聚(3,4-亚乙基二氧噻吩)/聚(苯乙烯磺酸盐)高导电柔性薄膜制备及掺杂效应研究

目的 针对聚(3,4-亚乙基二氧噻吩)/聚(苯乙烯磺酸盐)(PEDOT:PSS)薄膜的电导率低的问题，采用二次掺杂方法，提高薄膜电导率和品质因数(FoM)，为制备可打印导电薄膜以及柔性光电器件表面导电层提供技术支撑。方法 采用多种无机酸分别与PEDOT:PSS溶液共混的掺杂方法，通过旋涂法在基底上制备透明导电薄膜。利用四点探针法、分光光度计测试系统，对掺杂处理后薄膜的方块电阻、透光率、导电率和品质因数进行测试及分析。利用原子力显微镜(AFM)、X射线光电子能谱(XPS)和霍尔效应测试系统，对薄膜内部结构进行有理分析，总结提升薄膜电导率的原因。结果 无机酸对薄膜电导率具有提升作用，通过硫酸的掺杂作用后，电导率可以由0.9 S/cm提高到2 216 S/cm，FoM从0.03提高到33;通过焦磷酸掺杂处理后的薄膜，电导率可以提高到1 623 S/cm，FoM提高到40。结论 掺杂试剂的沸点、解离常数、退火温度以及共混液的黏度都会影响薄膜的光电性能。解离常数越低，更容易解离出氢离子的掺杂试剂，能够与PSS结合形成PSSH，促进PEDOT和PSS分离。沸点低和解离常数小的无机酸掺杂试剂，能够有效提高薄膜的电导率，并能够获得高品质因数的薄膜。PEDOT:PSS通过无机酸改性处理后，减小了PEDOT和PSS之间作用力的同时，提高了薄膜内部PEDOT的相对含量，使PEDOT链变得线性，促进载流子传输，从而使薄膜的电导率提高。     

掺硼和掺磷的氢化纳米硅薄膜及其应用于类叠层太阳电池的研究

采用射频等离子体增强化学气相沉积法,制备了掺硼和掺磷的氢化纳米硅薄膜(nc-Si∶H),并将其应用于纳米硅薄膜类叠层太阳电池中。分析了薄膜样品的光学性能及表面形貌,结果表明:P型掺硼纳米硅薄膜的光学带隙为2.189 eV,电导率为8.01 S/cm,霍尔迁移率为0.521 cm2/(V.S),载流子浓度为9.61×1019/cm3;N型掺磷纳米硅薄膜的光学带隙为1.994 eV,电导率为1.93 S/cm,霍尔迁移率为1.694 cm2/(V.S),载流子浓度为7.113×1018/cm3;两者的晶粒尺寸都在3～5 nm之间,晶态比都在35%～45%之间,并且颗粒沉积紧密,大小比较均匀。制备了大小为20 mm×20 mm,结构为Al/AZO/p-nc-Si∶H/i-nc-Si∶H/n-nc-Si∶H/p-nc-Si∶H/i-nc-Si∶H/n-c-Si/Al背电极的纳米硅薄膜类叠层太阳电池,通过I-V曲线测试,其VOC达到544.3 mV,ISC达到85.6 mA,填充因子为65.7%。     

纳米SiO_2复合聚电解质的制备及电化学性能

以聚环氧乙烷/高氯酸锂络合物(PEO/LiClO4)为基体,前驱体正硅酸乙酯(TEOS)在基体中水解缩合原位生成纳米SiO2,制备了PEO/LiClO4/SiO2复合聚电解质膜,采用AFM、DSC和交流阻抗等方法研究了聚电解质膜的表面形貌、热性能和离子电导率。结果表明,原位生成的纳米SiO2粒子,均匀分散于PEO基体中。复合纳米SiO2后聚电解质膜的玻璃化转变温度和结晶度均降低。聚电解质膜的离子导电行为满足Arrhenius方程,并在10%SiO2含量时体系的电导率出现最大值2.6×10-5S/cm(30℃)。以此膜为电解质组装的全固态聚合物锂电池放电电压平稳,初始放电比容量为115mAh·g-1,40次循环后放电容量保持在92mAh·g-1。     

多孔钛/TiO2纳米管复合薄膜制备及其电化学性能

目的 制备高比容量多孔钛/TiO2纳米管三维自支撑一体化复合电极材料。方法 采用非溶剂致相分离法与高温烧结相结合的方法制备出孔径小、空间利用率高的三维多孔钛平板膜,然后经阳极氧化法在其表面生长TiO2纳米管,从而制备出多孔钛/TiO2纳米管复合薄膜电极。结果 以3 μm粒径钛粉为原料,N-甲基-2-吡咯烷酮、聚乙烯吡咯烷酮、聚丙烯腈为添加剂制备钛膜生坯,经刮膜成型后,在氩气保护下经1000 ℃烧结,得到孔径约为2～6 μm的多孔钛平板膜。采用阳极氧化法在多孔钛平板膜上直接生长TiO2纳米管,制得多孔钛/TiO2纳米管复合薄膜电极。该复合薄膜电极在超级电容器中具有良好的电化学性能,其在2 mA/cm2电流密度下,比电容为385.34 mF/cm2,即使电流密度增加到10 mA/cm2,比电容仍能保持在125.14 mF/cm2。结论 相较于TiO2纳米颗粒,采用此方法制备的多孔钛/TiO2纳米管复合薄膜电极具有良好的电化学性能,可为下一代储能器件提供新的思路。     

石墨烯引导LiFePO_4纳米片的一步溶剂热反应制备及其电化学性能

针对本征低的电子导电率和锂离子迁移速率导致LiFePO_4较差的电化学性能,以石墨烯作为模板,采用一步溶剂热法制备梭形结构的LiFePO_4/石墨烯(LFP/G)复合正极材料;采用XRD和SEM等表征复合正极材料的物相结构和微观形貌,微米级梭型LiFePO_4颗粒是由平均厚度约为55 nm的纳米薄片堆叠而成。电化学性能研究结果表明:在0.1C倍率下,LFP/G复合正极材料的初始可逆比容量可达153.2 mA·h/g,高于相同条件下LiFePO_4的;在10C倍率下充放电时,LFP/G表现出高达85.9m A·h/g的可逆比容量,远高于LiFePO_4的可逆比容量(56.3m A·h/g),展现出明显增强的电化学倍率性能。     

碳钢表面导电PEDOT涂层的电化学制备及防腐性能

目的 在Q235钢基底上电沉积致密导电聚合物PEDOT涂层，利用PEDOT的良好导电性，避免电荷集中，提高Q235钢的防腐性能。方法 在十二烷基硫酸钠（SDS）和高氯酸锂（LiClO4）溶液中，通过电化学恒电流方法在Q235碳钢基底上电聚合EDOT。采用循环极化、开路电位监测（OCP）、电化学阻抗谱（EIS）及扫描振动电极（SVET）等手段，研究导电PEDOT涂层与碳钢基底的电化学交互作用及其对基底腐蚀行为的影响规律。结果 在电流密度为5 mA/cm2的条件下，沉积的PEDOT涂层最完整、致密，具有球状团聚表面形貌。PEDOT/Q235电极在3.5%NaCl溶液中浸泡40 h后电偶电流密度为-15 μA/cm2，电偶电压为-715 mV。多次循环极化曲线基本重合，体现出良好的电化学稳定性。开路电位和EIS结果表明，PEDOT涂层4 d后钝化了基底，对基底产生保护。SVET结果证明，PEDOT涂层能够形成电子离域，避免电荷集中，涂层划痕区的电流密度从628 μA/cm2降低到23.8 μA/cm2。结论 PEDOT涂层可以减轻Q235基底在NaCl溶液中的腐蚀，其减缓腐蚀的能力归因于其结构致密、钝化基底及减少表面电荷集中。     

共溅射制备a-Si-Ag薄膜及其电化学储氢性能

氢化非晶硅(a-Si:H)薄膜因其具有很高的电化学储氢容量而在质子型电池中极具研究和应用价值，但其电化学循环稳定性较差的问题已然成为其商业化应用的最大阻碍。为了改善a-Si薄膜的导电性和力学性能以提高a-Si薄膜电极的电化学容量和循环寿命，通过磁控共溅射技术制备了具有不同Ag含量的复相Si-Ag薄膜，研究了高导电性金属Ag对a-Si薄膜电极在质子型离子液体中电化学储氢性能的影响。结果表明，在磁控溅射制备的Si-Ag薄膜中，Ag以单质纳米晶颗粒的形式弥散分布在非晶态a-Si基体中；复相Si-Ag薄膜的导电性能和电化学储氢性能均优于a-Si薄膜电极，其中Ag原子分数为20%时的Si-Ag薄膜电极具有高达887.7 mAh·g^-1的电化学容量，经100次充放电循环后其容量保持率S₁₀₀为64.23%。Ag纳米颗粒的引入可以有效缓解Si-Ag薄膜充放电过程中的体积效应，改善了薄膜电极的循环性能。     

锂硫电池用气相生长碳纤维增强硫-多壁碳纳米管复合正极的影响(英文)

制备了锂硫电池用硫-多壁碳纳米管纳米复合材料,并分别采用气相生长碳纤维(VGCFs)和导电炭黑作为复合正极的导电添加剂,通过形貌表征(SEM)、恒流充放电测试和交流阻抗分析(EIS)研究VGCFs对硫-多壁碳纳米管复合正极的影响。结果表明:采用VGCFs作添加剂的硫-多壁碳纳米管复合电极具有三维网状结构,其首次放电比容量为1254 mA·h/g,40次循环后容量保持在716 mA·h/g。与采用导电炭黑为添加剂的电极相比,采用VGCFs为添加剂的电极具有更高的活性物质利用率和更好的循环稳定性。相互搭接的纤维状VGCFs可形成稳定的导电网络,抑制正极材料及残存放电产物的团聚堆积,维持电极的多孔性,从而改善电池的电化学性能。     

电化学和水解-缩合方法制备具有防腐蚀和活化铜表面的多功能聚合纳米薄膜（英文）

通过恒电流技术和水解-缩合方法,在铜表面制备均三嗪二硫醇硅烷单钠盐多功能聚合纳米薄膜,该纳米薄膜能够防腐蚀和活化铜表面。采用电化学测试来评价该薄膜的防腐蚀性能;用傅里叶变换红外光谱学(FT-IR)和接触角技术监测纳米薄膜表面功能团的变化;用X射线光电子能谱(XPS)及扫描电子显微镜(SEM)分别研究聚合纳米薄膜的化学组成和形貌特征。结果表明:在整个制备过程,电化学聚合形成的二硫单元优先保护铜表面;紧接的水解(缩合)作用使得该薄膜形成新的、具有防腐蚀和活化铜的多功能聚合纳米薄膜。该界面(聚合纳米薄膜)使得其他含有羟基的化合物可能在铜表面键合,且能够应用在高要求的研究和工业中。     

氧化镍柔性自支撑电极材料的电化学性能研究

制备具有优异界面结构和电子/离子传质能力的柔性电极材料是解决高性能电化学活性物质由体积膨胀引起材料粉化和从集流体剥落难题的关键。一种独特的工艺实现了高性能过渡金属氧化物（氧化镍）内嵌碳纤维柔性织物电极的一步制备,所制备的活性物质免于使用导电剂、粘结剂和集流体直接用于锂离子电池负极材料的组装。得益于氧化镍超高的理论比容量,活性碳纤维基体材料低维特性和良好的内应力分散率,制备的复合织物电极展现出良好的电化学性能,一维氧化镍/碳纳米纤维（NiO-CNF）复合柔性电极较纯氧化镍（NiO NF）纤维电极材料具有更卓越的循环耐久性和倍率性能,NiO-CNF和NiO NF在0.5C倍率循环200次分别具有418 mAh·g-1和242 mAh·g-1的可逆容量,良好的电化学性质归因于复合柔性电极的交联结构提供的优异扩散动力学和应力缓冲。     

石墨烯/银纳米复合材料的制备及抗菌性能研究

采用改进的Hummers法制备氧化石墨(GO),加入一定量的聚乙烯亚胺和硝酸银(PEI-Ag+)配位复合物,通过自组装法组装,利用硼氢化钠的还原性,制备石墨烯/银纳米复合材料。用紫外可见吸收光谱(UV-Vis)、红外吸收光谱(FT-IR)、X射线衍射(XRD)、循环伏安法(CV)、扫描电镜(SEM)、拉曼光谱(Raman)等手段对所制备的石墨烯/银纳米复合材料进行表征。以金黄色葡萄球菌和大肠杆菌为模型对纳米复合材料的抗菌性能进行研究。结果表明:银纳米粒子负载在石墨烯表面形成石墨烯/银纳米复合物材料,石墨烯/银纳米复合材料对金黄色葡萄球菌和大肠杆菌生长具有较好的抑制作用,且抗菌性能稳定。当石墨烯/银纳米复合材料浓度为4和15 mg/m L时,分别对金黄色葡萄球菌和大肠杆菌的抑菌效果好。     

Vapor phase polymerization of poly (3,4-ethylenedioxythiophene) on flexible substrates for enhanced transparent electrodes

Recently, conducting polymer thin films have been investigated as transparent electrodes in photovoltaic devices and organic light emitting diodes. Due to its relatively high conductivity and excellent transmission in the visible region, poly (3, 4-ethyelenedioxythiophene) (PEDOT) has been shown to be a viable option for such applications. Herein described is a method for the vapor phase polymerization (VPP) of transparent PEDOT thin film electrodes on flexible polyethylene naphthalate (PEN) substrates and the comparison of this VPP method with two current approaches to PEDOT deposition: solution-based in situ polymerization and spin coating a dispersion of PEDOT:PSS. Electrical conductivities and UV–vis transmittances were measured for films produced by each of these methods, with VPP PEDOT showing both the highest conductivity (approx. 600 S/cm) and transmittance (>94% at 550 nm). The surface morphologies of the films were compared using AFM and SEM imaging. The stability of these PEDOT films, stored under ambient conditions, was investigated by monitoring the conductivity and transmittance of the thin films over time.     

Electrochromic, magnetotransport and AC transport properties of vapor phase polymerized PEDOT (VPP PEDOT)

Poly(3,4-ethylenedioxy)thiophene (PEDOT) doped with tosylate ion (PEDOT–tosylate or VPP PEDOT) was synthesized by vapor phase polymerization (VPP) technique on glass as well as on glass/ITO and the electrochromic properties were investigated. Compared with that of PEDOT–PSS spin-coated on glass/ITO, the studies showed that VPP PEDOT has a lower work function and better electrochromic properties. The magneto and AC transport properties studies were done on VPP PEDOT coated on glass substrate. The system shows 2-dimensional variable range hopping and wave function shrinkage of charge carriers.     

Influence of Ag doped graphene on electrochemical behaviors and specific capacitance of polypyrrole-based nanocomposites

In this work, silver (Ag) nanoparticles were deposited on graphene sheets by chemical reduction and Ag-doped graphene (Ag-GR)/polypyrrole (PPy) nanocomposites were prepared by oxidation polymerization. The effect of the Ag-GR incorporation on the electrochemical properties of the PPy nanocomposites was investigated. It was found that highly dispersed Ag nanoparticles (2–5 nm) could be deposited onto the GR and that Ag-GR was successfully coated by PPy. From the cyclic voltammograms, Ag-GR showed higher electrocatalytic activity than that of pristine GR. Furthermore, the Ag-GR/PPy showed remarkably increased current density, quicker response, and better specific capacitance compared with GR/PPy. This indicates that, due to their high electrocatalytic activity, the Ag nanoparticles deposited onto the GR serve as an efficiency catalyst to improve electrochemical performance of the GR/PPy and that they resulted in the increase of the charge transfer between GR and PPy by bridge effect.     

Effects of the FeCl<Subscript>3</Subscript> concentration on the polymerization of conductive poly(3,4-ethylenedioxythiophene) thin films on (3-aminopropyl) trimethoxysilane monolayer-coated SiO<Subscript>2</Subscript> surfaces

This study examined the effects of the FeCl₃ (oxidant) concentration on the vapor phase polymerization (VPP) of conducting poly (3,4-ethylenedioxythiophene) (PEDOT) thin films on (3-aminopropyl)trimethoxysilane (APS)-coated SiO₂ surfaces, in which the interaction between Fe(III) and the -NH₂ groups of APS enabled a uniform distribution of FeCl₃ on the surface. The FeCl₃ concentration has a strong impact on the thickness, surface morphology, and conductivity of the PEDOT films deposited by VPP on an APS monolayer. The thickness of the PEDOT thin films increased linearly as the FeCl₃ concentration increased, as predicted by a model of spun films from a FeCl₃ solution. However, the rate of the increase in PEDOT thin film thickness per unit of FeCl₃ in wt.% was lower than the predicted value. This suggests that the consumption of FeCl₃ not participating in polymerization to produce Fe₂O₃ or FeCl₃ aggregates increased as the FeCl₃ concentration increased. In addition, the surface morphology improved as the FeCl₃ concentration increased from 1 wt.% to 3 wt.% and the conductivity increased to approximately 400 S/cm. However, further increases in the FeCl₃ concentration to 5 wt.% and 7 wt.% significantly degraded the morphology by creating holes in the PEDOT film, which reduced the conductivity.     

N掺杂石墨化纳米金刚石超级电容器电极材料性能

为探索制备高能量密度和高循环性能的超级电容器材料,将三聚氰胺与石墨化纳米金刚石(graphitized nano diamond,GND)混合物在N₂气氛中高温处理,制备表面N掺杂吸附的核壳纳米复合粒子(nitrogen doped GND,N-GND)。由拉曼光谱和X射线衍射分析可知:N原子掺入石墨层中,在一定程度上增加其缺陷, 且不改变其晶体结构。由透射电镜分析可知:N掺杂引起GND周围石墨层出现蜷曲形状。对N-GND粉末电极进行电化学性能测试,结果表明:在扫速为5 mV/s时,电极比电容高达206.7 F/g;在对称两电极体系下的恒流充放电测试中,在电流密度为0.4 A/g时,N-GND的比电容达到198.7 F/g;在50 mV/s的扫描速度下,经2 000圈循环伏安测试后,比电容仅衰减4.23%,表现出优异的循环稳定性。以N-GND作为新型超级电容器电极材料,掺杂吸附的石墨壳层赋予其良好的导电性,GND芯部具有高热稳定性及化学稳定性,可避免传统石墨烯叠聚问题并构造可控的介孔通道,同时N掺杂吸附可提高其电容性能。      

New application and electrochemical characterization of a nickel-doped mesoporous carbon for supercapacitors

A novel electrode of nickel-doped mesoporous carbon (NMC) is prepared from furfuryl alcohol and firstly developed for use in electrochemical capacitors. The electrochemical performance of NMC/AC capacitor is systematically investigated and characterized by BET and BJH methods for determining surface area and pore size distribution, respectively. This new NMC/AC shows a high specific capacitance, high energy and power density due to its large surface area and bulk conductivity. Its electrochemical characteristics are investigated through cyclic voltammetry (CV), electrochemical impedance spectroscopy and charge-discharge (C/D) tests. The NMC/AC has a specific capacitance of 144.3 Fg⁻¹, higher than that of a pure activated carbon (AC)-based EDLC (ca. 105 Fg⁻¹). It can be a promising candidate for a new energy storage material for supercapacitor.     

激光烧结石墨烯钛纳米复合材料及其耐腐蚀性能

石墨烯增强钛基纳米复合材料,因其良好的力学性能有望成为轻质高强结构材料。为了研究其硬度和耐腐蚀性能,在AISI 4140 合金结构钢的基板上采用激光烧结的方法制备了石墨烯钛纳米复合材料。采用扫描电子显微镜、X射线衍射仪、显微硬度计、拉曼光谱仪等研究了其微观结构、相组成和显微硬度等,并采用电化学极化法研究了激光烧结石墨烯钛纳米复合材料和纯钛在3.5%NaCl溶液中的腐蚀行为。结果表明：激光烧结后石墨烯存在并均匀分散于钛基纳米复合材料中,石墨烯的添加使得钛基纳米复合材料的显微硬度达到了450 HV0.2,与激光烧结纯钛（180 HV0.2）相比提高了1.5倍。石墨烯钛纳米复合材料的腐蚀电位比激光烧结纯钛的腐蚀电位有明显提高,从-0.64 V提高到-0.59 V;同时,腐蚀电流从1.6×107 A/cm2降低到7×108 A/cm2,说明其耐腐蚀性能优于激光烧结纯钛。     

氧化石墨烯化学接枝提高纳米银的负载效果

目的 分别使用酰氯法和氨基开环法接枝修饰氧化石墨烯(GO),利用接枝分子的"锚定效应"提高纳米银颗粒在GO表面的分散效果.方法 先对GO-Cl-DA(GO经酰氯化后接枝对苯二胺)和GO-DA(采用"一锅法"对GO和对苯二胺直接混合接枝)进行比较,之后又比较了先接枝后沉积纳米粒子(两步法)和接枝/沉积同时进行(一步法)得到的杂化材料.采用红外光谱、X射线衍射谱、X射线光电子能谱和热失重曲线等,分析了材料的组成、热稳定性、接枝方式、银纳米颗粒的负载效果等.结果 在氨基与环氧基开环反应或酰胺键的作用下,对苯二胺分子能有效地接枝在GO表面,其中,"一锅法"(即氨基开环法)的接枝效率较高,操作简便.在沉积银的过程中,两步法对基底还原程度更彻底,纳米银的负载量从一步法的1.01％(原子数分数)提高到了7.22％,且分散性更好,并由此提出了接枝小分子对纳米颗粒的锚定效应.结论 含有氨基的分子对氧化石墨烯进行修饰时,采用氨基开环法既简单,又高效,接枝分子通过锚定效应改善原位沉积的无机纳米粒子,可获得负载效果优异的杂化材料.     

石墨烯/纳米金刚石复合电极性能研究

为开发具有高能量密度、高功率密度和长寿命的超级电容器复合电极,将纳米金刚石(nano diamond,ND)经真空热处理获得石墨化纳米金刚石(graphitized nano diamond,GND),再采用超声法将不同质量比的石墨烯与GND制备成复合电极,进行电化学性能测试并分析其结构。电化学性能测试结果表明:质量比为4∶1时制备的石墨烯/GND复合电极具有良好的双层电容特性,其循环伏安曲线近似呈矩形且形状几乎不随扫描速率变化而改变。在扫描速率为2 mV/s,电解液为0.5 mol/L的K₂SO₄溶液的条件下,其比电容高达103.3 F/g;经循环扫描1000圈后,比电容衰减幅度不到0.95%,具有优异的循环稳定性。经透射电镜分析可知:真空高温处理后ND表面形成石墨烯层;受金刚石结构的制约,石墨烯层间距由内向外逐渐增加,提高了复合电极的导电性。由扫描电镜形貌表征可知:GND均匀附着在石墨烯表面,在石墨烯的片层之间形成阻断,防止石墨烯的杂乱堆叠,有利于电解液的扩散,从而使复合材料的比电容增大、电化学性能提高。