Journal of Materials Chemistry A
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2019
·Vol. 7
·期 11
·6467-6474
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IF 10.733
Naveed Ur Rahman,Wasim Ullah Khan,Shaukat Khan,Xiaojie Chen,Javid Khan,Juan Zhao,Zhiyong Yang,Mingmei Wu,Zhenguo Chi
Metal halide perovskite solar cells (PSCs) have been studied over the past few years and high power conversion efficiency (PCE) has been achieved. However, the adverse instability remains a key factor restricting wider application of PSCs. Herein, we report, for the first time, a viable strategy to incorporate a down conversion nanophosphor Sr2CeO4:Eu3+ (SCOE) into PSCs, and more importantly SCOE enables the PSCs with improvement in photovoltaic performance and UV-light stability. The SCOE-coated PSCs achieve a high current density of 23.70 mA cm−2 and a high PCE of 18.95%, which are increased by 9% and 14.15%, respectively, when compared to those of control devices (without an SCOE layer). Moreover, the SCOE-based PSCs retain 80% of their initial PCE value after 70 hours under UV-light irradiation and retain 78% of their initial PCE value after 75 days under ambient environment with 20–25% relative humidity. These results suggest that the incorporated SCOE down conversion material is a functional component of PSCs which broadens the solar spectral response, improving photovoltaic performance, and reduces UV-light-induced photodegradation by converting UV light to visible light, prolonging the device stability.
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高影响因子
JOURNAL OF LUMINESCENCE
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2019
·
IF 2.961
Hai Guo,Zhigang Zheng,Liming Teng,Rongfei Wei,Fangfang Hu
In this paper, a series of Bi 3+ and Eu 3+ single-doped as well as Bi 3+ ,Eu 3+ co-doped Ba 9 Y 2 Si 6 O 24 samples were synthesized through a simple high-temperature solid-state reaction method. Their crystal structures, morphologies, luminescent properties, temperature-dependent emission spectra , decay curves and quantum efficiencies were investigated in detail. Upon ultraviolet light excitation, Bi 3+ single-doped samples exhibited blue and green emissions peaking at 408 and 501 nm, corresponding to the 3 P 1 – 1 S 0 transition of Bi 3+ ions. The spectral analysis indicated that there were two different luminescent centers of Bi 3+ ions due to different occupancies in Ba 9 Y 2 Si 6 O 24 host lattice. And the highest quantum efficiency can reach 64.5% in Ba 9 Y 2 Si 6 O 24 :0.024Bi 3+ phosphor. The remarkable spectral overlap between the emission spectra of Bi 3+ ions and the excitation spectra of Eu 3+ ions indicated the exist of energy transfer from Bi 3+ to Eu 3+ . The efficient energy transfer from Bi 3+ to Eu 3+ has been investigated in detail and resulted in that tunable and white-light emission can be obtained by modulating Eu 3+ doping concentration. White emission can be realized with the CIE coordinates of (0.357, 0.345) and quantum efficiency of 57.6% for Ba 9 Y 2 Si 6 O 24 :0.024Bi 3+ ,0.02Eu 3+ . The above results demonstrate that Ba 9 Y 2 Si 6 O 24 :Bi 3+ ,Eu 3+ may be a potential candidate for ultraviolet (UV) driven white light-emitting diodes (w-LEDs).
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高影响因子
Separation Science Plus
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2018
·Vol. 1
·期 5
·367-373
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IF 0
Xuemei Wang,Huan Wang,Pengfei Huang,Xiaomin Ma,Xinzhen Du,Xiaoquan Lu
A specific, precise and accurate high-performance liquid chromatography method with ultraviolet detection was established for the simultaneous determination of eight insecticides in fruit samples. Samples were extracted with acetone and cleaned using the quick, easy, cheap, effective, rugged, and safe technique. Under the optimized conditions, wide linearity ranges (5.0–2000 μg kg −1 ) were obtained for the eight insecticides and the correlation coefficients ( r ) ranged from 0.9985 to 0.9994. The limit of detection and limit of quantification were 0.27–1.85 and 0.90–6.18 μg kg −1 , respectively, and acceptable reproducibility (RSD < 6.6% for intra-day, < 9.2% for inter-day) were achieved. The recovery rates for all insecticides at two spiked levels of 20 and 50 μg kg −1 in fruits samples ranged from 85.9 to 110.4%, and the relative standard deviations were in the range of 3.3–8.9%. The results demonstrated clearly that the approach developed provides reliable, simple, rapid and environmentally friendly quantification and identification of eight insecticides in fruits. These results not only gave insights about the insecticides but also contributed to environmental protection and food safety.
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CHEMICAL ENGINEERING JOURNAL
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2018
·
IF 6.735
Xiao-Fei Wang,Gui-Gen Wang,Jia-Bing Li,Zheng Liu,You-Xiao Chen,Long-Fei Liu,Jie-Cai Han
Herein we first report new chlorine-doped graphene quantum dots (Cl-GQDs) that can be used in solid-state white-light-emitting diodes (WLEDs). The Cl-GQDs with a mean size of 1.53 nm are obtained by one-step hydrothermal method using β-cyclodextrin and hydrochloric acid as the source materials. The PL emission spectra of the Cl-GQDs show an excitation-wavelength-dependent behavior in the range from 300 to 380 nm excitation. Under UV irradiation, the Cl-GQDs can direct emit white light. Given that they are worth using in light-conversion, Cl-GQDs embedded solid composite film (Cl-ESCF), based on silicon resin as host material, is successfully fabricated by solution-processing approach. The freestanding Cl-ESCF has high transparency and flexibility, excellent photostability and temperature resistance, and retains its optical properties in the solid state. In order to realize its potential, the Cl-ESCF converted remote UV-pumped WLED is demonstrated. The results verify that the Cl-GQDs can be homogeneously dispersed within solid matrix without obvious aggregation so that a uniform and defect-free natural white light can be obtained. In addition, our WLED possesses favorable white-light characters with the CIE of (0.33, 0.34), moderate CCT of 5653 K, and high CRI of 87.6, as well as good color and LED stability. This single-phase rare-earth-free white-luminescent Cl-GQDs may be not only expected to prevent the drawbacks of multicolor phosphors, thereby generating high-quality white emission, but also identified to be a green alternative for conventional emitters.
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高影响因子
Journal of Materials Chemistry C
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2018
·Vol. 6
·期 47
·12879-12887
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IF 5.976
Zhuang Li,Fei Liang,Yangwu Guo,Zheshuai Lin,Jiyong Yao,Guochun Zhang,Wenlong Yin,Yicheng Wu,Chuangtian Chen
Demands for UV birefringent materials are growing dramatically owing to the rapid development of ultraviolet technology. Here, a new family of UV birefringent materials, Ba2Mg(C3N3O3)2 (BMCY) and Ba2Ca(C3N3O3)2 (BCCY), have been successfully discovered. It is the first time that the excellent birefringent properties of cyanurates have been studied. These materials exhibit an extremely large birefringence (Δn = 0.728–0.351 and 0.771–0.346 from 230 nm to 800 nm for BMCY and BCCY, respectively), much larger than that of the commercial UV birefringent crystal α-BaB2O4 (α-BBO) (Δn = 0.12@532 nm). Our study indicates that the impressive optical properties of BMCY and BCCY stem from the strengthened optical anisotropy of the planar (C3N3O3)3− group compared with the isoelectronic (B3O6)3− group. Besides, its congruent-melting properties make it feasible to grow a bulk crystal by the Bridgman–Stockbarger technique. The extraordinary properties of BMCY and BCCY may shed light on a new path to explore birefringent materials for practical application.
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高影响因子
Analytical Methods
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2013
·Vol. 5
·期 8
·1991-1995
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IF 1.855
Juan Du,Zhining Xia
Spherical gold nanoparticles (GNPs), with an average diameter of 13 nm, were synthesized and their catalytic activity was measured by a spectroscopic method. The GNPs were synthesized by a microwave-assisted heating method under reflux, using trisodium citrate as the reducing agent. UV spectra and transmission electron microscopic (TEM) analysis were used to characterize the GNPs. The as-prepared GNP solutions were then successfully used as the catalyst in the borohydride reduction of nitrophenols. The reaction could be monitored by the time-dependent UV spectra. The reduction of nitrophenols followed a pseudo-first-order kinetic model and the apparent rate of different isomeric nitrophenols followed the order: m-nitrophenol > p-nitrophenol > o-nitrophenol.
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高影响因子
PROGRESS IN ORGANIC COATINGS
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2013
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IF 1.848
Yugang Huang,Laixing Pang,Hongliang Wang,Rong Zhong,Zhaohua Zeng,Jianwen Yang
UV-curable tung oil based resins of GMA-PCDMAT and GMA-ICDMAT were synthesized via Diels–Alder reaction with maleic anhydride (MA), subsequent nonisocyanate polyurethane (NIPU) reaction with piperazine-1,4-dicarboxylic acid bis-(2-hydroxy-ethyl) ester (PCD) or isophoronediamine-1,4-dicarboxylic acid bis-(2-hydroxy-ethyl) ester (ICD) and acrylated modification with glycidyl methacrylate (GMA). The final chemical structures of GMA-PCDMAT and GMA-ICDMAT depend on the feeding ratio of MA, tung oil, PCD (or ICD) and GMA. Results of 1 H NMR and FTIR revealed that the targeted tung oil-based resins were successfully obtained. All the obtained resins had broad molecular weight distributions. UV-curing kinetic and thermal properties were respectively revealed by photo-DSC, DSC and TG. Higher concentration of C C bonds led to faster curing rate but lower final conversion of C C bonds. All the cured films had two glass transitions, one in the range of 8–10 °C and another in the range of 46–48 °C. All the cured films possessed excellent thermal stability, and the start temperature of decomposition ( T sta ) was as high as 350 °C, implying that they can be used for UV coatings for the substrates with high-temperature resistance. The introduction of structure of NIPU is helpful to enhance adhesion of the cured films with substrates.
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高影响因子
Nano Life
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2015
·
IF 0
Qiong Yi,Ling Li,Wei Hong,Lu Fan
A composite of chromium (III) terephthalate metal-organic framework and graphene oxide (MIL-101/GO) coated stir bar was prepared by sol–gel technique for the first time and was employed for stir bar sorptive extraction (SBSE) of trace azo dyes amaranth, sunset yellow and carmine from water samples followed by UV–Vis spectrophotometric detection. A MIL-101/GO coating was first created on the glass bar surface. MIL-101/GO and MIL-101/GO coated stir bars were characterized. The enrichment factors of azo dyes by SBSE have been investigated in detail, and the optimized experimental parameters were obtained. Under the optimal conditions, a method for determination of trace amount of azo dyes was setup, and the detection limits of amaranth, sunset yellow and carmine were 2.3 ng/mL, 1.7 ng/mL and 1.6 ng/mL. The proposed method was successfully applied for the analysis of the three azo dyes in water samples.
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OPTICS EXPRESS
·
2015
·Vol. 23
·期 13
·17487-17510
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IF 3.488
Dibo Hou,Jian Zhang,Zheling Yang,Shu Liu,Pingjie Huang,Guangxin Zhang
The issue of distribution water quality security ensuring is recently attracting global attention due to the potential threat from harmful contaminants. The real-time monitoring based on ultraviolet optical sensors is a promising technique. This method is of reagent-free, low maintenance cost, rapid analysis and wide cover range. However, the ultraviolet absorption spectra are of large size and easily interfered. While within the on-site application, there is almost no prior knowledge like spectral characteristics of potential contaminants before determined. Meanwhile, the concept of normal water quality is also varying due to the operating condition. In this paper, a procedure based on multivariate statistical analysis is proposed to detect distribution water quality anomaly based on ultraviolet optical sensors. Firstly, the principal component analysis is employed to capture the main variety features from the spectral matrix and reduce the dimensionality. A new statistical variable is then constructed and used for evaluating the local outlying degree according to the chi-square distribution in the principal component subspace. The possibility of anomaly of the latest observation is calculated by the accumulation of the outlying degrees from the adjacent previous observations. To develop a more reliable anomaly detection procedure, several key parameters are discussed. By utilizing the proposed methods, the distribution water quality anomalies and the optical abnormal changes can be detected. The contaminants intrusion experiment is conducted in a pilot-scale distribution system by injecting phenol solution. The effectiveness of the proposed procedure is finally testified using the experimental spectral data.
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PubMed
高影响因子
Food Analytical Methods
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2015
·Vol. 8
·期 10
·2588-2594
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IF 1.956
Jiang Ting-Fu,Chong Lei,Yue Mei-E,Wang Yuan-Hong,Lv Zhi-Hua
In this study, the separation and determination of carbohydrates in food samples were developed by capillary electrophoresis using dynamically coating the capillary with indirect UV detection. The polycationic polymers of hexadimethrine bromide (HDB) were used as electroosmotic flow (EOF) modifier to reverse the EOF. A highly alkaline pH condition was used in order to charge every carbohydrate negatively. Several important parameters influencing buffer concentration, pH, and HDB concentration were optimized. The optimal background electrolyte composed of 20 mmol L −1 sorbic acid, 0.005 % ( w / v ) HDB, and 40 mmol L −1 NaOH at pH 12.2. Under optimal conditions, 32 carbohydrates including mono-, di-, oligosaccharides, and sugar alcohols were separated in less than 12 min. The proposed method provided a good linearity, low limits of detection, and good repeatability of the carbohydrates. This method was then utilized to analyze carbohydrates in food samples. The results indicated that the developed method is an excellent alternative for the carbohydrate routine analysis in the food field.
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高影响因子
PROGRESS IN ORGANIC COATINGS
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2016
·
IF 2.632
Guangxue Chen,Xiaoyuan Guan,Ruixin Xu,Junfei Tian,Minghui He,Wei Shen,Jianwen Yang
In this paper, UV-curable castor oil-based polyfunctional polyurethane acrylate (COME-PUA) was synthesized via photo-click chemistry and isocyanate polyurethane reaction. Facile and highly efficient side-chain functionalization of castor oil (CO) was first achieved via thiol-ene photo-click chemistry with β-mercaptoethanol (ME). 1 H NMR result indicated that almost 100% conversion of double-bond in CO was observed within 10 min, and the average hydroxyl functionality of the obtained polyol COME was about 6. Next, COME was modified by isocyanate polyurethane reaction with hydroxypropyl acrylate (HPA), isophorone diisocyanate (IPDI) and PEG-200 as the chain extender in order to prepare the resin COME-PUA. Results of both 1 H NMR and FTIR revealed that the targeted COME and COME-PUA were successfully synthesized. Furthermore, UV-curing kinetic of COME-PUA was revealed by real-time FTIR, showing a higher UV-curing rate than the common CO-PUA. Finally, some physical properties of curing films were studied.
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高影响因子
RSC Advances
·
2014
·Vol. 4
·期 44
·23036-23042
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IF 3.708
Songqi Ma,Yanhua Jiang,Xiaoqing Liu,Libo Fan,Jin Zhu
The utilization of soybean oil-based UV coatings depends on the introduction of petroleum-based comonomers or crosslink agents. Thus, in this paper, a bio-based crosslink agent (GACA) for UV curable coatings was synthesized from gallic acid and its chemical structure was confirmed by FT IR, 1H NMR and 13C NMR. Crosslinked networks with high biobased content of more than 88% were obtained after co-photopolymerization between acrylated epoxidized soybean oil (AESO) and GACA. The thermal, mechanical and coating properties of these GACA crosslinked AESO networks were investigated and a commonly used crosslink agent triallyl isocyanurate (TAIC) was used as the control. GACA exhibited more functional groups and better copolymerization with AESO than TAIC, resulting in the higher gel content, crosslink density, tensile strength and modulus as well as much better coating properties (reflected by the higher pencil hardness, better wear resistance and adhesion) of GACA crosslinked AESO networks than TAIC crosslinked AESO networks. These results indicated that GACA exhibited great potential to replace petroleum-based crosslink agents such as TAIC, and high-performance soybean oil-based UV-cured coatings with high biobased content could be achieved after introducing GACA.
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高影响因子
危险品化学品经营许可证（带存储）