was successfully inhibited. These findings clarify how Sb3+ and Mn2+ dopants couple in the metal halide host and facilitate the design of high-performance materials that give tunable broadband fluorescence via an energy-transfer process.
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
·
2024
·Vol. 12
·期 21
·2400514
·
IF 8
Guoxiang Xing,Xiaowei Sun,Xiaorui Yang,Feilong Wen,Tianyong Zhang,Bin Li,Shuang Jiang
Recently, the potential circularly polarized luminescence (CPL) property of chiral 2D organic–inorganic hybrid perovskites has garnered attention due to their strong stability. However, the photoluminescence (PL) intensity of chiral 2D perovskite is generally low, which undoubtedly limits its development. Therefore, improving the PL and CPL intensity of chiral 2D perovskite has become an important focal point. To overcome this problem, a series of Mn 2+ -doped R/S-(MPEA) 2 PbBr 4 thin films is successfully synthesized. The Mn 2+ -doped films can produce strong orange emission under UV excitation with the highest photoluminescence quantum yield (PLQY) of 37.37%, a high value among reported chiral 2D perovskites. Moreover, all Mn: (R/S-MPEA) 2 PbBr 4 films show symmetric CPL signals. The flexible regulation of CPL is meaningful for applications, which is generally lacking in current studies. Here, it is found that the strength of CPL can be effectively regulated by doping guanidine (Gua), and the maximum g lum value of 1.4 × 10 −2 and PLQY of 51.31% is achieved, which are the highest among reported chiral 2D perovskites. This work provides a new idea for the development of CPL-active materials and lays the foundation for spin devices based on chiral hybrid 2D perovskite.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
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