Applied Materials Today
·
2024
·
IF 7.2
Huajiang Hu,Jiurong Li,Xiao Gong
Due to their unique fluorescence properties and wide range of applications, carbon dots (CDs) have emerged as a prominent research subject. Acid reagents have traditionally been regarded as versatile means to facilitate the carbonization and polymerization of CDs, resulting in increased carbonization and polymerization levels, which in turn cause a redshift in the luminescence of CDs. However, there has been limited investigation into the impact of excess acid reagents on CDs luminescence. In this study, we discovered that the addition of excess acid reagent, in the presence of oxygen-containing functional groups, does not enhance the graphitization of CDs, but rather, it has the opposite effect. Excess acid reagents prevent CDs polymerization and reduce the content of graphite-N in the CDs. Simultaneously, excess acid reagent leads to an increase in oxygen-containing functional groups on the surface of the CDs, resulting in a blueshift in luminescence. Building upon these findings, we have devised a synthesis scheme for full-color CDs that cover nearly the entire visible light spectrum. Furthermore, leveraging the diverse color range, we have also employed these CDs for anti-counterfeiting encryption and LEDs applications.
研究领域:
材料科学
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光学
·
化学
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
You Zhang,Kun Zhao,Haoyu Zhu,Qiong Xi,Nian Fu,Dawei Wang,Jinxing Zhao,Li Guan,Yunfei Zhuang,Xu Li
White light-emitting diodes (WLEDs) have emerged as a leading technology for healthy lighting and advanced displays. Nevertheless, the poor thermal stability of blue-emitting components remains a significant bottleneck, hindering their broader adoption in demanding environments. Here, we have prepared a series of Ca 3 Al 2 O 6 :Ce 3+ phosphors by high temperature solid-state method. Substituting the [Al 3+ –O 2- ] ionic pair with [Si 4+ –N 3- ] in the Ca 3 Al 2 O 6 host lattice via a charge-compensated strategy achieves a 1.75 times enhancement in thermal stability compared to the pristine material, while simultaneously inducing a blue-shifted emission spectrum (Δλ = 30 nm). The enhanced thermal stability originates from increased lattice rigidity, while the blue spectral shift arises from modulated crystal field splitting decrease. These mechanistic insights provide a foundational strategy for designing ultra-stable blue phosphors compatible with high-power WLED applications.
研究领域:
材料科学
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光学工程
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DOI
高影响因子
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
·
2015
·Vol. 2015
·期 31
·6806-6810
·
IF 3.065
Li Liu,Yuhang Yao,Xuefang Zhang,Ce Hao
Graphical A highly ordered 3D framework from 1,5-naphthalenedisulfonate (1,5-NDS) and cucurbit[6]uril (CB[6]) is synthesized, wherein the 1,5-NDS anions act as linkers to connect the CB[6] units together through C–H ··· O H-bonds. The fluorescence wavelength of the assembly structure is blueshifted relative to that of 1,5-NDS and the fluorescence intensity is decreased, which are ascribed to the formed H-bonds. A highly ordered 3D framework from 1,5-naphthalenedisulfonate (1,5-NDS) and cucurbit[6]uril was synthesized and structurally determined by single-crystal X-ray diffraction analysis. The crystal structure demonstrates that the 1,5-NDS anions act as linkers to connect the cucurbit[6]uril units together through C–H ··· O hydrogen bonds between the 1,5-NDS anions and cucurbit[6]uril. Furthermore, with 1,5-NDS as the fluorophore, the fluorescence properties of the corresponding assembly structure were investigated in the solid state. Relative to that observed for 1,5-NDS, the assembly exhibited a blueshift in the fluorescence wavelength from λ = 406 to 340 nm along with decreased fluorescence intensity. Theoretical calculations were in good agreement with the experimental results and disclosed that the fluorescence mechanism of the assembly structure could be ascribed to the hydrogen bonds formed between the 1,5-NDS anion and cucurbit[6]uril.
研究领域:
化学
·
材料科学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Xin Wang,Tao Yang,Xinmei Hou,Yapeng Zheng,Enhui Wang,Zhengtao Du,Sheng Cao,Hailong Wang
Silicon carbide nanowires (SiC NWs) were successfully synthesized using graphene and Si powder as raw materials in NaCl–NaF at 1300–1400 °C for 6 h. The synthesized SiC NWs have two crystal phases due to the presence of molten salt, which formed the 2H/3C–SiC heterojunction structure. The possible synthesis mechanism of SiC NWs is “dissolution-diffusion-reaction”. Besides, photoluminescence (PL) spectra of 2H/3C–SiC heterojunction NWs show that the main emission peak has a significant blue shift, locating in 350–600 nm. The main reason is caused by the defects of 2H/3C–SiC heterojunction structure and the spontaneous polarization of 2H–SiC nano segments.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
OPTIK
·
2015
·
IF 0.677
Hongyan Zhang,Zhenhong Jia,Xiaoyi Lv,Rong Wu,Peng Li,Jing Wang
The influence of permeable layer number of porous silicon microcavity (PSM) on the reflectance spectrum has been carried out from both simulations and experiments. The increase of the effective refractive index of the first porous silicon (PS) layer of PSM will causes a blue shift for the reflectance spectrum. With one more layer refractive index increasing, the blue shift becomes less, and it will shift to a higher wavelength when the layer number becomes large enough. This study would be helpful for simple fabrication of highly sensitive, fast responsible biosensors based on the blue shift of reflectance spectrum, and such fabricated Au/PSM substrate of multilayer PS might have a potential to detect minor biomolecules by means of surface state effects.
研究领域:
材料科学
·
生物医学工程
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产品关联
DOI
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2014
·
IF 6.451
Kanghui Tan,Guang Yang,Huide Chen,Pengfei Shen,Yucheng Huang,Yunsheng Xia
By combination of experiments and density functional theory calculations, we present a simple but effective “facet dependent binding and etching” strategy for non-enzymatic and non-aggregated colorimetric sensing of blood uric acid (UA), using unmodified Ag nanoprisms as the signal readout. In the absence of UA, the triangular Ag nanoprisms are etched alongside (1 1 0) facets by H 2 O 2 and form round nanodiscs , and a more than 160 nm surface plasmon resonance (SPR) blue shift is observed. Because of special affinity between UA and side facets of the Ag nanoprisms, pre-added UA can well protect the Ag nanoprisms from etching. Such protection effect can be used for well quantifying UA in the range of 10–3000 nM, based on the inverse proportion of the SPR blue shift with the added analyte. Due to very thin plate morphology (5 nm) and facet dependent binding/etching effects of the Ag nanoprisms, the sensing system has ultrahigh sensitivity. The detection limit is only 10 nM, which is about 2 to 4 orders of magnitude lower than that of previous colorimetric sensing systems. In addition to accurate quantitation, the proposed strategy can conveniently discriminate the patient of hyperuricemia from normal person by naked eyes. So, the present simple, low-cost and visualized UA chemosensor has great potential in the applications for point-of-care diagnostics.
研究领域:
生物化学
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医学诊断
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纳米技术
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产品关联
DOI
PubMed
高影响因子
PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
·
2014
·Vol. 32
·期 1
·72-79
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IF 0.537
Hao Huang,Cuicui Du,Hongyan Shi,Xun Feng,Jin Li,Yanlei Tan,Wenbo Song
Uniform water-soluble monolayer MoS 2 quantum dots (MQDs) with lateral sizes of ≈2.1 nm, a clearly zigzag-terminated edge, and a hexagonal lattice structure are achieved using ammonium molybdate, thiourea, and N-acetyl- l -cysteine (NAC) as precursors and the capping reagent in a facile one-pot hydrothermal approach. MQDs have good dispersity and high stability in aqueous suspension and exhibit a significantly larger direct bandgap (3.96 eV) compared to monolayer MoS 2 nanosheets (1.89 eV). Pronounced blue-shifts in the wavelengths of both the excitonic absorption and intrinsic state emission with activated strong luminescence at room temperature beyond monolayer MoS 2 nanosheets is demonstrated. Unusual upconversion photoluminescence is also observed and is caused by two successive transfers of energy from the near-infrared (NIR) absorption generated by the NAC capping reagent to the hexagonal structure of MQDs. Additional optical properties of MQDs may provide numerous exciting technological applications. Here, MQDs are demonstrated as a highly selective fluorescent reagent for detecting tetracycline hydrochloride under UV and NIR irradiation.
研究领域:
材料科学
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光学
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生物医学
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DOI
高影响因子
ACS Omega
·
2019
·
IF 2.584
Gang He,Linlin Du,Yongyang Gong,Yuanli Liu,Chuanbai Yu,Chun Wei,Wang Zhang Yuan
Mechanochromic luminogens are of significant importance in both academic and technical aspects. Thus far, most mechanochromic compounds exhibit bathochromically shifted emission upon grinding; the examples of those that exhibit blue-shifted emission still remain limited. Herein, a donor–acceptor–donor (D–A–D)-structured conjugate, namely 4,7-di(2-thienyl)-2,1,3-benzothiadiazole (DTBT), comprising benzobis(1,2,5-thiadiazole) and thiophene units, has been carefully synthesized and investigated. DTBT exhibits typical intramolecular charge transfer (ICT) characteristics, crystallization-induced phosphorescence (CIP), and remarkable mechanochromism. Although it merely emits fluorescence in solutions with distinct ICT features, its crystals demonstrate bright-red room-temperature phosphorescence (616 nm) with efficiency up to 25.0% and generate yellow excimer fluorescence (578 nm) upon mechanical grinding, accompanying decreased lifetimes from 10.9 μs to 3.5 ns and a blue-shifted emission of 38 nm. These results highly indicate the feasibility to fabricate novel CIP luminogens with blue-shifted mechanochromism.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
POLYMER TESTING
·
2022
·
IF 4.931
Shuangshuang Liu,Jiaojiao Wang,Lele Wang,Xianlin Wang,Xinhui Zhou,Jin Wang
Polarized fluorescent polymers can be promisingly used for many applications. In this work, the polarized fluorescent poly[2-methoxy,5-(2′-ethylhexyloxy)-1,4-phenylene vinylene]@MOF (MEH-PPV@MOF) composites were synthesized via the direct chain-introduction method. Firstly, long-range ordered porous metal-organic framework (MOF) crystals were synthesized. Through morphology observation and X-ray diffraction measurement, the water stability, thermal stability and structural stability of synthesized MOF were analyzed, to determine the preservation treatment of the material and the process parameters of introducing polymer chains in the subsequent experiment. Then, the MEH-PPV chains were directly introduced into the MOF channels via a solution-mediated incorporation approach. The measurement results of powder X-ray diffraction, nitrogen adsorption and Fourier transform infrared spectroscopy showed that the MEH-PPV chains were successfully introduced into the MOF channels. Finally, the fluorescent properties of the MEH-PPV@MOF composites were characterized via the photoluminescence spectroscopy. It was found that the accommodation of MEH-PPV chains within 1-D channels of MOF led to a strong blue-shift of the photoluminescence spectrum, due to the quantum confinement effect. Also, the polarization ratio calculated from the polarization luminescence spectra of the composites was 2.215. This indicates that the MEH-PPV@MOF composites prepared by the direct chain-introduction method with the help of the solution-mediated approach have good photoluminescence anisotropy.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
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2017
·
IF 1.109
M.M. Mikhailov,V.V. Neshchimenko,C. Li,V.A. Vlasov
The effect on band gap (E g ) and crystal structure of ZnO modified by Al 2 O 3 , ZrO 2 , SiO 2 , CeO 2 , TiO 2 and Y 2 O 3 nanoparticles at concentrations less than 30 wt% has been investigated. Established that change of E g reach to 0.03 eV and determined by charge of cations and their radius, as well as the concentration of the nanoparticles. Lattice parameters changes at modifying by nanoparticles with a smaller and larger radius of cations than the ion Zn 2+ . Influence of 100 keV protons irradiation result in blue shift in absorption edge of polycrystalline zinc oxide modified by Al 2 O 3 , ZrO 2 , SiO 2 , CeO 2 , TiO 2 and Y 2 O 3 nanoparticles.
研究领域:
材料科学
·
物理学
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产品关联
DOI
高影响因子
NATURE MATERIALS
·
2020
·Vol. 20
·期 2
·175-180
·
IF 38.663
Chen Chengjian,Chi Zhenguo,Chong Kok Chan,Batsanov Andrei S.,Yang Zhan,Mao Zhu,Yang Zhiyong,Liu Bin
Commercial carbazole has been widely used to synthesize organic functional materials that have led to recent breakthroughs in ultralong organic phosphorescence 1 , thermally activated delayed fluorescence 2 , 3 , organic luminescent radicals 4 and organic semiconductor lasers 5 . However, the impact of low-concentration isomeric impurities present within commercial batches on the properties of the synthesized molecules requires further analysis. Here, we have synthesized highly pure carbazole and observed that its fluorescence is blueshifted by 54 nm with respect to commercial samples and its room-temperature ultralong phosphorescence almost disappears 6 . We discover that such differences are due to the presence of a carbazole isomeric impurity in commercial carbazole sources, with concentrations <0.5 mol%. Ten representative carbazole derivatives synthesized from the highly pure carbazole failed to show the ultralong phosphorescence reported in the literature 1 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 . However, the phosphorescence was recovered by adding 0.1 mol% isomers, which act as charge traps. Investigating the role of the isomers may therefore provide alternative insights into the mechanisms behind ultralong organic phosphorescence 1 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 .
研究领域:
有机材料科学
·
光化学
·
材料化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2024
·
IF 6.1
Lizhong He,Tingting Dong,Xiaoyang Hu,Zibao Gan
Precisely tailoring the structure of bimetal nanoclusters (NCs) at the atomic level has been proven to be an effective way to tune their physicochemical properties; however, achieving this remains challenging. Herein, the regulation from the reported Ag26Pt(2-EBT)18(PPh3)6 (Ag26Pt) to Ag16Pt(2-EBT)6(dppm)4Cl2 (Ag16Pt; 2-EBTH = 2-ethylbenzenethiol; dppm = bis-(diphenylphosphino)methane) NC was instantaneously (within one minute) realized through an asymmetrical pseudo-ligand exchange strategy. Single crystal X-ray crystallography (SCXC) combined with X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) confirmed its composition and structure. The target Ag16Pt NC consists of a Pt@Ag12 icosahedral core capped by a ligand shell of a pair of dimetric -SR-Ag-SR-Ag-SR- staple motifs, four dppm ligands, and two chlorine atoms. Their geometrical, electronic and crystallographical structures were comparatively investigated before and after regulation, which also provides some clues for understanding the blueshift of the emission center (Ag26Pt: 845 nm vs. Ag16Pt: 675 nm). This work provides important insights into the regulation of structures and photoluminescence of bimetal NCs protected by co-ligands.
研究领域:
材料科学
·
化学
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产品关联
DOI
高影响因子
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