Journal of Materials Chemistry C
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2014
·Vol. 2
·期 24
·4812-4817
·
IF 0
Jianbing Zhang,Weipeng Sun,Liping Yin,Xiangshui Miao,Daoli Zhang
A green method for the one-pot direct synthesis of hydrophilic CuInS2 and CuInS2–ZnS colloidal quantum dots was developed employing N,N-dimethylformamide (DMF) as a solvent. Highly reactive H2S gas, in situ generated from the reaction between FeS and H2SO4, was utilized as the sulphur source for the synthesis of hydrophilic CuInS2 quantum dots. Short chain thiols were applied as ligands, reactivity controllers and sulphur sources for the growth of the ZnS shell. The growth of CuInS2 quantum dots experiences a typical Ostwald ripening process, and it should be controlled in 45 min due to the pyrolysis of the ligands. The reaction temperature should not exceed 130 °C. The ZnS shell was grown on CuInS2 quantum dots in a very simple and one-pot approach. Both the luminescence and optical stability were improved substantially after the formation of the ZnS shell. The versatility of this synthetic strategy was demonstrated by extending it to the synthesis of other metal sulphide quantum dots, for instance, CdS and ZnS quantum dots.
研究领域:
材料科学
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化学
✓ 已验证
DOI
APPLIED SURFACE SCIENCE
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2021
·
IF 6.707
Xiangjia Liu,Jin Li
In this study, a ZnO/NiS@NiO/rGO (ZNNG) composite was characterized using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and scanning electron microscopy (SEM). Compared with simple ZnO, ZNNG exhibited stronger green emissions, but no ultraviolet (UV) emission peak was observed. Through a comprehensive analysis of ultraviolet–visible (UV–vis) absorption spectra, Mott Schottky (MS) plots, electron paramagnetic resonance (EPR) spectra, and X-ray photoelectron spectroscopy (XPS) results, it was proved that the stable green emissions of ZnO and its composites originated from the quenching of electrons between Zn interstitial ( Zn i ) and surface oxygen defects. The introduction of NiS@NiO caused the conduction band (CB) and valence band (VB) of ZnO to change to lower energy states, effectively increasing the absorption intensities of ZnO in the visible light, while introducing numerous oxygen-related defects on the surface of ZnO. Further addition of rGO effectively promoted the migration of electrons from the CB to the Fermi energy (E f ). These effects effectively increased the green emission of ZnO and reduced the UV emission. Finally, a proper mechanism for the near-zero band gap NiS@NiO/rGO that can significantly enhance the green emission of ZnO was proposed.
研究领域:
材料科学
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光电子学
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2018
·Vol. 8
·期 8
·612
·
IF 3.504
Dan Zhao,Wenting Ma,Xincai Xiao
The recognition of fingerprints has played an extremely important role in criminal investigations, due to its uniqueness. This paper reports on the recognition of sweat latent fingerprints using green-emitting, environment-friendly carbon dots prepared with DL-malic acid and ethylenediamine, and the exploration of impacting factors in the development process of fingerprints. The experiments showed that better fingerprint images could be obtained when the latent fingerprints are developed in green-emitting carbon dots with pH 9 for 30 min, at room temperature. The reported method was also effective for latent fingerprints on a variety of substrates, as well as for those water-immersed ones, where the developed fingerprint remained stable after long-term preservation. Furthermore, the fluorescent three-dimensional fingerprint image could provide direct and simple evidence on pressing habits. The objective of this paper was to present this method. The method may help to narrow the range of suspects during criminal investigations and in forensic science.Keywords:green;carbon dots;sweat latent fingerprints;forensic science
研究领域:
化学
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法医学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2020
·
IF 4.495
Chao Chen,Zhaofeng Gu,Qinling Li,Yuepin Zhang
Dy 3+ /Tb 3+ co-doped oxyfluoride glass ceramics (GC) containing lithium tetrafluoroyttrium (LiYF 4 ) and yttrium fluoride (YF 3 ) nanograins were prepared by a traditional melt-quenching approach. The crystalline phases and morphologies of the GCs were investigated. The GCs showed enhanced green emission from Tb 3+ ions and the quenching of Dy 3+ emission because of the efficient energy transfer from Dy 3+ to Tb 3+ ions. The electric dipole-dipole interactions were responsible for the energy transfer mechanism between Dy 3+ and Tb 3+ ions. The energy transfer efficiencies of these glass ceramics were calculated from their decay curves. The Dy 3+ /Tb 3+ co-doped oxyfluoride GCs with various visible emissions were found to be potential candidates for white-light emitting diode applications.
研究领域:
材料科学
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光学
✓ 已验证
DOI
高影响因子
JOM
·
2022
·Vol. 74
·期 5
·1934-1944
·
IF 2.597
Liu Peiwen,Fei Zitong,Zhang Yingjie,Dong Peng,Meng Qi,Yang Xi
Developing a green and efficient approach for recovering Li from cathode materials is important in recycling spent LiFePO 4 batteries. A facile and efficient oxidation process was developed to selectively recover Li from spent LiFePO 4 batteries. The common oxidant NaClO was used to avoid using acid or alkali in the leaching process. The leaching rate of Li reached 99.8% under the selective optimal leaching conditions of 0.54 mol/l NaClO, leaching time 60 min, leaching temperature 60°C and solid–liquid ratio 1 g/l. The high leaching efficiency can be ascribed to the combination of oxidability and high pH value of the NaClO solution. Meanwhile, leaching and precipitation were carried out simultaneously in this process, which promoted the leaching reaction. High performance LiFePO 4 /C was resynthesized using the recovered products. The specific capacity of the first discharge at 1 C was 147.1 mAh/g and the capacity retention rate at 1 C was 97.55% after 200 cycles. The oxidation approach is acid free and has low energy consumption for green recovery of spent LiFePO 4 batteries.
研究领域:
材料科学
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环境科学
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能源技术
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
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2022
·Vol. 39
·期 7
·1839-1849
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IF 3.146
Zhang Xiaoting,Zhang Shusheng,Ouyang Gangfeng,Han Runping
A zirconium-based metal organic framework (UiO-66-NH 2 ) was prepared using a greener approach for the removal of hexavalent chromium (Cr(VI)) from solution. The characterization of UiO-66-NH 2 was performed using several methods, and the influence of the solution pH, adsorbent dosage, salt, adsorption time, Cr(VI) concentration and adsorption temperature on adsorption quantity was performed in batch mode. UiO-66-NH 2 can efficiently remove Cr(VI) through the synergistic effect of adsorption and reduction. At pH solution of 1.1 and solid-to-liquid ratio of 2 g·L −1 , the removal rate of 100 mg·L −1 Cr(VI) increased to 95.2%. The maximum adsorption capacity of UiO-66-NH 2 from Langmuir model was 252 mg·g −1 . The adsorption equilibrium process can be well described by Langmuir, Koble-Corrigan and Temkin models, while the kinetic process can be predicted by pseudo-second-order and Elovich model. UiO-66-NH 2 showed a good adsorption capacity in a wide range of pH (pH=1.1–10) and also had better regeneration performance after five cycles using 0.01 mol·L −1 NaOH; consequently, it can be a promising adsorbent for the removal of Cr(VI) from solution.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
GREEN CHEMISTRY
·
2024
·
IF 9.3
Anting Ding,Chuanying Liu,Chengliang Xiao
Palladium and platinum are precious metals (PMs) used in industrial catalysis, and their green recycling is crucial but challenging. In this study, we aimed to create a novel leaching procedure for the environmentally friendly recovery of PMs using AlCl3·6H2O solution. We report here the use of a microwave-assisted AlCl3·6H2O solution to selectively recover Pd and Pt from spent catalysts. In a large-scale setting, our system can recover gram-scale Pd in a single batch. Electron paramagnetic resonance (EPR) and capture experiments revealed the hydroxyl radicals produced by proton dissociation and microwave coordination triggered the oxidative dissolution process. Microwave-assisted AlCl3·6H2O solution leaching and NaBH4 reduction recovered high-purity Pd and Pt separately. In scale-up experiments, the dissolution performance of the microwave-assisted AlCl3·6H2O solution for Pd remained almost unchanged after seven cycles. Our approach uses around 1/50 and 1/20 of the energy and chemical inputs of the conventional hydrometallurgy process, respectively. Strong acids, poisonous cyanide, and volatile organic solvents were not used during the recovery process, enabling an efficient and sustainable PM recovery process and promoting an advanced oxidation process (AOPs) technology for secondary resource recycling.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Chemosensors
·
2022
·Vol. 10
·期 12
·533
·
IF 4.229
Nihui Huang,Guojun Lu,Bihai Bai,Zijun Chen,Min Zhang,Yuechan Li,Chunyan Cao,An Xie
Tungstate and molybdate phosphors have received great attention for their excellent photoluminescent properties and thermal stabilities. In the article, Tb3+-activated tungstate and molybdate green phosphors were prepared by a solid-state reaction method at different caline temperatures and were compared and studied. The crystal structures and the morphologies of samples were characterized by X-ray diffraction (XRD) patterns and field emission scanning electron microscopy (FE-SEM) images. The energy-dispersive spectra (EDS) proved the compositions of the prepared samples. The photoluminescence (PL) spectra showed that the PL excitation spectra of Tb3+-doped Lu2W3O12and Lu2Mo3O12green phosphors consisted of a broad and strong charge transfer band (CTB) and 4f–5d transitions of Tb3+in the ultraviolet (UV) wavelength range and some narrowed excitation peaks from the 4f–4f transition of Tb3+in the near ultraviolet (NUV) wavelength region. The PL emission spectra of the phosphors exhibited the characteristic green emissions owing to the5D4→7F5transition of Tb3+located at about 547 nm. The values of energy gapEgwere calculated based on the diffuse reflection spectra (DRS). The measuring temperature-dependent PL spectra illustrated the thermal stabilities of phosphors. The Tb3+-doped Lu2Mo3O12phosphor presented normal thermal quenching phenomena and the values of the thermal activation energyEawere calculated based on the measuring temperature dependent PL emission spectra. The Tb3+-doped Lu2W3O12phosphor exhibited abnormal thermal enhancing CTB excitation intensity at about 170 °C. Furthermore, the PL decay curves suggested that the lifetime corresponding to the5D4level of Tb3+in the Lu2W3O12host lattice was longer than that in the Lu2Mo3O12host lattice. Compared the Tb3+-doped Lu2Mo3O12phosphor, the Tb3+-doped Lu2W3O12phosphor has shown potential as an application in temperature sensors.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2021
·
IF 8.128
Nan Ma,Wei Li,Balaji Devakumar,Zongjie Zhang,Xiaoyong Huang
White light-emitting diodes (LEDs) are widely used in lighting and display devices, and the exploration of phosphors with excellent luminescence performance and good stability is the key to the development of white LEDs. In this work, we reported novel near-UV-excited green-emitting Ca 2 LuHf 2 (AlO 4 ) 3 :Ce 3+ ,Tb 3+ garnet phosphors with efficient Ce 3+ → Tb 3+ energy transfer. The CLHA:Ce 3+ ,Tb 3+ green phosphors were successfully synthesized by a high-temperature solid-state method, and the phosphors were characterized by X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, elemental mapping, photoluminescence excitation and photoluminescence spectra, the Commission International de I’Eclairage (CIE) chromaticity coordinates, quantum efficiency and temperature-dependent emission spectra. Due to the spin-allowed 4f → 5d transition of Ce 3+ ions, the CLHA:Ce 3+ ,Tb 3+ phosphors exhibited a strong broad excitation band in the 300–470 nm near-ultraviolet (near-UV) range. Under 408 nm excitation, the CLHA:Ce 3+ ,Tb 3+ phosphors showed strong green light with emission center at 543 nm. The mechanism of energy transfer from Ce 3+ to Tb 3+ ions was attributed to quadruple-quadruple interaction. Impressively, the internal quantum efficiency and external quantum efficiency of the optimal CLHA:0.02Ce 3+ ,0.5Tb 3+ green phosphors were measured to be 77.1% and 55.8%, respectively. Finally, using the CLHA:0.02Ce 3+ ,0.5Tb 3+ phosphors as green-emitting color converter, a near-UV-pumped white LED device was fabricated, and under 80 mA driving current the LED device demonstrated bright warm-white light with high color rendering index (93.7), low correlated color temperature (3574 K), CIE chromaticity coordinates (0.3922, 0.3633), and high luminous efficacy (29.35 lm/W).
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2020
·Vol. 12
·期 8
·1735
·
IF 3.426
Ke Li,Huiyu Yang,Lang Jiang,Xin Liu,Peng Lang,Bo Deng,Na Li,Weilin Xu
Dissolving cellulose in water-based green solvent systems is highly desired for further industrial applications. The green solvent glycerin—which contains hydrogen-bonding acceptors—was used together with NaOH and water to dissolve cellulose. This mixed aqueous solution of NaOH and glycerin was employed as the new green solvent system for three celluloses with different degree of polymerization. FTIR (Fourier-transform infrared), XRD (X-ray diffractometer) and TGA (thermogravimetric analysis) were used to characterize the difference between cellulose before and after regenerated by HCl. A UbbeloHde viscometer was used to measure the molecule weight of three different kinds of cellulose with the polymerization degree of 550, 600 and 1120. This solvent system is useful to dissolve cellulose with averaged molecule weight up to 2.08 × 105g/mol.Keywords:cellulose;glycerin;dissolution;green solvent;aqueous solution
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2023
·
IF 4.4
Xiang Mao,Xia Zhao,Hao Hu,Zequan Li,Wei Xiong,Yujiao Wei,Wei Gao
Work to combat counterfeiting has always been crucial to defending the interests of the public. The usual anti-counterfeiting marks are now fundamental and easy to imitate. Therefore, it is more beneficial to anti-counterfeiting work to develop an anti-counterfeiting mark with more variations to make forgery more difficult. Due to its exceptional stability and fluorescence variability, carbon dots (CDs), a newly developed fluorescent material, offer a wide range of potential applications in anti-counterfeiting. However, there currently needs to be more CD applications in multi-level anti-counterfeiting, and additional issues include high cost and environmental contamination. Therefore, considering the problems of green environmental protection and cost, CDs with excellent green (530 nm) and blue (475 nm, 486 nm) luminescence properties were prepared by a one-step reaction of m-phenylenediamine and glucose. The average fluorescence lifespan is longer than 5 ns, and the optimal quantum yield can reach 37%. Due to the large number of protonated amino groups and surface carboxyl functional groups, the prepared carbon dots exhibit green and blue fluorescence emission modes under acidic and alkaline conditions, respectively. Based on this situation, we produced CD ink and successfully used it for multi-level anti-counterfeiting.
研究领域:
材料科学
·
化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANOMETALLIC CHEMISTRY
·
2025
·
IF 2.4
Ke Yang,Sisi Cheng,Shijia Li,Kun Zhu,Ziqin Yao
The influencing factors of ZIF-8 synthesis were systematically investigated by the green synthesis method and the samples were also compared with ZIF-8 synthesized in other ways, and an optimal synthesis route was found by exploring the synthesis conditions. On this basis, the synthesis mechanism of ZIF-8 was analyzed. The research results show that the key influencing factors in the reaction process are the amount of NaOH and the pH value of the system. Different amounts of NaOH will produce different intermediates, and these intermediates further affect the pH value of the entire reaction system. The pH value of the system plays a decisive role in the deprotonation process of the ligand in the reaction, and this process is the key to whether the ZIF-8 structure can be formed. It is worth mentioning that the ZIF - 8 synthesized in this study demonstrates varying removal performances for different dyes under different conditions. Under specific conditions, it exhibits the maximum removal rate for Rhodamine B (RhB), reaching 99.97 %. This excellent removal performance is closely associated with the pore - structure characteristics of the synthesized material, which fully indicates that the ZIF - 8 synthesized through the green route has certain application potential and promising application prospects in related fields.
研究领域:
材料科学
·
环境科学
✓ 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）