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Overoxidized poly(3,4-ethylenedioxythiophene)-overoxidized polypyrrole composite films with enhanced

《化学科学与工程前沿(英文)》 2023年 第17卷 第6期   页码 735-748 doi: 10.1007/s11705-022-2262-z

摘要: In this study, a simple and effective method was proposed to improve the electrocatalytic ability of overoxidized poly(3,4-ethylenedioxythiophene)-overoxidized polypyrrole composite films modified on glassy carbon electrode for rutin and luteolin determination. The composite electrode was prepared by cyclic voltammetry copolymerization with LiClO4-water as the supporting electrolyte. The peak current of rutin and luteolin on the composite electrode gradually decreased or even disappeared with the increase in the positive potential limit. After incubation in NaOH–ethanol solution with a volume ratio of 1:1, the composite electrodes prepared at positive potential limit greater than 1.5 V exhibited enhanced differential pulse voltammetry peak currents, reduced charge transfer resistance, larger effective specific surface area and higher electron transfer rate constant. The composite electrode prepared in the potential range of 0–1.7 V showed optimal electrocatalytic performance. The X-ray photoelectron spectroscopy results indicated that the content of –SO2/–SO and –C=N– groups in the composite film increased significantly after incubation. Further, the Raman spectra and Fourier transform infrared spectra revealed that the thiophene ring structure changed from benzene-type to quinone-type, and the quinone-type pyrrole ring was formed. The electrocatalytic mechanism of the composite film was proposed based on the experimental results and further verified by Density Functional Theory calculation.

关键词: overoxidized poly(3     4-ethylenedioxythiophene)-overoxidized polypyrrole     rutin     luteolin     incubation     electrocatalytic mechanism    

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) electrodes with enhanced

《化学科学与工程前沿(英文)》 2023年 第17卷 第2期   页码 206-216 doi: 10.1007/s11705-022-2203-x

摘要: Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is an important organic electrode for solution-processed low-cost electronic devices. However, it requires doping and post-solvent treatment to improve its conductivity, and the chemicals used for such treatments may affect the device fabrication process. In this study, we developed a novel route for exploiting ultrafast lasers (femtosecond and picosecond laser) to simultaneously enhance the conductivity and transparency of PEDOT:PSS films and fabricate patterned solution-processed electrodes for electronic devices. The conductivity of the PEDOT:PSS film was improved by three orders of magnitude (from 3.1 to 1024 S·cm–1), and high transparency of up to 88.5% (average visible transmittance, AVT) was achieved. Raman and depth-profiling X-ray photoelectron spectroscopy revealed that the oxidation level of PEDOT was enhanced, thereby increasing the carrier concentration. The surface PSS content also decreased, which is beneficial to the carrier mobility, resulting in significantly enhanced electrical conductivity. Further, we fabricated semitransparent perovskite solar cells using the as-made PEDOT:PSS as the transparent top electrodes, and a power conversion efficiency of 7.39% was achieved with 22.63% AVT. Thus, the proposed route for synthesizing conductive and transparent electrodes is promising for vacuum and doping-free electronics.

关键词: PEDOT:PSS     ultrafast laser     transparent electrode     ST-PSCs     patterning    

Fabrication of N-doped carbon nanobelts from a polypyrrole tube by confined pyrolysis for supercapacitors

Wei Wang, Haijun Lv, Juan Du, Aibing Chen

《化学科学与工程前沿(英文)》 2021年 第15卷 第5期   页码 1312-1321 doi: 10.1007/s11705-020-2033-7

摘要: In this present work, N-doped carbon nanobelts (N-CNBs) were prepared by a confined-pyrolysis approach and the N-CNBs were derived from a polypyrrole (Ppy) tube coated with a compact silica layer. The silica layer provided a confined space for the Ppy pyrolysis, thereby hindering the rapid overflow of pyrolysis gas, which is the activator for the formation of carbonaceous materials. At the same time, the confined environment can activate the carbon shell to create a thin wall and strip the carbon tube into belt morphology. This process of confined pyrolysis realizes self-activation during the pyrolysis of Ppy to obtain the carbon nanobelts without adding any additional activator, which reduces pollution and preparation cost. In addition, this approach is simple to operate and avoids the disadvantages of other methods that consume time and materials. The as-prepared N-CNB shows cross-linked nanobelt morphology and a rich porous structure with a large specific surface area. As supercapacitor electrode materials, the N-CNB can present abundant active sites, and exhibits a specific capacitance of 246 F·g , and excellent ability with 95.44% retention after 10000 cycles. This indicates that the N-CNB is an ideal candidate as a supercapacitor electrode material.

关键词: carbon nanobelts     polypyrrole     N-doped     confined pyrolysis     supercapacitor    

Hierarchically porous cellulose nanofibril aerogel decorated with polypyrrole and nickel-cobalt layered

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1593-1607 doi: 10.1007/s11705-023-2348-2

摘要: With increasing emphasis on green chemistry, biomass-based materials have attracted increased attention regarding the development of highly efficient functional materials. Herein, a new pore-rich cellulose nanofibril aerogel is utilized as a substrate to integrate highly conductive polypyrrole and active nanoflower-like nickel-cobalt layered double hydroxide through in situ chemical polymerization and electrodeposition. This ternary composite can act as an effective self-supported electrode for the electrocatalytic oxidation of glucose. With the synergistic effect of three heterogeneous components, the electrode achieves outstanding glucose sensing performance, including a high sensitivity (851.4 µA·mmol−1·L·cm−2), a short response time (2.2 s), a wide linear range (two stages: 0.001−8.145 and 8.145−35.500 mmol·L−1), strong immunity to interference, outstanding intraelectrode and interelectrode reproducibility, a favorable toxicity resistance (Cl), and a good long-term stability (maintaining 86.0% of the original value after 30 d). These data are superior to those of some traditional glucose sensors using nonbiomass substrates. When determining the blood glucose level of a human serum, this electrode realizes a high recovery rate of 97.07%–98.89%, validating the potential for high-performance blood glucose sensing.

关键词: cellulose nanofibril     aerogel     nickel-cobalt layered double hydroxide     polypyrrole     nonenzymatic glucose sensor    

Molecular tailoring to improve polypyrrole hydrogels’ stiffness and electrochemical energy storage capacity

Evelyn Chalmers, Yi Li, Xuqing Liu

《化学科学与工程前沿(英文)》 2019年 第13卷 第4期   页码 684-694 doi: 10.1007/s11705-019-1817-0

摘要: This research looks at ways of tailoring and improving the stiffness of polypyrrole hydrogels for use as flexible supercapacitor electrodes. Molecules providing additional cross-linking between polypyrrole chains are added post-polymerisation but before gelation, and are found to increase gel stiffness by up to 600%, with the degree of change dependent on reactant type and proportion. It was also found that addition of phytic acid led to an increase in pseudocapacitive behaviour of the hydrogel, and thus a maximum specific capacitance of 217.07 F·g could be achieved. This is an increase of 140% compared to pristine polypyrrole hydrogels produced by this method.

关键词: supercapacitor     polypyrrole     hydrogel     strengthening     electrochemical    

Polyaniline‒polypyrrole nanocomposites using a green and porous wood as support for supercapacitors

Jian LI, Yue JIAO

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 137-143 doi: 10.15302/J-FASE-2019257

摘要:

Wood is an ideal type of support material whose porous structure and surface functional groups are beneficial for deposition of various guest substances for different applications. In this paper, wood is employed as a porous support, combined with two kinds of conductive polymers (i.e., polyaniline (PANI) and polypyrrole (PPy)) using an easy and fast liquid polymerization method. Scanning electron microscope observations indicate that the PANI‒PPy complex consists of nanoparticles with a size of ~20 nm. The interactions between oxygen-containing groups in the wood and the nitrogen composition of PANI‒PPy were verified by Fourier transform infrared spectroscopy. The self-supported PANI‒PPy/wood composite is capable of acting as a free-standing supercapacitor electrode, which delivers a high gravimetric specific capacitance of 360 F·g at 0.2 A·g .

关键词: wood     polypyrrole     polyaniline     supercapacitors     nanocomposites    

Erratum to: Polypyrrole@NiCo hybrid nanotube arrays as high performance electrocatalyst for hydrogen

Shenghua Ye, Gaoren Li

《化学科学与工程前沿(英文)》 2019年 第13卷 第4期   页码 845-845 doi: 10.1007/s11705-019-1879-z

Flexible, ultrathin, and multifunctional polypyrrole/cellulose nanofiber composite films with outstanding

《化学科学与工程前沿(英文)》 2023年 第17卷 第8期   页码 1028-1037 doi: 10.1007/s11705-022-2251-2

摘要: Electrodes that combine energy storage with mechanical and photothermal performance are necessary for efficient development and use of flexible energy storage and conversion devices. In this study, the flexible, ultrathin, and multifunctional polypyrrole/cellulose nanofiber composite films were fabricated via a one-step “soak and polymerization” method. The dense sandwich structure and strong interfacial interaction endowed polypyrrole/cellulose nanofiber composite films with excellent flexibility, outstanding mechanical strength, and desired toughness. Interestingly, the polypyrrole/cellulose nanofiber composite film electrodes with quaternary amine functionalized cellulose nanofiber had the highest specific mass capacitance (392.90 F∙g–1) and specific areal capacitance (3.32 F∙cm–2) than the electrodes with unmodified and carboxyl functionalized cellulose nanofibers. Further, the polypyrrole/cellulose nanofiber composite films with sandwich structure had excellent photothermal conversion properties. This study demonstrated a feasible and versatile method for preparing of multifunctional composite films, having promising applications in various energy storage fields.

关键词: cellulose nanofiber     electrochemical     photothermal conversion     polypyrrole    

Polypyrrole@NiCo hybrid nanotube arrays as high performance electrocatalyst for hydrogen evolution reaction

Shenghua Ye, Gaoren Li

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 473-480 doi: 10.1007/s11705-018-1724-9

摘要:

The polypyrrole(PPy)@NiCo hybrid nanotube arrays have been successfully fabricated as a high performance electrocatalyst for hydrogen evolution reaction (HER) in alkaline solution. The strong electronic interactions between PPy and NiCo alloy are confirmed by X-ray photoelectron spectroscopy and Raman spectra. Because these interations can remarkably reduce the apparent activation energy (Ea) for HER and enhance the turnover frequency of catalysts, the electrocatalytic performance of PPy@NiCo hybrid nanotube arrays are significantly improved. The electrochemical tests show that the PPy@NiCo hybrid catalysts exhibit a low overpotential of ~186 mV at 10.0 mA·cm2 and a small tafel slope of 88.6 mV·deg1 for HER in the alkaline solution. The PPy@NiCo hybrid nanotubes also exhibit high catalytic activity and high stability for HER.

关键词: NiCo alloy     polypyrrole     hybrid nanotube     electrocatalyst     hydrogen evolution reaction    

ZnFe2O4/BiVO4 Z-scheme heterojunction for efficient visible-light photocatalytic

《化学科学与工程前沿(英文)》 2023年 第17卷 第11期   页码 1728-1740 doi: 10.1007/s11705-023-2322-z

摘要: A novel Z-scheme ZnFe2O4/BiVO4 heterojunction photocatalyst was successfully synthesized using a convenient solvothermal method and applied in the visible light photocatalytic degradation of ciprofloxacin, which is a typical antibiotic contaminant in wastewater. The heterostructure of as-synthesized catalysts was confirmed using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy characterizations. Compared with the single-phase counterparts, ZnFe2O4/BiVO4 demonstrated considerably enhanced photogenerated charge separation efficiencies because of the Z-scheme transfer mechanism of electrons between the composite photocatalysts. Consequently, the 30% ZnFe2O4/BiVO4 catalyst afforded a degradation rate of up to 97% of 20 mg/L ciprofloxacin under 30 min of visible light irradiation with a total organic carbon removal rate of 50%, which is an excellent activity compared with ever reported BiVO4-based catalysts. In addition, the liquid chromatography-mass spectrometry and quantitative structure-activity relationships model analyses demonstrated that the toxicity of the intermediates was lower than that of the parent ciprofloxacin. Moreover, the as-synthesized ZnFe2O4/BiVO4 heterojunctions were quite stable and could be reused at least four times. This study thus provides a promising Z-scheme heterojunction photocatalyst for the efficient removal and detoxication of antibiotic pollutants from wastewater.

关键词: ZnFe2O4/BiVO4     Z-scheme heterojunction     photocatalytic degradation     ciprofloxacin    

Li4SiO4-coated LiNi0.5Mn1.5O4 as the high performance

Shifeng YANG, Wenfeng REN, Jian CHEN

《能源前沿(英文)》 2017年 第11卷 第3期   页码 374-382 doi: 10.1007/s11708-017-0494-2

摘要: The preparation of Li SiO -coated LiNi Mn O materials by sintering the SiO -coated nickel-manganese oxides with lithium salts using abundant and low-cost sodium silicate as the silicon source was reported. The samples were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. It was found that a uniform and complete SiO coating layer could be obtained at a suitable pH value of 10, which transformed to a good Li SiO coating layer afterwards. When used as the cathode materials for lithium-ion batteries, the Li SiO -coated LiNi Mn O samples deliver a better electrochemical performance in terms of the discharge capacity, rate capability, and cycling stability than that of the pristine material. It can still deliver 111.1 mAh/g at 20 C after 300 cycles, with a retention ratio of 93.1% of the stable capacity, which is far beyond that of the pristine material (101.3 mAh/g, 85.6%).

关键词: lithium-ion batteries     cathode material     LiNi0.5Mn1.5O4     lithium-ion conductor     coating    

Enhanced debromination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) by zero-valent zinc with ascorbic

Chaojin Jiang, Xiaoqian Jiang, Lixun Zhang, Yuntao Guan

《环境科学与工程前沿(英文)》 2020年 第14卷 第3期 doi: 10.1007/s11783-020-1224-2

摘要: Highly efficient debromination of BDE-47 was achieved in the ZVZ/AA system. BDE-47 debromination by the ZVZ/AA can be applied to a wide range of pH. AA inhibits the formation of (hydr)oxide and accelerates the corrosion of ZVZ. Reduction mechanism of BDE-47 debromination by the ZVZ/AA system was proposed. A new technique of zero-valent zinc coupled with ascorbic acid (ZVZ/AA) was developed and applied to debrominate the 2,2′,4,4′-Tetrabromodiphenyl ether (BDE-47), which achieved high conversion and rapid debromination of BDE-47 to less- or non-toxic forms. The reaction conditions were optimized by the addition of 100 mg/L ZVZ particles and 3 mmol/L AA at original solution pH= 4.00 using the solvent of methanol/H2O (v:v= 4:6), which could convert approximately 94% of 5 mg/L BDE-47 into lower-brominated diphenyl ethers within a 90 min at the ZVZ/AA system. The high debromination of BDE-47 was mainly attributed to the effect of AA that inhibits the formation of Zn(II)(hydr)oxide passivation layers and promotes the corrosion of ZVZ, which leads to increase the reactivity of ZVZ. Additionally, ion chromatography and gas chromatography mass spectrometry analyses revealed that bromine ion and lower-debromination diphenyl ethers formed during the reduction of BDE-47. Furthermore, based on the generation of the intermediates products, and its concentration changes over time, it was proposed that the dominant pathway for conversion of BDE-47 was sequential debromination and the final products were diphenyl ethers. These results suggested that the ZVZ/AA system has the potential for highly efficient debromination of BDE-47 from wastewater.

关键词: 2     2′     4     4′-tetrabromodiphenyl ether (BDE-47)     Ascorbic acid     Reductive debromination     Zero-valent zinc    

Knockdown of RFC4 inhibits the cell proliferation of nasopharyngeal carcinoma and

《医学前沿(英文)》 2023年 第17卷 第1期   页码 132-142 doi: 10.1007/s11684-022-0938-x

摘要: Nasopharyngeal carcinoma (NPC) is a malignant tumor that mainly occurs in East and Southeast Asia. Although patients benefit from the main NPC treatments (e.g., radiotherapy and concurrent chemotherapy), persistent and recurrent diseases still occur in some NPC patients. Therefore, investigating the pathogenesis of NPC is of great clinical significance. In the present study, replication factor c subunit 4 (RFC4) is a key potential target involved in NPC progression via bioinformatics analysis. Furthermore, the expression and mechanism of RFC4 in NPC were investigated in vitro and in vivo. Our results revealed that RFC4 was more elevated in NPC tumor tissues than in normal tissues. RFC4 knockdown induced G2/M cell cycle arrest and inhibited NPC cell proliferation in vitro and in vivo. Interestingly, HOXA10 was confirmed as a downstream target of RFC4, and the overexpression of HOXA10 attenuated the silencing of RFC4-induced cell proliferation, colony formation inhibition, and cell cycle arrest. For the first time, this study reveals that RFC4 is required for NPC cell proliferation and may play a pivotal role in NPC tumorigenesis.

关键词: nasopharyngeal carcinoma     WGCNA     RFC4     proliferation    

4D打印定律 Article

Farhang Momeni, Jun Ni

《工程(英文)》 2020年 第6卷 第9期   页码 1035-1055 doi: 10.1016/j.eng.2020.01.015

摘要: 相应地,四维(4D)打印是一个涉及多个研究领域的制造工艺。4D打印保留了3D打印的一般属性(如减少材料浪费、消除注射模具、冲压模具和机械加工过程),并且随着时间的推移能实现产品第四维度的智能行为。3D和4D打印结构的主要区别是4D打印存在一个附加的维度,这个维度可以随着时间的推移进行智能进化。然而,目前还没有用于建模和预测这个附加维度的一般公式。本文从基本原理开始,导出并验证了一个具有特定格式的一般双指数公式,该公式可以模拟几乎所有4D结构的时间相关性行为(如水、光化学、光热、溶剂、pH、湿度、电化学、电热、超声波等响应)。研究表明,需要利用两种类型的时间常数来捕捉4D多材料的正确的时间相关性行为。本文引入了4D多材料结构中主动材料和被动材料的界面错配压力的概念,从而得到了两个时间常数之一。本文的结果从最基本的概念开始,并以控制方程结束,可以作为未来4D打印领域研究的一般设计原则,其中时间相关性行为应该被正确地理解、建模和预测。

关键词: 制造业     刺激响应材料     材料力学     时间常数     4D打印    

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要: Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词: synthesis     pyrimidin-4-amine derivatives     1     2     4-oxadiazole     insecticidal activity     structure-activity relationship    

标题 作者 时间 类型 操作

Overoxidized poly(3,4-ethylenedioxythiophene)-overoxidized polypyrrole composite films with enhanced

期刊论文

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) electrodes with enhanced

期刊论文

Fabrication of N-doped carbon nanobelts from a polypyrrole tube by confined pyrolysis for supercapacitors

Wei Wang, Haijun Lv, Juan Du, Aibing Chen

期刊论文

Hierarchically porous cellulose nanofibril aerogel decorated with polypyrrole and nickel-cobalt layered

期刊论文

Molecular tailoring to improve polypyrrole hydrogels’ stiffness and electrochemical energy storage capacity

Evelyn Chalmers, Yi Li, Xuqing Liu

期刊论文

Polyaniline‒polypyrrole nanocomposites using a green and porous wood as support for supercapacitors

Jian LI, Yue JIAO

期刊论文

Erratum to: Polypyrrole@NiCo hybrid nanotube arrays as high performance electrocatalyst for hydrogen

Shenghua Ye, Gaoren Li

期刊论文

Flexible, ultrathin, and multifunctional polypyrrole/cellulose nanofiber composite films with outstanding

期刊论文

Polypyrrole@NiCo hybrid nanotube arrays as high performance electrocatalyst for hydrogen evolution reaction

Shenghua Ye, Gaoren Li

期刊论文

ZnFe2O4/BiVO4 Z-scheme heterojunction for efficient visible-light photocatalytic

期刊论文

Li4SiO4-coated LiNi0.5Mn1.5O4 as the high performance

Shifeng YANG, Wenfeng REN, Jian CHEN

期刊论文

Enhanced debromination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) by zero-valent zinc with ascorbic

Chaojin Jiang, Xiaoqian Jiang, Lixun Zhang, Yuntao Guan

期刊论文

Knockdown of RFC4 inhibits the cell proliferation of nasopharyngeal carcinoma and

期刊论文

4D打印定律

Farhang Momeni, Jun Ni

期刊论文

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

期刊论文