BC/CoNi2S4@PPy柔性复合电极材料的制备及电化学性能

本文采用溶剂热、原位聚合和真空抽滤相结合的方法制备了用于超级电容器的细菌纤维素/镍钴硫化物/聚吡咯(BC/CoNi2S4@PPy)柔性电极材料,通过X 射线衍射、场发射扫描电镜、红外光谱、氮气吸脱附、拉伸强度和接触角表征了材料的形貌结构、组成、机械性能和亲水性,并采用循环伏安法和恒电流充放电测试了复合材料的电化学性能....     

Lignin as a Partial Polyol Replacement in Polyurethane Flexible Foam

This study was focused on evaluating the suitability of a wide range of lignins, a natural polymer isolated from different plant sources and chemical extractions, in replacing 20 wt.% of petroleum-based polyol in the formulation of PU flexible foams. The main goal was to investigate the effect of unmodified lignin incorporation on the foam’s structural, mechanical, and thermal properties. The hydroxyl contents of the commercial lignins were measured using phosphorus nuclear magnetic resonance (³¹P NMR) spectroscopy, molar mass distributions with gel permeation chromatography (GPC), and thermal properties with differential scanning calorimetry (DSC) techniques. The results showed that incorporating 20 wt.% lignin increased tensile, compression, tear propagation strengths, thermal stability, and the support factor of the developed PU flexible foams. Additionally, statistical analysis of the results showed that foam properties such as density and compression force deflection were positively correlated with lignin’s total hydroxyl content. Studying correlations between lignin properties and the performance of the developed lignin-based PU foams showed that lignins with low hydroxyl content, high flexibility (low T_g), and high solubility in the co-polyol are better candidates for partially substituting petroleum-based polyols in the formulation of flexible PU foams intended for the automotive applications.     

印刷有机数字电路及应用

印刷有机电子技术是基于印刷原理的有机电子器件制造技术,是指将有机电子材料配制成功能性油墨,用印刷方式来制造电子器件与系统的方法,其发展涉及到材料化学、微电子学等多个学科方面的知识。其独特的制造方式和器件形态具有柔性、低成本、大面积制造等优势,并且与传统硅基电子器件在应用场合上形成了互补,在生物传感、电子皮肤、柔性显示等领域展示出优势。为了及时跟进这一快速发展的领域,对领域的发展有宏观的把握,本文从印刷技术和电路系统的角度进行了全面概述,介绍了喷墨打印、丝网印刷和转印印刷等印刷技术和基于印刷技术制备的有机数字电路(反相器、与非门、环形振荡器、D触发器),以及实现功能化的印刷电子应用(RFID、电子皮肤、OLED显示驱动背板等);最后,对本领域目前存在的问题和未来发展方向做了简要探讨。     

A low-temperature X-ray diffraction study of the Cu2ZnSnSe4 thin films

Low-temperature XRD measurements were performed to confirm the phase composition and structural parameters of the electrochemically deposited Cu₂ZnSnSe₄ thin films on flexible metal substrates.     

Flexible Polymer–Organic Solar Cells Based on P3HT:PCBM Bulk Heterojunction Active Layer Constructed under Environmental Conditions

In this study, some crucial parameters were determined of flexible polymer–organic solar cells prepared from an active layer blend of poly(3-hexylthiophene) (P3HT) and the fullerene derivative [6,6]-phenyl-C₆₁-butyric acid methyl ester (PCBM) mixed in 1:1 mass ratio and deposited from chlorobenzene solution by spin-coating on poly(ethylene terephthalate) (PET)/ITO substrates. Additionally, the positive effect of an electron transport layer (ETL) prepared from zinc oxide nanoparticles (ZnO np) on flexible photovoltaic elements’ performance and stability was investigated. Test devices with above normal architecture and silver back electrodes deposed by magnetron sputtering were constructed under environmental conditions. They were characterized by current-voltage (I–V) measurements, quantum efficiency, impedance spectroscopy, surface morphology, and time–degradation experiments. The control over morphology of active layer thin film was achieved by post-deposition thermal treatment at temperatures of 110–120 °C, which led to optimization of device morphology and electrical parameters. The impedance spectroscopy results of flexible photovoltaic elements were fitted using two R||CPE circuits in series. Polymer–organic solar cells prepared on plastic substrates showed comparable current–voltage characteristics and structural properties but need further device stability improvement according to traditionally constructed cells on glass substrates.     

Quadruply BN-Fused Tetrathia[8]circulenes with Flexible Frameworks: Synthesis,Structures and Properties

Quadruply BN-fused tetrathia[8]circulenes were synthesized through four-fold electrophilic borylation. The single-crystal X-ray diffraction analysis revealed that the BN-fused tetrathia[8]circulene with peripheral phenyl groups exhibits crystal polymorphism, in which the circulene core adopts both planar and saddle conformations in the solid state. The experimental and theoretical studies revealed that the weaker aromaticity of azaborine compared with benzene renders the flexibility of the BN-fused tetrathia[8]circulenes.     

Capacitive Properties of the Binder‐Free Electrode Prepared from Carbon Derived from Cotton and Reduced Graphene Oxide

The binder‐free composite films of reduced graphene oxide (rGO ) and activated carbon derived from cotton (aCFC ) have been fabricated and used as electrodes for electrochemical capacitors (ECs ) to avoid the decrease of capacitive performance in traditional process caused by the additional binder. The optimal aCFC is prepared at 850 °C when the mass ratio of carbon and potassium hydroxide is 1 to 4. The optimal composite film prepared from the mass ratio of aCFC /GO =2/1 exhibits porous structure, and has a specific surface area of 849.6 m²•g⁻¹ and a total pore volume of 0.61 mL •g⁻¹. Based on the two‐electrode system testing in 6.0 mol/L KOH electrolyte, the optimal composite has specific capacitance of about 202 F•g⁻¹, 374 mF •cm⁻² and 116 F•cm⁻³ in terms of mass, area and volume, and shows excellent rate capability and good cyclic stability (91.7% retention of the initial capacitance after 5000 cycles). Furthermore, the assembled solid‐state ECs by using KOH /polyvinyl alcohol as electrolyte show good mechanical stability and capacitive performances after repeated bending cycles. It is proved that this method is effective to fabricate binder‐free electrodes for ECs and will open up a novel route for the reuse of waste cotton.     

光子晶体结构色织物研究进展

针对结构色织物难以产业化的现状,从光学效应和能够产生结构色的周期性结构两个角度系统介绍了结构色织物生色机理。随后,按照结构色织物表面光子晶体结构特征、所用光子晶体基元种类及结构色制备方法,对结构色织物进行了系统分类归纳,并指出了各自的优缺点。此外,现有结构色织物研究均为基于已有纳米粒子尺寸来表征对应结构色颜色,缺乏根据实际颜色需求选取光子晶体尺寸的研究。我们根据现有文献报道的光子晶体基元尺寸与所得结构色织物颜色种类的对应关系,通过计算得到了根据所需织物颜色种类确定光子晶体基元尺寸的公式。最后总结了结构色织物制备存在的问题,并给出了合理建议。     

Citronellol-Based Long-Lasting Antibacterial Cotton Fabrics without Bacterial Resistance

Antibacterial cotton helps prevent the growth and spread of harmful microorganisms, reduces the risk of infection, and has a prolonged service life by reducing bacterial degradation. However, most antibacterial agents used are toxic to humans and the environment. Citronellol-poly(N,N-dimethyl ethyl methacrylate) (CD), a highly effective antibacterial polymer, is synthesized from natural herbal essential oils (EOs). CD exhibited efficient, rapid bactericidal activity against Gram-positive, Gram-negative, and drug-resistant bacteria. Citronellol's environmental benignity makes CDs less hemolytic. Notably, negligible drug resistance developed after 15 bacterial subcultures. The CD-treated cotton fabric displayed better antibacterial performance than AAA-grade antibacterial fabric, even after repeated washing. This study extends the practical application of EOs to antibacterial surfaces and fabrics, which is promising for use in personal care products and medical settings.     

Hydrogen peroxide bleaching of cotton in ultrasonic energy

It is well known that, conventional hydrogen peroxide bleaching process is an important and a specific step for wet processors; however it has some problems such as long time, high energy consumption. On the other hand, using ultrasonic energy in bleaching is an alternative method for the conventional processes.

In this work, 100% cotton materials of different forms such as raw fibre, ring-spun yarns and knitted fabrics produced from these cottons, were treated with hydrogen peroxide in two different concentrations (5 mL/L and 10 mL/L), at three different temperatures (20 °C, 30 °C, 40 °C) and times (20 min, 30 min, 60 min). Whiteness Index of the samples were then measured spectrophotometrically and the overall results were compared.