化学氧化法聚吡咯导电性能与导电机理

采用化学氧化法制备了导电聚吡咯(PPy).运用SEM和TEM表征了PPy的形貌,利用四探针技术测试了材料的电导率,对影响其电导率的因素进行了讨论,并对其导电机理进行研究.结果表明,氧化剂用量、反应温度、反应时间、掺杂剂的种类等对最终所得材料的导电性能及结构形态有较大的影响.以苯磺酸钠作掺杂剂,FeCl3/Py摩尔比为1.0,冰浴条件下,反应0.5h所得材料电导率最高,为58.82S/cm,其中以2-萘磺酸为掺杂剂所得PPy微观形貌呈现罕见的纤维状.电导率相对较高的PPy,说明其本身掺杂状况使它在氧化掺杂时随导带和价带间的能级差减小,禁带变窄,载流子移动阻力小;阴离子的掺杂和脱掺杂变得容易,因而电导率高.     

化学氧化法聚吡咯导电性能与导电机理

采用化学氧化法制备了导电聚吡咯(PPy).运用SEM和TEM表征了PPy的形貌,利用四探针技术测试了材料的电导率,对影响其电导率的因素进行了讨论,并对其导电机理进行研究.结果表明,氧化剂用量、反应温度、反应时间、掺杂剂的种类等对最终所得材料的导电性能及结构形态有较大的影响.以苯磺酸钠作掺杂剂,FeCl3/Py摩尔比为1.0,冰浴条件下,反应0.5h所得材料电导率最高,为58.82S/cm,其中以2-萘磺酸为掺杂剂所得PPy微观形貌呈现罕见的纤维状.电导率相对较高的PPy,说明其本身掺杂状况使它在氧化掺杂时随导带和价带间的能级差减小,禁带变窄,载流子移动阻力小;阴离子的掺杂和脱掺杂变得容易,因而电导率高.     

掺杂聚乙烯咔唑的有机二极管的伏安特性

本文提出了一种掺杂具有空穴导电特性的聚合物来改变有机二极管伏安特性的新方法。在导电玻璃上利用甩胶法分别制得两粗有机薄膜层：聚烷基噻吩和掺杂不同量聚乙烯咔唑的聚烷基噻吩。将铝沉积在这些有机薄膜上作为有二极管的负极。     

新型导电高聚物对神经元修补元件的表面改性

利用一种新型的导电聚合物——聚3,4-二氧化乙烷噻吩(PEDOT)的衍生物PEDTM,成功地在用微加工技术制作的神经元修补元件的电极上制得了导电涂层。该导电聚合物既克服了聚吡咯由于α—β(β?键接而产生的缺陷, 又克服了EDOT在水中溶解度小,无法在生物分子的掺杂下电化学合成PEDOT/生物分子导电涂层的缺陷。SEM和AFM照片表明PEDTM/PSS导电涂层具有粗糙的表面形貌,表面积增加,其阻抗也比未涂层前降低很多,在1 kHz处其阻抗值降低了两个数量级。研究结果表明,PEDTM/生物分子导电涂层的阻抗比聚吡咯/生物分子涂层降低得更多。     

聚(3,4-乙撑二氧噻吩)的二次掺杂改性研究

利用乙二醇(EG)对聚(3,4-乙撑二氧噻吩)(PEDOT)进行二次掺杂改性,考察了二次掺杂PEDOT薄膜的电学性能、表面形貌和分子组成,并且对PEDOT的二次掺杂改性机理进行了探讨.研究发现,未进行二次掺杂时,PEDOT导电颗粒因被绝缘的聚苯磺酸(PSS)包埋而不能彼此接触,电荷在PEDOT薄膜中的传导由隧道效应占主导,薄膜的电导率较低.二次掺杂后,PEDOT与PSS发生相分离,同时PSS的相对含量降低,PEDOT导电颗粒问形成导电通道,薄膜的电导率较高.     

导电高分子聚合物电化学修饰电极

运用循环伏安法分别在0.15M吡咯(py)+0.1M氯化钾(Kcl)溶液的对氨基苯甲酸中(PAPB)和水中,在不锈钢(SS)表面制备聚吡咯(Ppy)薄膜。用循环伏安法与恒定电位法(恒电位1.5V),测试工作电极的稳定性与导电性。结果表明,单独在不锈钢表面附着聚吡咯薄膜(Ppy/SS),虽可以增强工作电极的稳定性,但工作电极的导电性减弱。而掺杂了对氨基苯甲酸的聚吡咯膜(Ppy/PAPB),能提高不锈钢复合电极的稳定性。同时,可以弥补合成单一薄膜导电性能减弱的缺点。从而将稳定性与导电性很好的结合。     

自组装法合成导电聚吡咯纳米线

以多孔氧化铝为模板,合成导电聚吡咯纳米线。利用SEM对聚吡咯进行了表征,结果表明:在吡咯单体浓度为0.2 mol/L,电压1.0 V,时间1 600 s的条件下,制得的聚吡咯会有大量的微触手结构出现,且表面光滑,比表面积较大,并初步探究了聚吡咯微触手结构的形成机理。     

形貌对LiFePO_4性能影响的研究进展

综述了近年来新型锂离子电池正极材料LiFePO4的研究进展。从掺杂网状结构碳、碳纳米管、碳纳米纤维以及球形、棒状和空心LiFePO4的制备几个方面,对不同形貌与结构的LiFePO4的研究现状进行了介绍与讨论。碳掺杂可有效提高LiFePO4的导电性,并抑制粒径的增大;减小材料颗粒的粒径,可以从根本上提高颗粒的比表面积,有效减小电荷的移动距离,提高参与电化学反应材料的比例;而材料的特殊形貌有助于形成导电网络,对其导电性能的提高有着十分重要的影响。综上所述,通过减小颗粒的粒径、提高比表面积、掺杂导电剂以及制备更易形成导电网络形貌的材料,是获得优良性能LiFePO4的有效方法。     

应用聚吡咯电解质的固体钽电解电容器

叙述了聚吡咯电解质的制备过程,并比较了该电解质较传统电解质的特点,分析了聚吡咯电解质固体钽电解电容器的性能特征。应用PPy-DEHS(2-(2-乙基己基)硫代丁二酸钠盐掺杂聚吡咯,溶剂为三氟乙酸)电解质装配的固体钽电解电容器具有较高的电容量和较低的损耗。在掺杂聚吡咯中加入表面活性剂和偶联剂可以增加电容器容量,降低其损耗。     

高频低阻抗片式固体电解电容器的进展

为降低片式固体电解电容器的等效串联电阻从而改善电容器阻抗－频率特性，国外采用了导电功能高分子材料聚吡咯作电解质，代替原用的ＭｎＯ２、有机半导体ＴＣＮＱ取得显著效果，国内已开展了导电聚吡咯的应用研究。     

The effect of growth rate variation on the conductivity and morphology of polypyrrole thin films

This study reports the growth conditions and resulting surface and electrical properties of BF_-4 doped polypyrrole films for possible electronic device applications. Growth rate has been observed to significantly affect both the conductivity and morphology of the polypyrrole films grown by a constant current electrochemical polymerization technique. A peak in the conductivity occurs at a growth current density of 0.75 mA/cm² (anode voltage of 0.54 V) coincident with a break in the linearity of the current density-anode voltage plot suggesting a possible change in reaction kinetics. Surface morphology also showed a strong dependence on film thickness as well as growth rate. Electronic conductivities in excess of 200 (Ω-cm)¹ have been obtained but tend to deteriorate with time. Thin films are most affected showing a conductivity decrease of three orders of magnitude in two months, and results suggest changes are limited to the top 1–2 μm of the film.     

非掺锑化镓抛光工艺研究

分析了非掺锑化镓单晶片的化学抛光机制和影响获得表面质量良好的非掺锑化镓单晶片的因素，得到了非掺锑化镓的抛光工艺参数。利用该工艺可以制备表面光洁、平整、无缺陷的非掺锑化镓单晶抛光片。     

Self‐Compensation in Transparent Conducting F‐Doped SnO2

The factors limiting the conductivity of fluorine‐doped tin dioxide (FTO) produced via atmospheric pressure chemical vapor deposition are investigated. Modeling of the transport properties indicates that the measured Hall effect mobilities are far below the theoretical ionized impurity scattering limit. Significant compensation of donors by acceptors is present with a compensation ratio of 0.5, indicating that for every two donors there is approximately one acceptor. Hybrid density functional theory calculations of defect and impurity formation energies indicate the most probable acceptor‐type defects. The fluorine interstitial defect has the lowest formation energy in the degenerate regime of FTO. Fluorine interstitials act as singly charged acceptors at the high Fermi levels corresponding to degenerately n‐type films. X‐ray photoemission spectroscopy of the fluorine impurities is consistent with the presence of substitutional F_O donors and interstitial F_i in a roughly 2:1 ratio in agreement with the compensation ratio indicated by the transport modeling. Quantitative analysis through Hall effect, X‐ray photoemission spectroscopy, and calibrated secondary ion mass spectrometry further supports the presence of compensating fluorine‐related defects.     

低团聚掺锑氧化锡纳米微粉的制备

以SnCl4?5H2O和SbCl3乙醇溶液为原料,用阴离子树脂交换除氯水解法制得无Cl–的掺锑氢氧化锡胶体沉淀。并用乙酸异戊酯作脱水剂。结果表明,用乙酸异戊酯共沸蒸馏干燥法能有效防止粉体的硬团聚,得到了比表面积为284.43m2/g掺锑氢氧化锡微粉。热处理后得到了低硬团聚、电阻率为0.405?·cm的掺锑氧化锡纳米晶体。     

Functionally Antagonistic Hybrid Electrode with Hollow Tubular Graphene Mesh and Nitrogen‐Doped Crumpled Graphene for High‐Performance Ionic Soft Actuators

Ionic soft actuators, which exhibit large mechanical deformations under low electrical stimuli, are attracting attention in recent years with the advent of soft and wearable electronics. However, a key challenge for making high‐performance ionic soft actuators with large bending deformation and fast actuation speed is to develop a stretchable and flexible electrode having high electrical conductivity and electrochemical capacitance. Here, a functionally antagonistic hybrid electrode with hollow tubular graphene meshes and nitrogen‐doped crumpled graphene is newly reported for superior ionic soft actuators. Three‐dimensional network of hollow tubular graphene mesh provides high electrical conductivity and mechanically resilient functionality on whole electrode domain. On the contrary, nitrogen‐doped wrinkled graphene supplies ultrahigh capacitance and stretchability, which are indispensably required for improving electrochemical activity in ionic soft actuators. Present results show that the functionally antagonistic hybrid electrode greatly enhances the actuation performances of ionic soft actuators, resulting in much larger bending deformation up to 620%, ten times faster rise time and much lower phase delay in a broad range of input frequencies. This outstanding enhancement mostly attributes to exceptional properties and synergistic effects between hollow tubular graphene mesh and nitrogen‐doped crumpled graphene, which have functionally antagonistic roles in charge transfer and charge injection, respectively.     

Ar环境下氢化非晶锗硅的制备与特性研究

采用RF-PECVD法在氩环境下制备了Ge掺杂a-Si∶H.将样品通过台阶仪、傅里叶红外光谱仪、紫外可见光分光光度计以及Keithley高阻仪进行分析测试,研究了不同掺杂比例对非晶硅薄膜沉积速率、结构因子、光学带隙及光暗电导率的影响.实验表明:薄膜沉积速率随掺杂量的增大而增大;薄膜结构因子随掺杂量的增大而减小;薄膜对可见光的吸收随掺杂量的增大出现红移,光学带隙减小;掺杂比例较低时,薄膜光暗电导率变化不明显,当GeH4量达20 cm3/min时,薄膜暗电导明显增大,光暗电导比减小.     

Controlling the Optical,Electrical and Chemical Properties of Carbon Inverse Opal by Nitrogen Doping

Nitrogen‐doped carbon inverse opal (CIO‐N) is synthesized by a two‐step process involving the infiltration of carbon‐nitrogen precursors within opals followed by the thermolysis and removal of the opal structure in hydrofluoric acid (HF). Undoped samples exhibit a reflection peak in the red region of the spectrum whereas N‐doped samples display shifts to the blue region of the spectrum as the nitrogen content is increased. The degree of crystallinity of CIO‐N strongly depends upon the nitrogen content and on the size of the precursor silica particles used to prepare the inverted opals. In addition, the introduction of nitrogen into the samples is able to increase the electrical conductivity by one order of magnitude from 2 to 30 S cm^‐1 (at room temperature). All samples are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X‐ray diffraction (XRD), Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS), ultraviolet‐visible (UV‐Vis) spectroscopy, and electrical conductivity measurements. It is envisaged that CIO‐N could have important applications in the fabrication of photonic crystals, photoconducting materials, molecular sensors, field emission devices, capacitors, batteries, among many others.     

聚吡咯热稳定性的改善及其在电容器中的应用

采用化学聚合法合成了聚吡咯(PPy),并以此制作了固体铝电解电容器,研究了对硝基苯酚(p-NPh)的添加量对PPy的电导率及热稳定性的影响,以及与少量聚乙烯醇(PVA)复合后产物的性能变化。结果表明,在x(p-NPh)为0.15mol/L的条件下,聚合产物的电导率约为11.55S/cm,热稳定性最好。含质量分数5%PVA的复合物为絮状颗粒,以其制作的电容器的耐热性有较大改善,初始Res为28.1mΩ,经过150℃/1h处理之后为51.4mΩ。