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751.
In the present work, we report one-step preparation of phthalocyanine/acid-activated multiwalled carbon nanotube/polypyrrole modified pencil graphite electrodes (Pc/AA-MWCNT/PPy/PGE) for electrochemical supercapacitor applications. Conducting polymer-based ternary electrode materials were prepared by in situ electropolymerization of pyrrole in the presence of AA-MWCNT and Pc. The structures of prepared electrodes were characterized by different techniques such as Fourier transform infrared, scanning electron microscopy, energy-dispersive spectrometer, atomic force microscope, Brunauer-Emmett-Teller, cyclic voltammetry, and electrochemical impedance spectroscopy to examine their structural and electrochemical properties. This study examines for the first time supercapacitive properties of ZnPc/AA-MWCNT/PPy/PGE and CuPc/AA-MWCNT/PPy/PGE. The specific capacitances of electrodes have been found as 304 F/g for CuPc/AA-MWCNT/PPy/PGE and 117 F/g ZnPc/AA-MWCNT/PPy/PGE with 10 A/g charge-discharge current densities. When compared to all preparation electrode materials in the literature, CuPc/AA-MWCNT/PPy/PGE exhibited superior supercapacitive behavior. The synergistic effect of PPy, AA-MWCNT, and Pc with excellent physical interface presents better charge storage capacity and less charge transfer resistance. We observed that the Pc/AA-MWCNT/PPy/PGE electrodes can synergistically improve the charge storage property in comparison to its individual constituents. 相似文献
752.
Stefanie Grtner Angelina Graf Carla Triunfo Davide Laurenzi Stefan M. Schupp Gabriele Maoloni Giuseppe Falini Helmut Clfen 《International journal of molecular sciences》2022,23(13)
Biomaterials such as seashells are intriguing due to their remarkable properties, including their hierarchical structure from the nanometer to the micro- or even macroscopic scale. Transferring this nanostructure to generate nanostructured polymers can improve their electrical conductivity. Here, we present the synthesis of polypyrrole using waste seashell powder as a template to prepare a polypyrrole/CaCO3 composite material. Various synthesis parameters were optimized to produce a composite material with an electrical conductivity of 2.1 × 10−4 ± 3.2 × 10−5 S/cm. This work presents the transformation of waste seashells into sustainable, electronically conductive materials and their application as an antistatic agent in polymers. The requirements of an antistatic material were met for a safety shoe sole. 相似文献
753.
Jiankun Huang Jingbin Zeng Xue Zhang Gengchen Guo Rui Liu Zifeng Yan Yadong Yin 《Small (Weinheim an der Bergstrasse, Germany)》2022,18(1):2104706
Achieving high sensitivity over a broad pressure range remains a great challenge in designing piezoresistive pressure sensors due to the irreconcilable requirements in structural deformability against extremely high pressures and piezoresistive sensitivity to very low pressures. This work proposes a hybrid aerogel/hydrogel sensor by integrating a nanotube structured polypyrrole aerogel with a polyacrylamide (PAAm) hydrogel. The aerogel is composed of durable twined polypyrrole nanotubes fabricated through a sacrificial templating approach. Its electromechanical performance can be regulated by controlling the thickness of the tube shell. A thicker shell enhances the charge mobility between tube walls and thus expedites current responses, making it highly sensitive in detecting low pressure. Moreover, a nucleotide-doped PAAm hydrogel with a reversible noncovalent interaction network is harnessed as the flexible substrate to assemble the aerogel/hydrogel hybrid sensor and overcome sensing saturation under extreme pressures. This highly stretchable and self-healable hybrid polymer sensor exhibits linear response with high sensitivity (Smin > 1.1 kPa?1), ultrabroad sensing range (0.12–≈400 kPa), and stable sensing performance over 10 000 cycles at the pressure of 150 kPa, making it an ideal sensing device to monitor pressures from human physiological signals to significant stress exerted by vehicles. 相似文献
754.
Kang Zhang Naiwen Kang Bo Zhang Ruijie Xie Jingyu Zhu Binghua Zou Yihan Liu Yuanyuan Chen Wei Shi Weina Zhang Wei Huang Jiansheng Wu Fengwei Huo 《Advanced Electronic Materials》2020,6(8)
The commonly used electrocardiogram monitoring electrodes (hydrogel electrodes, fabric electrodes, etc.) suffer from fast degradation of signal quality due to water loss. Therefore, such electrodes are not suitable for long‐term monitoring. Herein, the conductive polymer polypyrrole (PPy) is polymerized in situ on goat leather, and the obtained conductive leather is used as a wearable dry electrode to contact human skin and collect electrophysiological signals for daily health monitoring. Because of its own surface structure, the wearable dry leather electrode obtained by a simple method can form a conformal contact with the skin to reduce noise during electrical signal acquisition. In addition, PPy‐leather electrodes have good antibacterial properties and are more breathable and comfortable than the commercial Ag/AgCl gel electrode. Such an electrode is more suitable for long‐term health monitoring. 相似文献
755.
Xingxing Li Yanan Ma Peizhi Shen Chuankun Zhang Minglei Cao Shaojun Xiao Jinfeng Yan Shijun Luo Yihua Gao 《Advanced Materials Technologies》2020,5(8)
Ti3C2Tx MXene, as a new 2D material, with unique physical and chemical properties, is ideal for building high performance miniaturized electrochemical energy storage devices. However, the operating voltage window of Ti3C2Tx based microsupercapacitor (MSC) in symmetric structure is very narrow (≤0.6 V), which affects its practical application. Herein, a flexible asymmetric microsupercapacitor (AMSC) based on Ti3C2Tx//polypyrrole (PPy)/MnO2 is reported, where Ti3C2Tx is deposited on graphite paper (GP) by electrophoresis method as negative electrodes, MnO2 and PPy are electrochemically deposited on GP successively as positive electrodes, and polyvinyl alcohol/sulfuric acid (PVA/H2SO4) as the quasi‐solid electrolyte. This AMSC based on Ti3C2Tx//PPy/MnO2 operates at 1.2 V voltage window, which is two times wider than symmetric Ti3C2Tx based MSC. And its maximum areal capacitance and areal energy density can reach up to 61.5 mF cm−2 and 6.73 µWh cm−2 respectively. Moreover, three above AMSCs in series connection can turn on three lights after being charged. And the AMSC also shows high flexibility under mechanical bending level (bending angle with 0°–180°). The flexible AMSC based on Ti3C2Tx//PPy/MnO2 with ultrahigh energy density is a promising candidate for exploiting and fabricating next‐generation miniature integrated energy storage devices. 相似文献
756.
《Advanced Materials Interfaces》2018,5(8)
Many electrochemical biosensors are developed and widely used for the detection of biological responses. However, there is a limitation like increasing the surface area of the working electrode for the improvement of sensitivity. Nanoimprint lithography (NIL) is a simple method that uses stamp and UV or thermally curable resins for fabricating nanopatterns and nanostructures at low cost and with high throughput and high resolution. Therefore, the fabrication of a nanostructure on the working electrode using nanoimprint lithography can improve not only the sensitivity of a biosensor to biological responses by increasing the surface area of the working electrode but also the mass production of nanopatterned electrodes. Here, a conducting polymer‐based UV‐curable resin is aimed to develop and to use it to fabricate a uniform nanostructure on the working electrode. The 150 nm pillar patterns on a Pt electrode are created using polydimethylsiloxane stamps and KIMM ANT‐6HO UV‐NIL system and measured electrochemical signals using cyclic voltammetry. Furthermore, glucose oxidase is immobilized on the conducting polymer‐imprinted electrode. The developed electrochemical biosensor successfully measures glucose levels across a dynamic range of 0.1 µg mL−1 to 200 mg mL−1 under optimized conditions. 相似文献
757.
Zuan‐Tao Lin Yaxi Li Jianhua Gu Huie Wang Zhuan Zhu Xia Hong Zijing Zhang Qinqin Lu Jingyi Qiu Xifan Wang Jiming Bao Tianfu Wu 《Advanced functional materials》2018,28(31)
Detection of extracutaneous melanoma is still challenging and is of importance in improving survival rate. In this report, an ultrasensitive biosensor is constructed where a C‐reactive protein (CRP) aptamers based molecular recognition core and a conductive polypyrrole (PPy) nanowire mesh based signal amplifier are developed. The conductive PPy nanowire (less than 10 nm in diameter) mesh architecture is uniformly dispersed within polymeric matrix via template‐free in situ synthesis. Serum CRP levels are quantitatively analyzed through monitoring the conductance change caused by polymeric network shrinkage upon the aptamer‐CRP binding. The limit of detection (LOD) of the polymeric sensor for human CRP sample can reach 7.85 × 10?19m . This CRP‐specific biosensor and a commercial CRP enzyme‐linked immunosorbent assay (ELISA) kit are used to perform side‐by‐side measurement of serum CRP in melanoma patients. The results indicate that this conductive polymeric senor is highly sensitive and selective in accurately discriminating melanoma patients from healthy controls using serum CRP as a biomarker, which is further validated by a commercial human CRP ELISA kit. Collectively, this novel ultrasensitive nanowire‐based polymeric biosensor may hold promise in biomarker detection and diagnosis of cancer. 相似文献
758.
本征型导电高分子电磁干扰屏蔽材料研究进展 总被引：9，自引：1，他引：9
综述了本征型导电高分子材料及其与常规高分子、金属复合材料在电磁干扰屏蔽领域的研究进展。相比于金属系电磁干扰屏蔽材料,本征型导电高分子材料不仅具有质轻、易合成、电导率可调、环境稳定性好等优点,而且它们的主要屏蔽特征为吸收损耗,不同于金属材料的反射损耗特征。单纯采用本征型导电高分子材料很难获得优异的电磁干扰屏蔽效能,通过将本征型导电高分子与金属材料的复合可极大提高它们的电磁干扰屏蔽效能,同时可以控制屏蔽材料的吸收/反射损耗比。 相似文献
759.
采用电化学方法制备了对甲基苯磺酸钠掺杂的聚吡咯(TsONa/PPy)锂离子电池正极材料和二氧化钛纳米管阵列(TiO_2NT)负极材料。利用扫描电子显微镜和X射线能量色散光谱仪研究了样品的微观结构及形貌,并进一步组装成全电池,利用恒流充–放电和循环伏安(CV)技术测试了其电化学性能。结果表明:对甲基苯磺酸钠掺杂的聚吡咯正极材料是由直径为3μm左右的微球组成,二氧化钛负极材料则呈现三维有序纳米管阵列形貌,两种电极材料的表面皆凸凹不平;由二者组成的全电池首次放电比容量约为105 mA·h/g,经过50次循环后,可逆放电比容量仍保持在65 mA·h/g,表现了良好的循环稳定性,此外还表现了良好的倍率性能。 相似文献
760.
《国际聚合物材料杂志》2012,61(2):107-114
Composite films of polypyrrole-poly(vinyl sulphonic acid) (Ppy-PVS), polypyrrole-p-toluene sulphonic acid (Ppy-pTS) and polypyrrole-dodecylbenzene sulphonic acid (Ppy-DBS) were synthesized on ITO coated glass, using electrochemical polymerization. The synthesized films were characterized using electrochemical technique, electrical conductivity, UV-Vis spectroscopy, FTIR spectra, and scanning electron microscopy (SEM). This study reveals that Ppy-PVS composite films provide a polymer matrix with very good mechanical and environmental stability, uniform surface morphology, and higher conductivity, which are suitable for the immobilization of biocomponent. 相似文献