JOURNAL OF LABELLED COMPOUNDS & RADIOPHARMACEUTICALS
·
2018
·Vol. 61
·期 14
·1043-1047
·
IF 1.423
Wulian Chen,Chaomin Zhao,Xiaojun Deng
An efficient and simple synthetic route of deuterium-labeled 2-quinoxalinecarboxylic acid- d 4 (QCA- d 4 ) and 3-methylquinoxaline-2-carboxylic acid- d 4 (MQCA- d 4 ) is presented with 99.9% and 99.6% isotopic enrichment using aniline- d 5 as labeled starting material. Their chemical structures were confirmed by 1 H NMR, and their isotopic abundance was determined by mass spectrometry analysis.
研究领域:
有机化学
·
药物化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Shijie Wang,Shenghan Zhang,Zhenye Zhang,Yu Tan,Kexin Liang,Xinliang Guo,Xuhui Kong
Nitrogen heterocyclic organics are promising hydrogen storage carriers with the advantage of being capable of large-scale transportation over long distances using existing oil and gas facilities. However, traditional methods for the hydrogenation and dehydrogenation of organic hydrogen carriers usually require high temperature and pressure conditions and external hydrogen supplies, which hinder their large-scale applications, as well as having certain safety risks. In this paper, a reversible electrochemical hydrogen storage system using quinoxaline as a hydrogen carrier was developed with potential for use at room temperature and atmospheric pressure. Experiments revealed that the hydrogenation conversion of quinoxaline reached 95% within 120 min at −0.20 V vs. RHE, and the dehydrogenation conversion of 1,2,3,4-tetrahydroquinoxaline reached 100% within 30 min at 1.30 V vs. RHE. This means that the system achieved quick and efficient reversible hydrogen storage. The Pd/NF dual-function electrode prepared by spontaneous redox reaction still showed high catalytic activity after 8 cycles, indicating its good long-term stability. The proton donor in the electrochemical hydrogenation process of quinoxaline was water, which completely eliminates the safety risk from the use of external hydrogen. This work provides a simple and reliable strategy for efficient hydrogen storage using nitrogen heterocyclic organics.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Mengyuan Lv,Minghao Zhai,Yunlong Zang,Ziyu Zhuang,Xinying Lv,Wanan Cai,Haijun Niu,Tingting Zhou,Wen Wang
With the aim to obtain multifunctional durable electrochromic (EC) devices, we propose an effective strategy by introducing weak electron acceptor segment with suitable bandgap and oxidation potential. A series of quinoxaline-based units polyamides (PAs) (denoted as T 2 BPA-CA, T 2 BPA-OA, T 2 BPA-TP, and T 2 BPA-SA) were prepared from a novel donor–acceptor-donor (D-A-D) type diamine with weak electron acceptor quinoxaline and connected with two methoxyl-substituted donor triphenylamine, 10,13-bis[4-aminophenyl (4-methoxyphenyl) amino]-dibenzo[a,c]phenazine, and four dicarboxylic acids, which are high soluble in various organic solvents and exhibit excellent thermostability. Furthermore, the T 2 BPA-SA thin film exhibits excellent EC performance with outstanding optical contrast (50 %), high coloration efficiency (230 cm 2 C −1 ) and impressive cycle stability (optical contrast remains 80 % over 1400 cycles) in the NIR range. Meanwhile, all of these PAs are served as memristors and exhibit typical nonvolatile ternary memory, realizing an accessible threshold voltage of −0.65 V, a retention time of more than10 4 s and high current switch ratio (10 3.52 :10 2.43 :1). Overall, this work implies the great potential of these PAs in EC displays and memory storage devices.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
ORGANIC ELECTRONICS
·
2019
·
IF 3.495
Yan Zhang,Hongmei Du,Yiming Yin,Yunyun Dong,Jinsheng Zhao,Zhen Xu
Three soluble donor-acceptor (D-A) type copolymers employing benzene (B) as donor, 2-dodecyl-4,7-di(thiophen-2-yl)-2H-benzo [d][1,2,3]triazole (Z) and 2,3-bis((4-(2-octyldodecyl)oxy)phenyl)-quinoxaline (Q) as acceptors were synthesized through chemical polymerization. A variety of characterization methods such as cyclic voltammetry , UV–vis spectroscopy, colorimetry and thermogravimetric analysis were executed to detect the electrochromic properties of polymers. All the polymers displayed multicolor in the redox process with medium band gaps, and different molar ratio of B/Z/Q allowed them to cover diverse color changes, containing orange-red/brown-yellow/cyan/green (PBZQ-1), orange-red/yellow/light grass green (PBZQ-2), and red/black/grey-blue (PBZQ-3). The multichromism of the polymers involved RGB and black colors. Meanwhile, with the increase of Z unit ratio and the decrease of Q unit ratio, the polymer demonstrated the reduced onset oxidation potential and optical band gap, as well as the different kinetic parameters . Moreover, the three polymers exhibited good solubility, desirable thermal stability, relatively large optical contrast and high coloration efficiency. The above positive results implied that these copolymers were expected to be the credible candidates for the electrochromic devices with commercial values.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Zhaohua He,Xudong Chen,Haifeng Yu,Yanting Du,Meng Gao,Shuhong Wang,Cheng Wang
Quinoxaline-based polymer materials have been used in various optoelectronic devices, but their utilization in polymer-based memory devices is rarely explored. Herein, a class of solution-processable, quinoxaline-based donor–acceptor conjugated polymers were synthesized and applied to fabricate memristors with the sandwich structure of indium-tin-oxide/active layer/aluminum. The quinoxaline was decorated by phenanthrene or acenaphthene to serve as the acceptor in these conjugated polymers. Incorporation of the phenanthrene or acenaphthene moiety in the quinoxaline structure was found to provide an extra charge trap site, bringing about interesting ternary switch behavior. Notably, these ternary memristors exhibit promising device performance, realizing the threshold voltages of −0.64 V and ON/OFF ratios exceeding 10 4 . And they can still show ternary switch behavior after 10 3 cycles with a retention time are over 10 4 s. This work demonstrates the potential of quinoxaline-based materials for ternary memory applications and useful strategies for designing ternary storage materials.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2024
·
IF 5.8
Jingwei Jiang,Yunlong Sun,Zhipeng Wang
With the rapid growth of 5G communication technology, low-dielectric materials can decrease the loss of the signal during transmission. Hence, there is an urgent need to develop high-performance materials with low dielectric constant (D k ) and dielectric loss (D f ) at high frequency. In this study, we propose a strategy that combines bulk rigid quinoxaline structure and low polarizability trifluoromethyl group to prepare poly (aryl ether)s (PAEs) with low D k and D f at high frequencies. The effect of methyl substituents on the properties of PAEs was focuses on investigated. Accordingly, three difluoro-monomers containing quinoxaline structures were designed and prepared and novel quinoxaline-based PAEs with different numbers of methyl substituents were synthesized by nucleophilic condensation reactions with the bisphenol monomer hexafluorobisphenol A (BP6F). Test results that the resultant PAEs exhibited excellent thermal and solubility properties, with 5 % thermal decomposition temperatures ( T d5% ) in the range of 500−515 °C and glass transition temperatures ( T g ) reaching 225 °C. Furthermore, these PAE films show outstanding optical transparency, with cut-off wavelengths of 398−400 nm and above 87 % transmission at 800 nm. Most importantly, the novel PAE films possess ultra-low D k and D f , with the lowest values reaching 2.45 and 0.0024 at 10 GHz and maintain low water absorption (0.53–0.63 %). The excellent properties of novel quinoxaline-based PAEs provide its application potential in the field of high-frequency communications.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Green Energy & Environment
·
2020
·
IF 6.395
Jiaqi Wu,Lei Zhang,Jinxing Long,Qiang Zeng,Biaolin Yin,Xuehui Li
Ionic liquids (ILs) have attracted increasing attention since last few decades due to their high molecular design abilities and wide applications in different fields. In this study, four novel fluorescent isoquinolino [2,1-a]quinoxalin-5-ium ILs were designed and synthesized via a two-step process including a simple dual Schiff's base formation and a subsequent [RhCp∗Cl 2 ] 2 -catalyzed oxidative C–H activation/annulation reaction. The as-synthesized ILs were extensively characterized using FT-IR, 1 H-NMR, 13 C-NMR, 19 F-NMR, HSQC-NMR, HMBC-NMR and HR-MS. Their photophysical properties were determined by steady-state fluorescence spectroscopy. The results demonstrate that all these ILs showed dual or triple emissions, large stokes shift (90 nm) and mechanochromic behaviors. Basing on solvatochromism and titration experiments, it is thought that the emission bands of the ILs are raised from their local excited states, charge transfer states or excited state proton transfer of cations, while the substitute effect of these quinoxaline derived ILs on their stokes shifts is negligible.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2010
·
IF 3.792
Xinbing Chen,Pei Chen,Zhongwei An,Kangcheng Chen,Kenichi Okamoto
A series of crosslinkable sulfonated poly(arylene ether ketone)s (SPAEKs) were synthesized by copolymerization of 4,4′-biphenol with 2,6-difluorobenzil and 5,5′-carbonyl-bis(2-fluorobenzene-sulfonate). A facile crosslinking method was successfully developed, based on the cyclocondensation reaction of benzil moieties in polymer chain with 3,3′-diaminobenzidine to form quinoxaline groups acting as covalent and acid–base ionic crosslinking. The uncrosslinked and crosslinked SPAEK membranes showed high mechanical properties and the isotropic membrane swelling, while the later became insoluble in tested polar aprotic solvents. The crosslinking significantly improved the membrane performance, i.e., the crosslinked membranes had the lower membrane dimensional change, lower methanol permeability and higher oxidative stability than the corresponding precursor membranes, with keeping the reasonably high proton conductivity. The crosslinked membrane ( C-B4 ) with an ion exchange capacity of 2.02 mequiv. g −1 showed a reasonably high proton conductivity of 111 mS cm −1 with a low water uptake of 42 wt% at 80 °C. C-B4 exhibited a low methanol permeability of 0.55 × 10 −6 cm 2 s −1 for 32 wt% methanol solution at 25 °C. The crosslinked SPAEK membranes have potential for PEFC and DMFC applications.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
PEST MANAGEMENT SCIENCE
·
2021
·Vol. 78
·期 3
·938-946
·
IF 4.845
Wei Hu,Shuang Gao,Li-Xia Zhao,Ke-Liang Guo,Jia-Yu Wang,Ying-Chao Gao,Xin-Xin Shao,Ying Fu,Fei Ye
BACKGROUND 4-Hydroxyphenyl pyruvate dioxygenase (EC 1.13.11.27, HPPD) is one of the important target enzymes used to address the issue of weed control. HPPD-inhibiting herbicides can reduce the carotenoid content in plants and hinder photosynthesis, eventually causing albinism and death. Exploring novel HPPD-inhibiting herbicides is a significant direction in pesticide research. In the process of exploring new high-efficiency HPPD inhibitors, a series of novel quinoxaline derivatives were designed and synthesized using an active fragment splicing strategy. RESULTS The title compounds were unambiguously characterized by infrared, 1 H NMR, 13 C NMR, and high-resolution mass spectroscopy. The results of the in vitro tests indicated that the majority of the title compounds showed potent inhibition of Arabidopsis thaliana HPPD ( At HPPD). Preliminary bioevaluation results revealed that a number of novel compounds displayed better or excellent herbicidal activity against broadleaf and monocotyledonous weeds. Compound III-5 showed herbicidal effects comparable to those of mesotrione at a rate of 150 g of active ingredient (ai)/ha for post-emergence application. The results of molecular dynamics verified that compound III-5 had a more stable protein-binding ability. Molecular docking results showed that compound III-5 and mesotrione shared homologous interplay with the surrounding residues. In addition, the enlarged aromatic ring system adds more force, and the hydrogen bond formed can enhance the synergy with π–π stacking. CONCLUSIONS The present work indicates that compound III-5 may be a potential lead structure for the development of new HPPD inhibitors.
研究领域:
植物保护
·
农药化学
·
计算生物学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2014
·Vol. 2
·期 38
·8047-8053
·
IF 0
Tong Hu,Liangliang Han,Manjun Xiao,Xichang Bao,Ting Wang,Mingliang Sun,Renqiang Yang
Copolymers based on benzodithiophene and quinoxaline, represented by 4,8-bis(5-(3,4,5-tris(octyloxy)phenyl)thiophen-2-yl)benzo[1,2-b:4,5-b′]dithiophene (TOBDT) and 2,3-diphenyl-5,8-di(thiophen-2-yl)quinoxaline (TQ1) or 10,13-bis(4-(2-ethylhexyl)thiophen-2-yl)dibenzo[a,c]phenazine (TQ2), were synthesized via a Stille coupling reaction. By increasing the conjugation in the TQ2 unit, the polymer based on TQ2 showed a narrower band gap (Eg), a lower highest occupied molecular orbital energy level and enhanced interchain π–π interactions. Polymer solar cells based on TQ2 showed a simultaneous enhancement of the open-circuit voltage (Voc), short-circuit current density (Jsc) and fill factor (FF) compared with polymer solar cells based on the TQ1 polymer. A good power conversion efficiency of 4.24% was achieved by solar cells based on the TQ2 polymer and [6,6]-phenyl-C71-butyric acid methyl ester composite. These preliminary results indicate that increasing the acceptor unit (quinoxaline) conjugation is an effective way of improving the performance of polymer solar cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
Polymers
·
2022
·Vol. 14
·期 8
·1554
·
IF 4.967
Yiping Guo,Zeyang Li,Mengzhen Sha,Ping Deng,Xinyu Lin,Jun Li,Liang Zhang,Hang Yin,Hongbing Zhan
A simple wide-bandgap conjugated polymer based on indoloquinoxaline unit (PIQ) has been newly designed and synthesized via cheap and commercially available starting materials. The basic physicochemical properties of thePIQhave been investigated.PIQpossesses a broad and strong absorption band in the wavelength range of 400~660 nm with a bandgap of 1.80 eV and lower-lying highest occupied molecular orbital energy level of −5.58 eV. Polymer solar cells based onPIQand popular acceptor Y6 blend display a preliminarily optimized power conversion efficiency of 6.4%. The results demonstrate indoloquinoxaline is a promising building unit for designing polymer donor materials for polymer solar cells.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2015
·Vol. 6
·期 12
·2337-2347
·
IF 5.52
Xiaopeng Xu,Kai Li,Zuojia Li,Ying Li,Zhenguo Wang,Qiang Peng
Fluorinated quinoxaline units are attractive acceptor blocks for building low band gap photovoltaic polymers. In this contribution, two novel fluorinated quinoxaline-based copolymers, PCPDTBFQ and PDTSBFQ, have been successfully synthesized by combination of cyclopentadithiophene (CPDT) or dithienosilole (DTS) donor blocks in the polymeric backbones. The bridging atom effect shows a great influence on the absorption properties, energy level, carrier mobility as well as photovoltaic performance. PDTSBFQ with Si bridging atoms shows a little blue-shift in the UV-vis absorption, and a little larger band gap than PCPDTBFQ. However, PDTSBFQ shows a stronger aggregation even in the solution state. Compared with carbon, silica atoms afforded PDTSBFQ with a lower-lying HOMO level, suggesting a high Voc for polymer solar cells (PSCs). PDTSBFQ also exhibits better crystallinity and molecular ordering properties than PCPDTBFQ from the XRD study. The hole-only device based on PDTSBFQ exhibited a higher hole mobility of 1.5 × 10−5 cm2 V−1 s−1 than that of 4.1 × 10−6 cm2 V−1 s−1 for PCPDTBFQ. Conventional PSCs were fabricated to investigate the bridging atom effect on the photovoltaic properties of these two copolymers. Different interfacial layers (IFLs) of Ca and PFN had been tried to optimize the performance of the fabricated PSCs. When using a Ca/Al top electrode, PCPDTBFQ and PDTSBFQ devices showed PCEs of 2.16% and 4.43%, respectively. The better performance of the PDTSBFQ device can be attributed to the improvements in its Voc, Jsc and FF values just by choosing silica bridging atoms. After replacing the Ca/Al with a PFN/Al cathode, the performance of both PCPDTBFQ and PDTSBFQ devices was enhanced largely. The PDTSBFQ device achieved the highest PCE of 5.92% with a Voc of 0.77 V, a Jsc of 12.25 mA cm−2 and an FF of 0.63. The primary results gave a simple but efficient strategy to design high performance dithiophene-quinoxaline polymer donors for organic solar cell applications.
研究领域:
材料科学
·
有机光电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）