ORGANIC ELECTRONICS
·
2021
·
IF 3.721
Yijia Zhou,Xiaofeng Zhao,Yingna Zhang,Feng Dou,Shuhong Wang,Cheng Wang
The poly[2,7-9-(9-heptadecanyl)-9H-carbazole-co-benzo[4,5] imidazole[2,1-a]isoindol-11-one] (PCz-O) was synthesized by Suzuki coupling reaction, which structure was verified by FT-IR, 1 H NMR and 13 C NMR. The spin coating method was used to prepare RRAM devices based on PCz-O: ZrO 2 nanoparticle active layer, and the devices exhibited ternary switching. Through a series of performance tests, both pure polymer device and composited with ZrO 2 NPs devices had ternary storage characteristics. Among them, the content of composited with 8 wt% ZrO 2 showed the most excellent ternary storage characteristics. The ON/OFF current ratio was 2.60 × 10 4 , and the threshold voltage V th1 / V th2 was −0.60 V/-1.00 V. The current is stable for 10000 s in both ON/OFF states. After 3300 times of reading, the switch state current of the devices had slight variation. In addition, the switching mechanism of the device was also discussed. Through carefully testing and analyzing, the devices had good stability and durability, and had potential application value in terms of data storage.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
ACS Applied Energy Materials
·
2024
·
IF 5.4
Ning Xie,Tao Wang,Haowei Kang,Yiting Liu,Xinli Li,Qiang Weng,Xingming Ning,Pei Chen,Xinbing Chen,Zhongwei An
High-performance anion exchange membranes (AEMs) have garnered increasing attention in recent years. However, commercial progress of the AEM for fuel cells is still hindered by its low ionic conductivity and inadequate alkaline stability. In this study, we propose the incorporation of a hydrophobic rigid-flexible coupled side chain into a polycarbazolyl AEM as an innovative approach to enhance both the conductivity and stability. The results demonstrate that the AEMs with hydrophobic rigid-flexible coupled side chains exhibit superior conductivity and stability compared with those without (PQMC-0). For example, the ion exchange capacity of PQMC-10 is reduced by 11% than PQMC-0, but its conductivity is enhanced by 14%, dimensional change is decreased by almost half, and oxidative stability is increased by more than four times. Improved conductivity of the AEMs can be attributed to the presence of hydrophobic rigid-flexible coupled side chains, making it easier for AEM to construct microphase separation to facilitate ion transport. Furthermore, the introduction of hydrophobic side chains reduces water absorption of the membrane, thereby enhancing its dimensional stability while minimizing the intake of free radicals or hydroxide ions present in water. Consequently, this modification significantly improves the oxidative and alkaline stability as well. Finally, the PQMC-10 shows a maximum power density of 649 mW cm–2 in a single fuel cell, which is three times bigger than that of PQMC-0, indicating a promising application in the field of fuel cells.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2015
·Vol. 38
·期 9
·1570-1576
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IF 2.737
Yuanyuan Feng,Faqiong Zhao,Baizhao Zeng
A polycarbazole film was electrodeposited on a stainless-steel wire from a solution of N , N -dimethylformamide/propylene carbonate (1:9 v/v) containing 0.10 M carbazole and 0.10 M tetrabutylammonium perchlorate. The obtained polycarbazole fiber was immersed into an ionic liquid (1-hydroxyethyl-3-methyl imidazolium bis[(trifluoromethyl)sulfonyl]imide) solution (in dimethylsulfoxide) for 30 min, followed by drying under an infrared lamp. The resulting polycarbazole/ionic liquid fiber was applied to the headspace solid-phase microextraction and determination of aromatic esters by coupling with gas chromatography and flame ionization detection. Under the optimized conditions, the limits of detection were below 61 ng/L (S/N = 3) and the linear ranges were 0.061−500 μg/L with correlation coefficients above 0.9876. The relative standard deviations were below 4.8% ( n = 5) for a single fiber, and below 9.9% for multi-fiber ( n = 4). This fiber also exhibited good stability. It could be used for more than 160 times of headspace solid-phase microextraction and could withstand a high temperature up to 350°C.
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
TALANTA
·
2015
·
IF 3.545
Yuanyuan Feng,Mian Wu,Faqiong Zhao,Baizhao Zeng
A novel polycarbazole (PCz)–ionic liquid (IL, i.e. 1-hydroxyethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide, [HOEMIm][NTf 2 ]) composite coating (PCz-IL) was fabricated by electrodeposition. The IL could facilitate the electrodeposition of poor-conductive PCz and a more porous coating was obtained. The composite coating exhibited enhanced extraction capacity for some environmental pollutants (i.e. o-chlorotoluene, p-bromotoluene, o-nitrotoluene, m-nitrotoluene, p-nitrotoluene), as they could interact through π-π and hydrophobic interactions. Compared with [HOEMIm][NTf 2 ] coated fiber, some other PCz-IL fibers (here IL=1-hydroxyethyl-3-methylimidazolium hexafluorophosphate and 1-methyl-3-octylimidazolium hexafluorophosphate) and commercial fibers (i.e. polydimethylsiloxane and polyacrylate), the PCz-IL fiber showed better performance. It was used for the determination of the environmental pollutants by coupling with gas chromatography, the limits of detection were 47.8–65.9 ng L −1 under the optimized conditions and the linear ranges were 0.1–500 μg L −1 with correlation coefficients above 0.9947 for different compounds. The relative standard deviations (RSDs) were 3.4–4.6% for five successive extractions with single fiber, and the RSDs for inter-fiber were 6.5–10.4% ( n =5). The fiber was successfully applied to the detection of real samples and the recoveries for standards added were 88.6–108.8% with RSDs below 9.7%.
研究领域:
分析化学
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环境科学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Ning Xie,Jinchao Han,Haowei Kang,Yiting Liu,Qiang Weng,Xingming Ning,Pei Chen,Xinbing Chen,Zhongwei An
Anion exchange membranes (AEMs) are crucial components of anion exchange membrane fuel cells (AEMFCs), and the development of highly efficient and stable AEMs is fundamental for advancing the practicality of AEMFCs. In this study, we propose the concept of “combining rigidity and flexibility” to design a series of poly(carbazole)-based AEMs with unique dual side chains. One side chain is a flexible dialkoxy chain, while the other consists of a rigid aromatic structure attached to two flexible alkyl chains. The resulting AEMs exhibit a remarkably high ionic conductivity, ranging from 120.2 to 175.7 mS cm–1 at 80 °C, along with an ion exchange capacity of 1.64–2.19 mequiv g–1. These properties are attributed to significant microphase separation facilitated by the strong interaction between the dual side chains. Furthermore, these AEMs demonstrated excellent alkaline stability. Even after being immersed in NaOH solution for 1080 h, their conductivity remains above 92%. This exceptional stability against hydroxide ions is attributed to the large electrostatic potential of the dialkoxy side chain, as verified by density functional theory calculations. Importantly, when incorporated into a hydrogen–oxygen fuel cell, the AEMs enable the fuel cell to achieve a large power density of 605 mW cm–2 at 70% relative humidity. This remarkable performance underscores their potential application prospects in the field of alkaline fuel cells. As a result, our findings contribute to the ongoing advancement of the AEMFC technology.
研究领域:
材料科学
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能源技术
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Wenli Ma,Lin Tian,Qingzhi Zhang,Lijian Shangguan,Fanghui Wang,Hong Zhu
To overcome the imbalance between high ionic conductivity, dimensional stability and strong alkali resistance in anion exchange membranes (AEMs), this work discarded the traditional polymer structure with cationic main chains, while prepared n-DTMA-PHCZBDO AEMs with different alkyl chain lengths by combining hydrophilic bi-cationic side chains and hydrophobic alkyl long side chains. The performance test results showed that membrane 6-DTMA-PHCZBDO has high ionic conductivity (169.2 mS cm -1 ), good dimensional stability (WU 140.3 %, SR 30.1 %) and excellent mechanical properties (55.3 MPa). Particularly, the ionic conductivity and tensile strength degradation rate of membrane 6-DTMA-PHCZBDO were less than 10 % after stabilization in 2 M NaOH at 80 °C for 2000 h, showing outstanding alkali resistance. Besides, It not only exhibited low resistance (R ohm 0.134 Ω cm 2 and R ct 0.035 Ω cm 2 ), high current density at 40 °C (1.00 A cm -2 ), 50 °C (1.83 A cm -2 ) and 60 °C (2.40 A cm -2 ) in 2.2V, but also showed good durability (degradation rate 1.71 mV h -1 , at 1000 mA cm -2 for 60 h) in anion exchange membrane water electrolysis (AEMWEs). Importantly, membrane 6-DTMA-PHCZBDO could be well realized for dual application of AEMWEs and fuel cells, which also had good H 2 -O 2 fuel cell power density (490.93 mW cm -2 ). Therefore, the hydrophilic and hydrophobic dual side linking branches can enhance the comprehensive performance of AEMs and can facilitate the application of it in AEMWEs and H 2 -O 2 fuel cell.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2023
·
IF 3.4
You Tao,Tian-Xiong Wang,Xuesong Ding,Bao-Hang Han
The scopes of synthesis methods of porous polycarbazole materials are still under continuous developments because the polycarbazole materials with high stability and excellent porosity are suitable for various advanced applications. Here, ionothermal synthesis method for preparing porous polycarbazole materials is reported for the first time, by which a series of polycarbazole materials with good porosity and high yield are synthesized. Thereinto, the ferric chloride plays the roles of catalyst and molten solvent for preparing porous polycarbazole materials. The transformation of the pore structure due to slight carbonization during the process of ionothermal synthesis shows profound impacts on application performances. As intercomparison among these polymers, some porous polycarbazole materials with the predominant micropores possess a good performance of carbon dioxide uptake, others with micro-mesopore structures show a high capacity of electrochemical energy storage. This simple and practicable method provides a pathway for synthesizing novel porous polycarbazole materials and similar porous organic polymers. Graphical
研究领域:
材料科学
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环境科学
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能源科学
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产品关联
DOI
高影响因子
POLYMER INTERNATIONAL
·
2021
·Vol. 70
·期 11
·1612-1620
·
IF 2.99
Kuan Liu,Yuhan Wei,Jinyao Xu,Lingfei Qiu,Shaping Hu,Jiayi Wan,Juhua Feng
A novel conjugated polymer PFCZ-IM containing 2-(thiophen-2-yl)-1H-benzo[d]imidazole units was synthesized and characterized. The basic photophysical properties of the polymer and its fluorescence recognition behaviors toward metal ions and amino acids were investigated. In the study of the response of metal ions, PFCZ-IM had high sensitivity to Fe 3+ , Ag + and Cu 2+ , which significantly quenched the fluorescence of the polymer. The binding of the 2-(thiophen-2-yl)-1H-benzo[d]imidazole moiety to Cu 2+ was investigated by density functional theory calculation. Interestingly, [PFCZ-IM-Cu 2+ ] also exhibited outstanding characteristics of fluorescence ‘turn on’ in the presence of cysteine (Cys), as the interaction between Cu 2+ and Cys caused the polymer to dissociate from the complex. In particular, addition of 30 μmol L –1 of Cys can increase the Cu 2+ -quenching fluorescence of PFCZ-IM by 34.8 times with short response time, demonstrating that [PFCZ-IM-Cu 2+ ] has tremendous potential in the actual detection of Cys. This polymer is expected to be utilized for dual fluorescence detection of specific metal ions and Cys. © 2021 Society of Industrial Chemistry.
研究领域:
材料科学
·
分析化学
·
生物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF SEPARATION SCIENCE
·
2014
·Vol. 37
·期 7
·861-867
·
IF 2.594
Meng Wang,Fa-Qiong Zhao,Bai-Zhao Zeng
A novel polycarbazole coating was prepared by cyclic voltammetry on a platinum wire. The solution for electropolymerization contained N , N -dimethylformamide, propylene carbonate (v/v = 1:9), 0.10 M carbazole and 0.10 M tetrabutylammonium perchlorate; the cyclic scan potential range was 0.8–2.0 V (versus Ag/AgCl). The resulting polycarbazole coating showed a porous structure and had a large specific surface area. When it was used for the headspace solid-phase microextraction of chlorobenzenes (i.e. chlorobenzene, 2-chlorotoluene, 1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,2,4-trichlorobenzene) followed by GC analysis, it presented excellent analytical performance. Under the optimized conditions the linear ranges were 0.25–250 μg/L with correlation coefficients >0.985, and the low detection limits were 15–61 ng/L (S/N = 3) for different chlorobenzenes. The RSDs were 2.4–4.9% for five successive measurements with a single fiber, and for fiber-to-fiber they were 6.3–13.1% ( n = 5). Furthermore, the polycarbazole coating displayed good thermal stability (>350°C) and durability (more than 250 times). The proposed method was successfully applied to the extraction and determination of chlorobenzenes in waste water and lake water, and the recoveries for standards added were 86–114% for different analytes.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Catalysis
·
2018
·
IF 11.384
Hai-Peng Liang,Qi Chen,Bao-Hang Han
Photoredox catalysis has aroused great interest from chemists, as it offers a powerful tool for organic synthesis. Cationic polycarbazole networks (CPOP-28 and CPOP-29) were prepared via simple oxidative coupling reaction and applied as heterogeneous photocatalysts for a wide range of oxidative organic transformations, including oxidation of sulfides, hydroxylation of arylboronic acids, and cross-dehydrogenative coupling reactions, in the presence of visible light and air. Remarkably, photocatalytic activities are enhanced by ingenious introduction of trifluoromethyl groups to the polymeric network CPOP-29. The effects of the trifluoromethyl group on photocatalytic activities were elucidated in terms of photophysical and electrochemical properties. The appealing photocatalytic performance of the trifluoromethylated polymer is ascribed to superior light-absorption ability, longer fluorescence lifetime, and stronger oxidative capability. In addition, the photocatalysts showed good recyclability and could be reused after a simple separation workup.
研究领域:
有机化学
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材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
THIN SOLID FILMS
·
2022
·
IF 2.358
Yingna Zhang,Xiaofeng Zhao,Meng Gao,Zhaohua He,Jiangshan Chen,Shuhong Wang,Cheng Wang
In this paper, the donor-acceptor copolymer poly[2,7–9- (heptadecan-9-yl)-9H-carbazole-co-12H-benzo[5,6]isoindolo[2,1- a ]benzimidazole-12-one] (PCz-BI) was synthesized by Suzuki reaction. Devices based on PCz-BI and titanium dioxide (TiO 2 ) nanoparticles composite as the active layer were prepared by a spin coating method and showed ternary resistance switching storage properties. It was shown that the addition of metal oxide nanoparticles improves memory storage performances. The optimum TiO 2 content was 6 wt% and this device had the lowest SET voltage of -0.5 V and the best switching current ratio of 1:10 1.6 :10 4.8 . Moreover, the developed device proved as highly stable during 10 3 cycles. The conductivity and the structural basis for the storage mechanism were studied using electrochemical measurements, ultraviolet-visible spectroscopy, and quantum chemical calculations.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Yuanlong Wu,Jiaran Song,Tianxiang Zhao,Yunji Xie,Di Liu,Le Wang,Genyu Wei,Haidong Ma,Zhe Wang
In recent years, advancements in anion exchange membranes (AEMs) have notably enhanced the overall performance of anion exchange membrane fuel cells (AEMFCs). However, issues like limited alkali stability and low ionic conductivity of AEMs have become apparent. In this study, focusing on molecular design, a series of polycarbazole-based AEMs with flexible side chains, named PCP- n (where ‘ n ’ denotes the molar ratio of the newly synthesized monomer BHC in carbazole derivatives), were developed. The integration of long flexible side chains fosters chain movement and the clustering of piperidine cations, leading to distinct hydrophilic/hydrophobic nanoscale phase separation within the PCP- n membranes. Moreover, the PCP- n membranes demonstrate effective water management capabilities, with the PCP-90 membrane displaying a 32 % water uptake and an in-plane swelling ratio below 20 % at 80 °C. The introduction of an ether-free main chain based on carbazole derivatives along with the highly stable piperidine cationic group endows the PCP- n membranes with exceptional alkali resistance. Following a 1500-h immersion in 2 M KOH at 80 °C, the PCP-90 membrane successfully retains 79.92 % of its original ionic conductivity . Given its substantial thermal stability and mechanical strength , the PCP-90 membrane underwent testing in membrane electrode assembly and single-cell performance, achieving a notable peak power density of 275.64 mW cm −2 and an open-circuit voltage of 0.98 V. Overall, the impressive comprehensive performance of the PCP- n membranes suggests a promising future for their application.
研究领域:
材料科学
·
燃料电池技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）