炭纸/石墨基体NiHCF膜的碱金属离子分离性能

采用毛细化学沉积法在炭纸/石墨颗粒复合导电基体的微孔通道内合成铁氰化镍(Nickel hexacyanoferrate,NiHCF)薄膜,并考察了膜电极在碱金属溶液中的电控离子交换性能.通过扫描电子显微镜、能量色散谱、X射线光电子能谱、红外分子吸收光谱等分析了复合薄膜电极的表面形貌及组成;利用离子色谱检测了再生液中碱金属离子浓度变化;应用循环伏安法在1 mol · L~(-1) KNO_3/C_sNO_3溶液中考察了膜电极的离子交换容量、循环寿命与再生能力.结果表明:炭纸/石墨复合基体具有三维多孔结构特征,复合基体NiHCF膜电极具有大的离子交换容量、低的扩散阻力、良好的循环稳定性与再生能力,可用于碱金属离子的选择性分离.     

聚吡咯／多壁碳纳米管的合成及电化学行为

在含有多壁碳纳米管(MWCNT)的十二烷基苯磺酸钠(SDBS)溶液中电化学氧化吡咯(Py)制得聚吡咯/多壁碳纳米管(PPy/MWCNT)导电复合膜。研究了聚合温度、电流密度、吡咯浓度对PPy/MWC-NT复合膜沉积量的影响,采用交流阻抗谱(EIS)法研究了该导电复合膜的电化学行为,并用扫描电子显微镜对其表面形貌进行了观察。实验结果表明,随着温度的降低、电流密度及吡咯浓度的增大,复合膜沉积量变大。与纯PPy膜相比,PPy/MWCNT复合膜有更好的电子传递行为,而复合膜表面更加粗糙、疏松。     

Electrochemical quartz crystal impedance study of redox hydrogel mediators for amperometric enzyme electrodes

Quartz crystal impedance around the resonant frequency at 10 MHz of a composite quartz crystal resonator has been studied simultaneously with cyclic voltammetry. A modified quartz crystal with a redox hydrogel (poly(allylamine)-ferrocene cross-linked with glucose oxidase) and immersed in liquid electrolyte was used. Impedance parameters (R(f) and X(L)((f))) of the surface redox gel film were obtained by fitting the resonator transfer function |V(o)/V(i)| vs ω to a BVD equivalent circuit and analyzed with the multiple nonpiezoelectric layer model of Martin. Two limiting hydrogel layers of the same composition were studied while oxidizing and reducing the ferrocene/ferricenium moieties attached to the swollen polymer backbone: thin and thick redox hydrogel films. For the thin films, the Sauerbrey approximation was valid. The mass/thickness and film viscosity changes that resulted from the anion and water exchange were evaluated while redox switching the polymer on the assumption of negligible storage modulus G' and a density of 1. For thick gel layers, on the other hand, the penetration depth of the acoustic wave was far less than the film thickness, and a liquid-like behavior was apparent. Film storage modulus and film loss modulus were simultaneously evaluated with the cyclic voltammetry.     

电致变色纳米氧化镍薄膜的溶胶-凝胶法制备与表征

以无水氯化镍、乙醇为前驱液,加入适量的丁醇和柠檬酸为稳定剂,通过回流、水解得到稳定的溶胶;采用浸渍-提拉的方法在ITO导电玻璃上形成均匀的膜层;分析了溶胶制备中加水量的影响;研究了热处理温度对制备膜层的结构、光透过率的影响;对经过不同处理的膜层进行X射线衍射、透射电子显微镜、扫描电子显微镜、热重分析等研究表明:在空气中加热到350℃、保温30min薄膜分解为稳定的具有立方结构的NiO纳米晶;以氢氧化钾水溶液为电解质的循环伏安、电致变色实验结果表明制备的纳米氧化镍薄膜具有良好的电致变色特性.     

纳米结构聚苯胺和聚吡咯电活性的对比研究

采用简单的电化学聚合方法在FTO导电玻璃表面制备了纳米结构的聚苯胺(PANI)和聚吡咯(PPy),用扫描电镜(SEM)图和电化学循环伏安法分析了两种聚合物薄膜的形貌和电催化活性,结果表明,两种聚合物纳米形貌的不同导致了其电活性的差异。PANI内部颗粒状紧密层和外部蓬松网状疏松层的结构显著增大了膜的比表面积,相比PPy具有更好的电催化活性和更高的电池效率。     

Preparation and tribological properties of novel carbon nanotube self-assembled composite films

Carbon nanotube (CNT) composite thin films were prepared on a single-crystal silicon substrate by a self-assembling process from a specially formulated solution. Rare earth solution (RES) surface modification and appropriate acid-treatment methods were used to functionalise carbon nanotubes (CNTs). Silane coupling regent (3-mercaptopropyl trimethoxysilane (MPTS)) was prepared first. The terminal thiol groups (–SH) in the film was oxidised to sulphonic acid groups (–SO₃H) in situ to enhance the film with good chemisorption ability. Treated Caron nanotubes were deposited on the oxidised MPTS–SAM by means of chemisorption with the SO₃H group. The surface energy, chemical composition, phase transformation and surface morphology of the films were analysed using contact angle measurements, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and atomic force microscopy. As a result, a conclusion could be made that some lanthanum elements react with –SO₃H groups on the surface of the substrate by a chemical bond, which will improve the bonding strength between the films and the CNTs. Since the CNT thin films were well adhered to the silicon substrate, it might find promising application in the surface-modification of single-crystal Si and SiC in microelectromechanical systems (MEMS).     

A facile synthesis of α-Ni(OH)2-CNT composite films for supercapacitor application

The α-Ni(OH)₂-CNT composite films have been successfully synthesized by a simple chemical method and their supercapacitive properties were investigated by variation of CNT. The structural, compositional, morphological, wettability and electrochemical properties of the composite films were studied by using various characterization techniques. X-ray diffraction analysis revealed that the synthesized composite films are polycrystalline in nature. FT-Raman spectroscopy result showed the characteristic Raman band of CNT and α-Ni(OH)₂ which confirmed the formation of α-Ni(OH)₂-CNT composite. SEM micrographs showed porous microstructure of the synthesized films and hydrophilic nature of the films was confirmed from wettability studies. Furthermore, the effect of the variation of CNT on the electrochemical properties of the synthesized composite films was discussed. The electrochemical performance of the composite films was studied by using cyclic voltammetry (CV) and Galvanostatic charge–discharge (GCD) techniques. The α-Ni(OH)₂-CNT composite showed highest specific capacitance of 544 F g^?1 with high retention capability of 85% after 1500th cycle and excellent cycling stability.     

聚吡咯/聚砜复合膜修饰电极的制备及其对对苯二酚的电化学催化性能

采用循环伏安法电化学聚合制备了聚吡咯(PPY)/聚砜(PSF)复合膜修饰电极.结果发现:复合膜的正面(与工作电极接触的一面)是黑色的;而反面(与溶液接触的一面)是白色的.复合膜的表面形态和化学组分分别用SEM和FTIR表征,用电化学循环伏安法对PPY/PSF复合膜修饰电极的电化学催化性能进行了研究.实验结果表明:所得复合膜修饰电极电化学可逆性好并且对对苯二酚有显著的催化效果,其氧化峰电流在5～30mM的范围内与对苯二酚的浓度呈线性关系,表明该复合膜修饰电极在对苯二酚H2Q的监测方面将有潜在的用途.     

The solution growth route and characterization of electrochromic tungsten oxide thin films

Electrochromic tungsten oxide thin films were prepared by using an aqueous solution of Na₂WO₄·2H₂O and dimethyl sulfate. Various techniques were used for the characterization of the films such as X-ray diffraction, cyclic voltammetry, SEM analysis and VIS-spectroscopy. The thin film durability was tested in an aqueous solution of LiClO₄ (0.1 mol/dm³) for about 7000 cycles followed by cyclic voltammetry. No significant changes in the cyclic voltammograms were found, thus proving the high durability of the films.The optical transmittance spectra of coloured and bleached states showed significant change in the transmittance, which makes these films favorable for electrochromic devices.     

Polypyrrole/multiwall carbon nanotube nanocomposites electropolymerized on copper substrate

Polypyrrole/multiwall carbon nanotube (PPy/MWCNT) nanocomposites were successfully synthesized by electropolymerization of MWCNT-dispersed pyrrole solution on the surface of copper electrodes. The obtained nanocomposites were characterized with scanning electron microscopy (SEM), linear sweep voltammetry (LSV) and thermal gravimetric analysis (TGA). Polypyrrole structures which embraced the MWCNTs led to the formation of nanocomposite striated parallel walls. MWCNTs acted as appropriate substrates for electrodeposition of polypyrrole particulate structures and high yield synthesis of PPy was observed on them. Smooth PPy/MWCNT nanocomposite films were obtained on Cu electrodes by decreasing the potential scan rate. Thermogravimetric analysis showed that MWCNTs increased the thermal stability of polypyrrole.     

电化学法聚吡咯/碳纳米管复合膜的制备与表征

以对甲苯磺酸(PTSA)为掺杂剂、碳纳米管(CNTs)为增强相通过电化学恒电位法在不锈钢电极表面合成聚吡咯/碳纳米管(PPy/CNTs)复合膜.采用扫描电镜(SEM)和四探针测试仪对PPy/CNTs膜的微现形貌和电导率进行表征.通过交流阻抗谱(EIS)、循环伏安法(CV)研究了PPy/CNTs膜的电化学行为.系统研究了...     

Nickel oxide/polypyrrole/silver nanocomposites with core/shell/shell structure: Synthesis,characterization and their electrochemical behaviour with antimicrobial activities

Magnetic and conducting Nickel oxide–polypyrrole (NiO/PPy) nanoparticles with core–shell structure were prepared in the presence of Nickel oxide (NiO) in aqueous solution containing sodium dodecyl benzenesulfonate (SDBS) as a surfactant as well as dopant. A stable dispersion of silver (Ag) nanoparticles was synthesized by chemical (citrate reduction) method. NiO/PPy nanocomposites were added to the Ag colloid under stirring. Ag nanoparticles could be electrostatically attracted on the surface of NiO/PPy nanocomposites, leading to formation of NiO/PPy/Ag nanocomposites with core/shell/shell structure. The morphology, structure, particle size and composition of the products were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, cyclic voltammetry (CV) and current–voltage (I–V) analysis. The resultant nanocomposites have the good conductivity and excellent electrochemical and catalytic properties of PPy and Ag nanoparticles. Furthermore, the nanocomposites showed excellent antibacterial behaviour due to the presence of Ag nanoparticles in the composite. The thermal stability of NiO–PPy as well as NiO/PPy/Ag nanocomposites was higher than that of pristine PPy. Studies of IR spectra suggest that the increased thermal stability may be due to interactions between NiO and Ag nanoparticles with the PPy backbone.     

Integration of a carbon nanotube based electrode in silicon microtechnology to fabricate electrochemical transducers

An original approach was developed and validated for the fabrication of a carbon nanotube (CNT) electrode synthesized directly onto a carbon buffer thin film deposited on a highly doped monocrystalline silicon surface. The buffer layer of amorphous carbon thin film was deposited by physical vapour deposition on the silicon substrate before CNT synthesis. For this purpose, nickel was deposited on the carbon buffer layer by an electrochemical procedure and used as a catalyst for the CNT growth. The CNT synthesis was achieved by plasma enhanced chemical vapour deposition (PECVD) in an electron cyclotron resonance (ECR) plasma chamber using a C(2)H(2)/NH(3) gas mixture. In order to evaluate the electrochemical behaviour of the CNT-based electrode, the carbon layer and the silicon/carbon interface were studied. The resulting buffer layer enhanced the electronic transport from the doped silicon to the CNTs. The electrode surface was studied by XPS and characterized by both SEM and TEM. The electrochemical response exhibited by the resulting electrodes modified with CNTs was also examined by cyclic voltammetry. The whole process was found to be compatible with silicon microtechnology and could be envisaged for the direct integration of microsensors on silicon chips.     

Electrochemical studies of nano-structured diamond thin-film electrodes grown by microwave plasma CVD

In this paper, we report the investigation of the electrochemical properties of nano-structured diamond thin-film electrodes on porous silicon (PSi) synthesized by microwave plasma chemical vapor deposition (MPCVD). For the application, boron-doped and undoped diamond thin film has been performed and fabricated into an electrode device, and its microstructure, electrical and chemical properties have been studied. In order to enlarge the surface area of diamond electrodes, a negative bias was applied to the MPCVD process to deposit diamond thin film in a nano-structured form, so that its surface remained rough and nano-fine structured. Diamond thin films were analyzed by Raman spectroscopy and SEM. The morphology of boron-doped diamond thin films on PSi reveals nano-rods in the shape of diamond crystallites. Their electrochemical properties were evaluated by performing cyclic voltammetry (CV) measurement in inorganic K₄[Fe(CN)₆] in a K₂HPO₄ buffer solution. Boron-doped diamond thin film on PSi has demonstrated good electrochemical properties, with a larger redoxidation current of CV, due to its rough surface, which provides a more active electrochemical interface.     

聚吡咯复合膜材料制备、表征及阳离子交换性能研究

以活性炭纤维(ACF)为基底电极,采用电化学恒电位聚合法制备了掺杂十二烷基苯磺酸阴离子(DBS-)的聚吡咯(PPy)复合膜(ACF/PPy/DBS),分别考察了聚合时间为0.5h和1h的两种复合膜(APD0.5和APD1)对Ca2 的离子交换性能和电流效率,并使用扫描电镜表征和分析了复合膜的形貌。结果表明,复合膜的膜厚随聚合时间的延长而增加,膜厚与Ca2 的交换量成正比,但对离子交换的电流效率没有明显影响。在Ca2 的掺杂过程中,复合膜内Ca2 离子的掺杂量和电流效率随阴极极化电位的负移而增大;在Ca2 的解析过程中,复合膜内Ca2 离子解析的电流效率随阳极极化电位的正移而降低,但解析量的变化不大。     

Conducting‐Polymer Nanotubes Improve Electrical Properties,Mechanical Adhesion,Neural Attachment,and Neurite Outgrowth of Neural Electrodes

An in vitro comparison of conducting‐polymer nanotubes of poly(3,4‐ethylenedioxythiophene) (PEDOT) and poly(pyrrole) (PPy) and to their film counterparts is reported. Impedance, charge‐capacity density (CCD), tendency towards delamination, and neurite outgrowth are compared. For the same deposition charge density, PPy films and nanotubes grow relatively faster vertically, while PEDOT films and nanotubes grow more laterally. For the same deposition charge density (1.44 C cm^?2), PPy nanotubes and PEDOT nanotubes have lower impedance (19.5 ± 2.1 kΩ for PPy nanotubes and 2.5 ± 1.4 kΩ for PEDOT nanotubes at 1 kHz) and higher CCD (184 ± 5.3 mC cm^?2 for PPy nanotubes and 392 ± 6.2 mC cm^?2 for PEDOT nanotubes) compared to their film counterparts. However, PEDOT nanotubes decrease the impedance of neural‐electrode sites by about two orders of magnitude (bare iridium 468.8 ± 13.3 kΩ at 1 kHz) and increase capacity of charge density by about three orders of magnitude (bare iridium 0.1 ± 0.5 mC cm^?2). During cyclic voltammetry measurements, both PPy and PEDOT nanotubes remain adherent on the surface of the silicon dioxide while PPy and PEDOT films delaminate. In experiments of primary neurons with conducting‐polymer nanotubes, cultured dorsal root ganglion explants remain more intact and exhibit longer neurites (1400 ± 95 µm for PPy nanotubes and 2100 ± 150 µm for PEDOT nanotubes) than their film counterparts. These findings suggest that conducting‐polymer nanotubes may improve the long‐term function of neural microelectrodes.     

Fe(Ⅵ/Ⅲ)薄膜电极制备条件的影响及电化学性能研究

采用电沉积法制备了Fe(Ⅵ/Ⅲ)薄膜电极,研究了制备条件的影响及其电化学性能.利用SEM、AES、循环伏安及恒流充放电等测试手段分析了Fe(Ⅵ/Ⅲ)薄膜的微观形貌及其电化学性能.结果表明,Fe(Ⅵ/Ⅲ)薄膜上有微小的针状颗粒;Fe(Ⅵ/Ⅲ)薄膜电极具有电化学活性,可以进行锂离子的嵌入与脱出;Fe(Ⅵ/Ⅲ)薄膜电极表现出初次充放电的高容量和高放电平台,初次循环后充放电容量运渐降低并稳定在一个相对低的数值.     

碳布/聚吡咯储能包装膜材料的制备及表征

目的以甲壳素纳米纤维、多壁碳纳米管、碳布、吡咯为原料,制备柔性超级电容器复合电极薄膜。方法先利用化学氧化法提高碳布的表面粗糙度,再通过真空抽滤在碳布表面附着甲壳素纳米纤维和多壁碳纳米管,以增加碳布的负载空间,最后通过原位聚合吡咯来增加复合薄膜的电容性能。同时制备氧化碳布/聚吡咯复合薄膜作为对照组。结果制成的氧化碳布/甲壳素纳米纤维/多壁碳纳米管/聚吡咯复合薄膜在扫描速率为5 mV/s时,质量比电容达到了307 F/g,是氧化碳布/聚吡咯质量比电容(175 F/g)的1.75倍;在电流密度为2 A/g时,经过2000次循环后电容保留率为72.3%,库仑效率为73.8%。结论制备的氧化碳布/甲壳素纳米纤维/多壁碳纳米管/聚吡咯薄膜具有较高的比电容和循环稳定性,可以作为超级电容器电极材料应用于物联网行业的有源储能包装。     

MEMS超级电容器膜电极材料的表面改性

为了改善MEMS超级电容器膜电极的致密性,通过在聚吡咯(PPy)中引入苯磺酸钠(BSNa)和氧化石墨烯(GO)表面改性功能薄膜,实现聚吡咯薄膜在MEMS超级电容器三维微结构上的均匀沉积.借助扫描电镜(SEM)、循环伏安测试(CV)、交流阻抗谱测试(EIS)、恒流充放电测试(CP)等手段对表面改性后的样品进行电化学性能测试.结果表明:当吡咯单体(Py)与BSNa摩尔比为1∶2,GO含量为0.4%时,在-0.4~1.0 V电压范围内,以100 m V/s速率扫描56圈,PPy薄膜的致密性最佳;表面改性可以在很大程度上减轻PPy颗粒的团聚,使得聚合后的PPy分子链排布紧密,形成了规整的网状立体结构;在放电电流为2 m A时,比容量可以达到13.3 m F/cm2,MEMS超级电容器的电化学性能得到改善.     

The electrochemical synthesis of poly(pyrrole-co-o-anisidine) on 3102 aluminum alloy and its corrosion protection properties

The electrochemical syntheses of polypyrrole (PPy) and poly(pyrrole-co-o-anisidine) were achieved on 3102 aluminum alloy (Al) from 0.1 M monomer (pyrrole:o-anisidine, 8:2) containing 0.4 M oxalic acid solution using the cyclic voltammetry technique. The synthesized films were characterized by FT-IR spectroscopy. The thermal stability of films was determined by thermogravimetric analysis (TGA) technique. Surface morphologies were characterized by scanning electron microscope (SEM) images. The potential of zero charge (pzc) of Al was determined using electrochemical impedance spectroscopy (EIS). The corrosion behavior of samples was investigated with open circuit potential (E_ocp)–time, EIS, and anodic polarization techniques. It was found that copolymer coated Al provides better barrier property against of corrosion in 3.5% NaCl solution.