氧化镝-聚苯胺复合涂料制备及防腐性能研究

采用乳液原位聚合法,合成十二烷基苯磺酸钠(SDBS)掺杂的聚苯胺(PANI).通过电导率分析和塔菲尔曲线(Tafel)等手段,表征了在一定的合成条件下,SDBS与苯胺(An)摩尔比(n(SDBS)/n(An))的改变及氧化镝(Dy2O3)的加入对PANI涂层防腐性能的影响.实验结果表明,PANI含量为25%、n(SDB...     

Co~(2+)掺杂聚苯胺复合薄膜的电化学合成及抗腐蚀性能的研究

在含有苯胺(PANI)、硝酸(HNO3)和硝酸钴[Co(NO3)2·6H2O]的溶液中,采用循环伏安法(CV)在不锈钢基底表面制备PANI/Co2+复合薄膜。利用傅里叶红外光谱(FT-IR)、X射线衍射(XRD)等手段对其结构和形貌进行表征。在0.5mol/L H2SO4中,通过循环伏安测试(CV)、交流阻抗(EIS)、塔菲尔(Tafel)曲线对PANI/Co2+复合薄膜的耐腐蚀性能进行了研究。结果表明,不锈钢表面覆盖掺杂态聚苯胺膜后,其腐蚀电位比纯聚苯胺膜时提高,可以显著降低腐蚀电流密度,并且Co2+浓度会影响掺杂态膜的耐腐蚀性。     

聚苯胺/纳米ZnO复合防腐涂层的制备及电化学性能研究

采用十二烷基硫酸钠(SDS)为乳化剂,过硫酸铵(APS)为氧化剂,利用微乳液聚合法合成聚苯胺/纳米ZnO的复合防腐材料,将其与环氧树脂共混得到新型的防腐涂料,并通过开路电位(OCP)和塔菲尔曲线(Tafe1)分析涂层的防腐性能。结果表明,含有纳米ZnO的聚苯胺复合涂料和单一聚苯胺涂料相比,显示了更好的防腐性能。     

聚苯胺/聚吡咯复合薄膜电极的制备及其超电容和耐腐蚀性

在聚苯胺(PANI)和聚吡咯(PPy)的相应单体溶液中,采用循环伏安法(CV)在不锈钢基体(SS)上分层聚合制备了具有聚苯胺/聚吡咯复合薄膜(PANI/PPy/SS)的电极材料。用傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)对其结构进行了表征。在0.5mol/L H2SO4中,对PANI/PPy/SS电极材料进行了循环伏安法、恒流充放电、交流阻抗谱(EIS)等电化学性能测试,并用塔菲尔曲线(Tafel)研究了其耐腐蚀性能。结果表明,当电流密度为5mA/cm2时,PANI/PPy/SS电极材料比电容达747.5F/g,且复合膜的腐蚀电位相对于单纯的PANI、PPy薄膜分别正移了0.064V、0.117V,表现出较好的耐腐蚀性,是一种应用前景很好的超级电容器材料。     

改性石墨烯/聚苯胺的制备及其环氧涂层的防腐蚀性能

为了改善环氧树脂防腐蚀涂料存在的孔洞缺陷,以改性石墨烯/聚苯胺复合材料作填料来提高环氧涂料的防腐蚀性能。首先采用改进的Hummers法制备了氧化石墨烯(GO),再利用对苯二胺还原GO得到改性石墨烯(PGO),进一步制备出改性石墨烯/聚苯胺(PGO/PANI)复合材料。通过拉曼光谱仪、场发射扫描电镜等研究了PGO/PANI的结构和微观形貌,利用盐雾试验、Tafel曲线和电化学阻抗谱研究了 PGO/PANI的防腐蚀性能。结果表明:PGO/PANI涂层的腐蚀等级由空白环氧涂层的10级提高到5级;PGO与PANI有良好的协同作用,PGO与苯胺单体质量比为0.10时,所制备的PGO/PANI复合涂层的防腐蚀效果较好,腐蚀电压为-194.59mV (vs SCE)、腐蚀电流密度为2.12×10^-9A/cm^2.     

纳米Al_2O_3溶胶复合水性聚苯胺环氧树脂涂层的制备及性能EI北大核心CSCD

以γ-缩水甘油醚氧丙基三甲氧基硅烷(GPTMS)为改性剂,对纳米氧化铝溶胶进行改性处理,随后将其分散于聚苯胺/水性环氧树脂中,再经固化剂固化,制成纳米氧化铝溶胶复合涂层。利用电化学交流阻抗、动电位极化曲线等手段分别对水性环氧涂层(epoxy)、纳米氧化铝溶胶改性水性环氧涂层(Al_2O_3/epoxy)、聚苯胺复合水性环氧涂层(PANI/epoxy)以及纳米氧化铝溶胶复合聚苯胺/水性环氧涂层(Al_2O_3/PANI/epoxy)的耐腐蚀性能和力学性能进行了研究。结果表明,Al_2O_3/PANI/epoxy涂层在3.5%NaCl溶液中浸泡15 d后的交流阻抗值为2.87×10~7Ω·cm^2,比epoxy涂层提高了3个数量级,防腐能力最强。该涂层的附着力为0级,硬度为6H,均高于其他涂层。另外,Al_2O_3/PANI/epoxy涂层的SEM照片显示,纳米Al_2O_3粒子与聚苯胺及环氧树脂粘连紧密,无明显的团聚。并发现在涂层与金属界面间出现了致密钝化层。     

纳米Al_2O_3溶胶复合水性聚苯胺环氧树脂涂层的制备及性能

以γ-缩水甘油醚氧丙基三甲氧基硅烷(GPTMS)为改性剂,对纳米氧化铝溶胶进行改性处理,随后将其分散于聚苯胺/水性环氧树脂中,再经固化剂固化,制成纳米氧化铝溶胶复合涂层。利用电化学交流阻抗、动电位极化曲线等手段分别对水性环氧涂层(epoxy)、纳米氧化铝溶胶改性水性环氧涂层(Al_2O_3/epoxy)、聚苯胺复合水性环氧涂层(PANI/epoxy)以及纳米氧化铝溶胶复合聚苯胺/水性环氧涂层(Al_2O_3/PANI/epoxy)的耐腐蚀性能和力学性能进行了研究。结果表明,Al_2O_3/PANI/epoxy涂层在3.5%NaCl溶液中浸泡15 d后的交流阻抗值为2.87×10~7Ω·cm~2,比epoxy涂层提高了3个数量级,防腐能力最强。该涂层的附着力为0级,硬度为6H,均高于其他涂层。另外,Al_2O_3/PANI/epoxy涂层的SEM照片显示,纳米Al_2O_3粒子与聚苯胺及环氧树脂粘连紧密,无明显的团聚。并发现在涂层与金属界面间出现了致密钝化层。     

水性聚苯胺/蒙脱土/丙烯酸乳液复合防腐蚀涂层研究

采用原位化学氧化聚合方法制备了聚苯胺/蒙脱土复合材料,并以丙烯酸乳液为成膜物,制备了水性聚苯胺/蒙脱土/丙烯酸乳液复合防腐蚀涂层材料。研究了蒙脱土与苯胺的配合比、聚苯胺/蒙脱土复合材料用量、磷酸浓度等对复合涂层防腐性能的影响。实验结果表明,苯胺/蒙脱土复合材料具有片层结构,聚苯胺/蒙脱土/丙烯酸乳液复合涂层对马口铁具有较好的防护效果,当蒙脱土与苯胺质量配合比为2∶10,聚苯胺/蒙脱土复合材料用量为0.10%(wt,质量分数),磷酸浓度为0.10mol/L时,制得的水性聚苯胺/蒙脱土/丙烯酸乳液复合防腐涂层,腐蚀电流为2.187×10~(-6) A/cm~2,极化电阻为14455.9Ω,复合涂层具有最佳的防腐性能。     

聚苯胺/凹凸棒石与磷钛粉协同型防腐蚀涂料的性能

传统的聚苯胺颗粒粗大,在涂料中分散性差,涂料制备成本高。以聚苯胺/凹凸棒石(PANI/ATP)与磷钛粉为防腐蚀填料,环氧树脂为成膜物质,制备了聚苯胺/凹凸棒石与磷钛粉(PAP-C)协同型防腐蚀涂料。通过电化学交流阻抗(EIS)和开路电位(OCP)对其涂层防腐蚀性能进行了表征,探讨了PANI/ATP用量、颜基比和分散剂用量对PAP-C涂层的力学性能和防腐蚀性能的影响。结果表明:PAP-C涂层较磷钛粉(P-C)涂层具有更好的防腐性能及更高的耐冲击强度;当PANI/ATP用量为4%,颜基比为1.00,分散剂用量为1.0%时,PAP-C涂层耐冲击强度50 cm,附着力1级,柔韧性2 mm,可耐中性盐水(3.5%Na Cl)腐蚀60 d。     

原位聚合法制备聚苯胺改性MoS2及其环氧复合涂层的防腐性能

为提高环氧涂料的防腐性能,本文引入MoS₂纳米片作为阻隔剂,并在MoS₂纳米片表面原位聚合聚苯胺(PANI),制备了夹层结构i-PANI@MoS₂纳米片,利用PANI提高涂层的导电性,达到阳极钝化的效果。研究发现,当PANI与MoS₂的摩尔配比增大到7∶1时,MoS₂片层表面被PANI均匀覆盖,改性效果最好。与环氧树脂复合后,i-PANI@MoS₂-7纳米片在环氧树脂中均匀分散,复合涂层导电率提高,PANI与MoS₂起到了协同防腐作用,此时i-PANI@MoS₂纳米片既作为涂层中的阻隔剂,又作为电化学腐蚀保护剂,因此复合涂层具有最大的阻抗值、最大腐蚀电压以及最小的腐蚀电流密度,防腐性能优异。但PANI与MoS₂配比进一步增大,MoS₂纳米片表面的聚苯胺会发生团聚,导致复合涂层的防腐性能下降。     

One-step synthesis of conductive graphene/polyaniline nanocomposites using sodium dodecylbenzenesulfonate: preparation and properties

The preparation of conducting graphene/polyaniline–sodium dodecylbenzenesulfonate (PANI–SDBS) nanocomposites using synthesised graphene as the starting material is successfully conducted in the present study. The effect of the anionic surfactant SDBS on the properties of the graphene/PANI–SDBS nanocomposites is studied. The structure and morphology of the synthesised nanocomposites are characterised by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, ultraviolet–visible (UV–vis) spectrophotometry, X-ray diffraction and atomic force microscopy (AFM). The electrical conductivity properties of the resulting nanocomposites are determined using a resistance meter measurement system. The FESEM and TEM images reveal that the addition of SDBS surfactant to the PANI transforms the nanofibers of the PANI to a nanosphere morphology of PANI–SDBS. FTIR and UV–vis studies reveal that the conductive graphene/PANI–SDBS nanocomposites are successfully synthesised. AFM characterisation shows that the addition of graphene reduces the root mean square roughness of the surface of the PANI. The electrical conductivity and thermal stability of the PANI are improved after the introduction of SDBS. The nanocomposites containing a 5 wt% graphene loading exhibit the highest electrical conductivity of 2.94?×?10^?2 S/cm, which is much higher than that of PANI (9.09?×?10^?6 S/cm).     

Fe_3O_4-ODA/GO/PANI复合材料的制备及其电容性能

在当今能源紧缺的情况下,超级电容器由于具有功率密度高、充放电时间短、循环寿命长等优点而被广泛应用于工业自动化控制、电力、国防以及新能源汽车等众多领域。本文以十八胺修饰的四氧化三铁纳米粒子(Fe_3O_4-ODA),氧化石墨烯(GO)以及苯胺单体为原料,通过原位聚合成功制备了Fe_3O_4-ODA/GO/PANI三元复合电极材料,其比电容高达516F/g,远高于二元复合材料GO/PANI和Fe_3O_4-ODA/PANI的比电容(分别为224F/g和345F/g)。并且,在1000次循环充放电之后,其容量仍可维持86.5%。此外,利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线粉末衍射(XRD)和傅立叶变换红外光谱仪(FT-IR)等手段对该复合材料的形貌和结构进行了表征。     

Synthesis and characterization of Dy(OH)3 and Dy2O3 nanotubes

Dy(OH)3 nanotubes with high aspect ratios of up to about 50 were synthesized in the presence of poly(ethylene glycol) via a hydrothermal method. Poly(ethylene glycol), as a nonionic surfactant, plays an important role in the formation of morphologies. Subsequent thermal treatment of Dy(OH)3 nanotube precursors at 450 degrees C for 6 h led to Dy2O3 nanotubes, during which the precursor tubular morphology was maintained. Selected-area electron diffraction and high-resolution transmission electron microscopy reveal the single-crystal nature of the Dy(OH)3 and Dy2O3 nanotubes. The morphologies and crystalline structure of the as-obtained products were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction, respectively. By this method, we can obtain a mass of products.     

White luminescence of Dy3+ ions doped 12CaO 7Al2O3 nanopowders under UV light excitation

12CaO 7Al2O3:Dy3+ nanopowders were successfully synthesized by the chemical co-precipitation method. X-ray diffraction result shows that the single 12CaO 7Al2O3 phase is formed with Dy3+ ions to replace the Ca2+ ions in the host of 12CaO 7Al2O3. The yellow and blue emissions, attributed to the forced electric dipole transition of 4F(9/2) --> 6H(13/2) centered at 571 nm and the magnetic dipole transition of 4F(9/2) --> 6H(15/2) centered at 480 nm, respectively, were observed. The integrated intensity ratios of yellow to blue increase from 1.63 to 1.70 with Dy3+ concentration increasing from 0.8 to 2.0% for the as-prepared 12CaO 7Al2O3:xDy3+ phosphor. The significantly enhanced emission intensities of 12CaO 7Al2O3:1.0% Dy3+ phosphor annealed at 900 degrees C for 2 hours in vacuum ambient could be ascribed to the decrease of OH(-) groups and the change of the surface topography. The thermal stability and the Commission International de l'Eclairage coordinates were also investigated. All the photoluminescence characteristics indicate that Dy3+ ions doped 12CaO 7Al2O3 may be a good candidate for the solid state lighting phosphor as well as white light-emitting diodes.     

BaAl_2O_4:Eu~(2+),Dy~(3+)长余辉发光材料的燃烧合成及其发光特性

以金属硝酸盐和尿素为原料,采用燃烧法合成了发青绿光的BaAl2O4:Eu2+,Dy3+长余辉发光材料。采用XRD、SEM、荧光分光光度计等手段对其进行分析表征。研究结果表明:随着燃烧温度升高,燃烧反应加剧,副产物BaCO3的含量减少,BaAl2O4的结晶程度增加,晶粒尺寸增大。Ba-Al2O4:Eu2+,Dy3+的激发光谱和发射光谱峰值分别为310nm和500nm,均呈宽谱带特征,其发光是由Eu2+的4f65d1→4f7跃迁引起,长余辉特性主要基于Dy3+的电子陷阱作用。     

Self-assembly of flower-like polyaniline–polyvinyl alcohol multidimensional architectures from 2D petals

Flower-like polyaniline–polyvinyl alcohol (PANI/PVA) multidimensional architectures assembled from 2D petals were successfully synthesized in the dilute solution of PVA by the oxidation polymerization. PANI/PVA flowers have a diameter of about 2.5 μm and consist of many interlaced sheet petals. Chemical structure and composition of polymerized PANI/PVA were characterized by Fourier transform infrared (FTIR) spectroscopy, Ultraviolet and visible spectroscopy (UV–vis), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In order to research the formation mechanism of the 3D flower-like PANI/PVA, their growth process was followed by measuring the morphological evolutions of products with the different polymerization times. The results showed that the flower-like PANI/PVA originated from sheet petals, which then self-assembled into flower-like microstructures. In addition, the effect of PVA concentration on the morphology of the 3D flower-like PANI/PVA was also investigated.     

Investigation of solar-induced photoelectrochemical water splitting and photocatalytic dye removal activities of camphor sulfonic acid doped polyaniline-WO_3-MWCNT ternary nanocomposite

The camphor sulfonic acid doped polyaniline-WO_3-multiwall carbon nanotube(CSA PANI-WO_3-CNT)ternary nanocomposite was synthesized during in-situ oxidative polymerization and characterized by Fourier transform infrared(FTIR) spectroscopy, Raman spectroscopy, X-ray diffraction(XRD), Field emission scanning electron microscopy(FESEM), X-ray photoelectron spectroscopy(XPS), Transmission electron microscopy(TEM), and Energy-dispersive X-ray spectroscopy(EDS). The application of CSA PANIWO_3-CNT ternary nanocomposite was investigated as the photocatalyst in the degradation of methylene blue dye(MB) and as the noble metal-free photoanode in photoelectrochemical water splitting under solar light irradiation. The degradation percentage of MB dye after 60 min illumination by CSA PANI-WO_3-CNT ternary nanocomposite reached 91.40% which was higher than that of pure WO_3(43.45%), pure CSA PANI(48.4%) and CSA PANI-WO_3 binary nanocomposite(85.15%). The photocurrent density of indium tin oxide(ITO)/CSA PANI-WO_3-CNT photoanode obtained 0.81 m A/cm~2 at 1.23 V vs. reversible hydrogen electrode under illumination which was 1.27, 2.13, and 4.26 times higher than that of the ITO/CSA PANI-WO_3(0.64 m A/cm~2), ITO/pure CSA PANI(0.38 m A/cm~2), and ITO/pure WO_3(0.19 m A/cm~2). Also,the applied bias photon-to-current efficiency(ABPE) of ITO/CSA PANI-WO_3-CNT was obtained 0.11%which showed two-fold, four-fold, and five-fold enhancements compared to the ITO/CSA PANI-WO_3,ITO/CSA PANI, and ITO/WO_3, respectively. The electrochemical impedance spectroscopy, as well as the Mott-Schottky results, confirmed the better photoelectrocatalytic activity of ITO/CSA PANI-WO_3-CNT in comparison with ITO/WO_3, ITO/CSA PANI, and ITO/CSA PANI-WO_3. The observed improvement in the photocatalytic and photoelectrocatalytic performances of WO_3 in the presence of CSA PANI is due to the formation of type-II heterojunction between WO_3 and CSA PANI which allows the separation of charge carriers easier and faster. On the other hand, MWCNT addition to the CSA PANI-WO_3 nanocomposite provided the conducting substrate for efficient interfacial charge separation as well as transferring.     

Fe(3)O(4)@Au/polyaniline multifunctional nanocomposites: their preparation and optical, electrical and magnetic properties

Fe(3)O(4)@Au/polyaniline (PANI) nanocomposites were fabricated by in situ polymerization in the presence of mercaptocarboxylic acid. The mercaptocarboxylic acid was used to introduce hydrogen bonding and/or electrostatic interaction; it acts as a template in the formation of Fe(3)O(4)@Au/PANI nanorods. The morphology and structure of the resulting nanocomposites were analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, x-ray diffraction and x-ray energy dispersion spectroscopy (EDS). It was found that the nanocomposites were rod-like with an average diameter of 153?nm, and they exhibited a core-shell structure. A UV-visible spectrometer, semiconductor parameter analyzer and vibrating sample magnetometer (VSM) were used to characterize the optical, electrical and magnetic properties of the Fe(3)O(4)@Au/PANI nanocomposites. It was interesting to find that these properties are dependent on the molar ratio of Au to Fe(3)O(4) when the molar ratio of Fe(3)O(4)@Au to PANI is fixed. The magnetic property of the Fe(3)O(4)@Au/PANI nanocomposite is very close to superparamagnetic behavior.     

Eu2+、Dy3+、Li+共掺杂CaSi2O2N2荧光粉的发光性能

采用高温固相反应法制备了一系列白光LED用CaSi2O2N2:0.05Eu2+,xDy3+,xLi+(0≤x≤0.03)荧光粉.利用X射线衍射仪对样品的物相结构进行了分析,结果表明:Dy3+和Li+离子的掺入没有改变CaSi2O2N2:Eu2+荧光粉的主晶相.利用荧光光谱仪对样品的发光性能进行了测试,发现所有样品的激发光谱均覆盖了从近紫外到蓝光的较宽范围,400 nm激发下得到的发射光谱为宽波段的单峰,峰值位于545 nm左右,是Eu2+离子5d-4f电子跃迁引起的.Dy3+离子掺杂可以提高CaSi2O2N2:Eu2+荧光粉的发光强度,Dy3+与Li+共掺杂可进一步提高荧光粉的发光强度,当Dy3+和Li+的掺杂量为1mol%时,荧光粉的发光强度达到最大值,是单掺杂Eu2+的荧光粉发光强度的157%.     

Preparation of polyaniline dispersions with different assembly structure

Polyaniline (PANI) dispersions with different assembly structure were prepared using sodium dodecyl benzene sulfonate (SDBS) as surfactant. Based on the images from the microscopy, it was found that the assembly structure of the PANI dispersions could be changed with different preparation conditions, including the concentration ratio of SDBS to HCl, SDBS to aniline and aniline to ammonium persulfate. UV-Vis spectra, conductivity and size distribution of the dispersions were also measured. The dispersions showed good stability and existed without precipitate at least half a year.