Advanced Optical Materials
·
2024
·
IF 8
Xinran Wang,Heng Dai,Baozhu Li,Xuhui Xu,Jian Zhang,Daiyuan Liu,Yichun Liu,Zhichao Liu
Optical materials have attracted much attention in anti-counterfeiting applications due to their visualization and multi-emission modes. However, the unit occupancy predestines the material to only monochromatic emission, inhibiting the application of optical materials in advanced information encryption. Here, a green to yellow to deep-red phosphor is reported in a Mn 2+ -activated garnet compound Ca 2 YMgScSi 3 O 12 : Mn 2+ (CYMSS: Mn 2+ ), originating from the abundant lattice sites occupying within the crystal structure by Mn 2+ ions. Three different photoluminescence (PL) emission bands peaked at 517, 576, and 720 nm from 4 T 1 (G) → 6 A 1 (S) are observed, which are attributed to the substitution of [Sc/MgO 6 ] octahedron and [Ca/YO 8 ] dodecahedron sites by Mn 2+ ions, respectively. Hence, tunable emissions from green to deep-red are realized in single Mn 2+ doping by switching the excitation source of ultraviolet (UV)/blue and X-ray, which can be further regulated by varying the Mn 2+ concentration. Multi-position occupying, color-tunable light-emitting materials offer the possibility of more advanced optical information encryption.
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 HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Wen-Xiong Li,Hai-Jun Zhang,Xiao-Ping Hu,Wen-Xue Yang,Zhou Cheng,Chang-Qiong Xie
The intumescent flame retardant (IFR) with ammonium polyphosphate (APP) as the main component has many defects in practical applications, more than that, APP can be traced to non-renewable phosphate rock resources. For the foregoing reasons, the melamine phytate supramolecular nanosheet flame retardant incorporating manganese ion (PAMA-Mn) was successfully prepared with a facile and environmental friendly hydrothermal procedure based on renewable bio-based material phytic acid (PA). The flame retardant polypropylene composite (PPI) with 13.5 wt% APP and 4.5 wt% pentaerythritol (PER) failed to the UL-94 test, and its limiting oxygen index (LOI) value was only 26.5%. After 33 wt% of APP was replaced by PAMA-Mn, the PPMn33 incorporating only 18 wt% flame retardant additives passed the UL-94 V-0 rating, and its LOI value was increased to 31.9%. Compared with PP, pHRR and pSPR values of PPMn33 were reduced by 56% and 23%, respectively. The fire retardant mechanism of PPMn33 was thoroughly discussed via a variety of characterization methods. It was found that the peak of the Gram-Schmidt curve of PPMn33 was drastically reduced by 49% relative to that of PPI, indicating a remarkably decrease of combustible volatile products owing to the incorporation of PAMA-Mn, thereby rapidly reducing the fire hazard risk.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Chemistry
·
2021
·
IF 8.301
Nan Ma,Wei Li,Balaji Devakumar,Zongjie Zhang,Xiaoyong Huang
The development of high-brightness far-red-emitting phosphors with emission wavelength within 650–750 nm is of great significance for indoor plant cultivation light-emitting diode (LED) lighting. Herein, we demonstrate a novel efficient far-red-emitting phosphors CaMg 2 La 2 W 2 O 12 :Mn 4+ (abbreviated as CMLW:Mn 4+ ) toward application in plant cultivation LEDs. Interestingly, the CMLW:Mn 4+ phosphors show a broad excitation band in the 250–600 nm spectral range with two peaks at 352 and 479 nm, indicating they could be efficiently excited by near-ultraviolet and blue light. Under 352 nm excitation, the CMLW:Mn 4+ phosphors exhibit an intense far-red emission band in the wavelength range of 650–800 nm peaking at 708 nm, corresponding to the 2 E g → 4 A 2g transition of Mn 4+ ions. Mn 4+ doping concentration-dependent luminescence properties are studied in detail, and the concentration quenching mechanism is also investigated. Particularly, the internal quantum efficiency of CMLW:Mn 4+ phosphors reaches as high as 44%, and their PL spectra match well with the absorption spectrum of phytochrome P FR (P FR stands for far-red-absorbing form of phytochrome). Furthermore, a prototype LED device is fabricated by coating the as-prepared CMLW:0.8%Mn 4+ phosphors on a 460 nm blue LED chip, which produces bright far-red emissions upon 20–300 mA driving currents. This work reveals that the newly discovered far-red-emitting CMLW:Mn 4+ phosphors hold great potential for application in indoor plant cultivation.
研究领域:
材料科学
·
植物学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Water
·
2024
·Vol. 16
·期 14
·1994
·
IF 3
Hongbin Wang,Shijie Kuang,Youlun Su,Xu Ren,Bowen Yang,Yongliang Sun
Diclofenac (DCF) is often detected in diverse aquatic bodies, and ineffective management can lead to detrimental effects on human health and ecosystems. In this study, degradation of DCF by Fe(III) and Mn(II) activating bisulfite (BS) was investigated. In the Fe(III)/Mn(II)/BS system, 93.4% DCF was degraded at 200 μM BS within 120 s, and additional research on 1000 μM BS achieved 88.4% degradation efficacy. Moreover, kinetics fitting of DCF degradation with the different BS concentrations was studied to find the two highest reaction rates (200 and 1000 μM,kobs= 0.0297 and 0.0317 s−1, respectively). Whereafter, SO4•−and Mn(III) were identified as the main active species at these two concentrations, respectively. Density functional theory (DFT) calculations, molecular frontier orbital theory, and surface electrostatic potential (ESP) forecast electrophilic attack sites. DCF degradation pathways by radical and non-radical ways were proposed by attack site prediction and thirteen intermediates identified by UPLC-QTOF-MS. ECOSAR software 2.2 was used for toxicity assessment. This work studied DCF degradation by the Fe(III)/Mn(II)/BS process in the presence of different concentrations of BS, providing a new insight into water purification.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2018
·
IF 4.484
Xianwei Bai,Haizheng Zhong,Bingkun Chen,Cheng Chen,Junbo Han,Ruosheng Zeng,Bingsuo Zou
Pb-free inorganic–organic perovskite materials - C10H12N2MnBr4 (compound 1) and C5H6NMnBr3 (compound 2) - with different structures were obtained by using pyridine and manganese bromide as raw materials. The single-crystal X-ray diffraction analyses revealed their different lattices in space groups. Compound 1 - Mn tetra-Br-coordinated with two pyridines - presented an isolated mononuclear structure. Its temperature-dependent photoluminescence spectra exhibited an emission band at 523 nm from the lowest d–d crystal field transition of Mn and a higher energy emission at 493 nm from its vibronic state at low temperature. Compound 2 - Mn octahedra-Br-coordinated with a minor pyridine - face-shares with linear chains, which were separated by pyridine molecules. Its emission peak occurred at around 650 nm, in which ferromagnetism was observed. The lifetimes of d–d transition for a single manganese ion and the Mn cluster were presented.
研究领域:
材料科学
·
光学
·
无机化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·
IF 2.758
Renping Cao,Xiangfeng Ceng,Jijun Huang,Xiuwen Xia,Siling Guo,Jingwei Fu
Novel double-perovskite Sr 2 ZnWO 6 :Mn 4+ (SZW:Mn 4+ ) phosphor is synthesized by high-temperature solid-state reaction method in air. SZW:Mn 4+ phosphor with excitation at 325 and 526 nm emits deep-red light, the chromaticity coordinate is (0.7315,0.2685), and the emission band peaking at ~702 nm within the range 640–760 nm is assigned to the 2 E→ 4 A 2 transition of Mn 4+ ion. The influences of “Mn 4+ - ligand” bonding and crystal field strength to emission properties of Mn 4+ ion are analyzed. The optimal Mn 4+ ion concentration in SZW:Mn 4+ phosphor is ~0.8 mol%. Lifetime of SZW:Mn 4+ phosphor decreases from 554.77 to 401.35 μs with increasing Mn 4+ ion concentration in the range of 0.2–1.0 mol%. The lifetime data and decay curves indicate that there is only a single type of Mn 4+ ion luminescent center in SZW:Mn 4+ phosphor. The luminous mechanism of SZW:Mn 4+ phosphor is analyzed by Tanabe-Sugano energy level diagram of Mn 4+ in the octahedron together with the simple energy level diagram. The experimental results are helpful to research the influences of the neighboring coordination environment around Mn 4+ and host crystal structure to the luminescence properties of Mn 4+ ion and to deeply understand other Mn 4+ -dopedmaterials.
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
·
2022
·
IF 5.532
Xianju Zhou,Shouchun Zhao,Jie Zhang,Guotao Xiang,Sha Jiang,Li Li,Yongjie Wang,Yanhong Li,Chuan Jing,Lu Yao,Hongmei Yang,Zhen Wang
As a new generation of luminous material , perovskite quantum dots (PQDs) possess many excellent properties. However, PQDs suffer from dramatic decrease of optical performance when affected by high temperature. In this paper, methamidine acetate (FA + ) and manganese divalent cation (Mn 2+ ) codoped CsPbCl 3 quantum dots (QDs) were synthesized. The introduced FA + and Mn 2+ were designed to substitute Cs + (A sites) and Pb 2+ (B sites), respectively. By comparison with CsPbCl 3 :Mn 2+ QDs, the results show that the CsPbCl 3 :FA + ,Mn 2+ QDs improve the blue exciton luminescence by 15% and the red Mn 2+ ions luminescence by 37%. Furthermore, CsPbCl 3 :FA + ,Mn 2+ QDs demonstrate super thermal stability by maintaining 97% of Mn 2+ emission when the temperature is raised to 70 °C even after 6 thermal cycles. Simultaneously, the UV light and water stability of CsPbCl 3 :FA + ,Mn 2+ QDs have also been obviously enhanced. The powder of the coped PQDs have been fabricated into a white LED which exhibits Color Rendering Index (CRI) of 88.2 and Correlated Color Temperature (CCT) of 5745 K. It shows that CsPbCl 3 :FA + ,Mn 2+ QDs not only reduce the Pb 2+ ions toxicity problem but also boost the thermal stability and thermal cyclability, which may open up more possibilities for the applications in optoelectronic devices.
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
·
2022
·Vol. 51
·期 24
·9501-9510
·
IF 4.569
Jianhong Ding,Meng Kuang,Shuifu Liu,Ziheng Zhang,Kangrong Huang,Jiansheng Huo,Haiyong Ni,Qiuhong Zhang,Junhao Li
Developing novel luminescent materials with ideal properties is an endless project, urged by growing requirements of advances in energy saving, healthy lighting and environmental friendliness. Herein, a series of ScCaOBO3:Ce3+,Mn2+ phosphors with excellent luminescence properties were synthesized by the high temperature solid state method. X-ray diffraction was applied to analyse the phase composition of the obtained phosphors. The morphology and dopant distribution were observed by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS), respectively. The Rietveld refinements and luminescence spectra indicate that Ce3+ preferentially occupies the Sc3+ site and produces a blue emission band at around 460 nm, which originates from the characteristic 5d–4f transitions, while Mn2+ preferentially occupies the Ca2+ site and emits red light due to its characteristic 4T1(4G)–6A1(6S) transitions. Upon excitation at 354 nm, both Ce3+ and Mn2+ emissions can be obtained and further investigations evidenced that the broad and intense light emission of Mn2+ located in the red spectral region is the result of energy transfer from Ce3+ to Mn2+. Theoretical calculations reveal that the energy transfer process from Ce3+ to Mn2+ is of the resonance type and is governed by electric dipole–dipole interactions. Since the ScCaOBO3:Ce3+,Mn2+ phosphors are capable of producing broadband emissions that widely cover the blue and red spectral regions, the introduction of a green light-emitting phosphor CMA:Tb3+ can conveniently generate high quality white light. Therefore, a white light-emitting diode device with extremely high color rendering indices, Ra = 93.7 and R9 = 91.9, was successfully obtained.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Renping Cao,Yaqin Ran,Xinyan Lv,Longxiang Xu,Huijun Wan,Qianglin Hu,Ting Chen,Chunyan Cao
A series of single doped (Ce 3+ ) and co-doped (Ce 3+ and Mn 2+ ) Ca 8 ZnLa(PO 4 ) 7 (CZLP) phosphors are synthesized in air by using the solid-state reaction method. The crystal structure, morphology, and luminescence properties of the samples are investigated. The blue emission of CZLP:Ce 3+ phosphors is observed in the range of 325–450 nm when they are excited by 315 nm ultraviolet (UV) light, and the optimal Ce 3+ concentration is about 8 mol%. With excitation at 315 nm, a tunable color emission of CZLP:8%Ce 3+ , yMn 2+ phosphors from blue to red is displayed when Mn 2+ concentration is changed from 0 to 12 mol%, and the corresponding chromaticity coordinates are varied from (0.1635, 0.0118) to (0.5885, 0.2829). The spectral propertires and lifetimes confirm the energy transfer (ET) process from Ce 3+ to Mn 2+ ions in CZLP:8%Ce 3+ , Mn 2+ phosphor. The luminous mechanism and ET phenomenon are explained by using the Tanabe-Sugano diagram of Mn 2+ ion and the energy level diagrams of Ce 3+ and Mn 2+ ions. The experimental results are favorable for the improving and adjusting of luminescence properties of other phosphors.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Optical Materials
·
2022
·Vol. 10
·期 9
·2102851
·
IF 10.05
Weijiang Gan,Bo-Mei Liu,Lin Huang,Sunqi Lou,Jian Zhang,Zhi Zhou,Jing Wang
Lead-free double perovskites (DPs) with unique optical properties are of interest for broad applications. However, improving near-infrared (NIR) photoluminescence (PL) in lead-free DPs is still a challenge. Herein, in order to increase the NIR PL intensity and extend the infrared multicolor luminescence, transition metal Mn 2+ is doped into Cs 2 NaBi 1− x Er x Cl 6 lead-free DPs. Steady-state and time-resolved PL studies show that efficient energy transfer from Mn 2+ to Er 3+ is obtained, leading to NIR PL at ≈1.54 µm can be enhanced 11-fold compared to Er 3+ singly alloyed sample and a PL quantum yield of ≈14.2%. Moreover, the Mn 2+ -mediated sensitized strategy can expand to other NIR lanthanide ions (Ho 3+ at ≈0.98 µm or Nd 3+ at ≈1.07 µm). The as-synthesized Mn 2+ doped Cs 2 NaBi 1− x Er x Cl 6 DPs exhibit robust stability against heat, ultraviolet light, and environmental oxygen/moisture. Finally, the lead-free DPs phosphor-converted multifunctional white light-emitting diode device containing visible and NIR light is fabricated. This work guides constructing energy transfer pathways in DPs and opens new perspectives for the development of lanthanide-functionalized DPs as promising materials for optoelectronic devices operating in the NIR region.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2018
·
IF 7.082
Yingbo Liu,Daiyong Chao,Liang Zhou,Yanan Li,Ruiping Deng,Hongjie Zhang
The development of high quantum yield (QY) carbon dots (CDs) is a key requirement for applications. However, how to engineer well-defined absorption band in visible region is a critical challenge to obtaining highly efficient long wavelength emissive CDs. In this work, the strategies of solvent-tuning absorption band and manganese ions-enhancing optical performance are introduced to prepare yellow emissive CDs. The utilization of toluene as solvent is a basis for achieving absorption band at 435 nm and realizing yellow emissive CDs with QY of 46%. Addition of manganese ions increase the degree of conjugated sp 2 -domians and surface states, further enhancing QY up to 68.6%. Using the yellow emissive CDs, a UV-pumped light-emitting diode (LED) was fabricated based on a 395 nm LED chip. The LED shows warm light with correlated color temperature (CCT) of 1596 K and color purity of 99%. This work provides a new insight for the development of high-quality CDs with versatile properties in pursuit of promising 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
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Aysh Y. Madkhli
To generate red emissions, manganese (IV) ions have recently gained recognition as potent non-rare-earth activators. However, the oxide and fluoride hosts that offer suitable environments for Mn 4+ require careful preparation, involving precise control of reaction parameters like redox equilibrium and temperature. In the current work, we show simultaneous oxidation of Mn 2+ to Mn 4+ by devitrification of glassy Na 2 Ge 4 O 9 : Mn under moderate atmospheric conditions and under the argon atmosphere. The G-sample was devitrified via thermal treatment after the parent glass, which shares the same chemical formula as dilithium tetragermanate (Na 2 Ge 4 O 9 ), was created through the use of traditional melt-quenching (MQ). Optical spectroscopy and electron paramagnetic resonance (EPR) spectroscopic are utilized to confirm the Mn 2+ oxidation to Mn 4+ from glass stat to glass ceramic after thermal treatment. Due to the transition from Mn 2+ to Mn 4+ , a sharp 668 nm emission peak is recorded whereas the red emission peaking at 611 nm monitored in glass is steadily reduced. The temperature-dependent PL spectra of the Na 2 Ge 4 O 9 :0.1Mn +4 , red-emitting GC in the temperature range ∼295–490 K were recorded. The PL emission intensity decreases gradually with increasing the temperature. The technique showcased for producing Na 2 Ge 4 O 9 :Mn 4+ phosphors could be expanded to synthesize other phosphors incorporating activators possessing a high oxidation state.
研究领域:
材料科学
·
光学
✓ 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）