铝掺杂氧化锌晶须/环氧树脂抗静电性能研究

采用新的铝掺杂方法,降低了氧化锌晶须的本体电阻率;研究了铝掺杂对氧化锌晶须电阻率的影响。含20%掺量的氧化铝使氧化锌晶须的表面电阻率从107~108Ω降低到1·6×106Ω,体积电阻率从108~109Ω·cm降低到7·1×105Ω·cm;研究了铝掺杂氧化锌晶须对环氧树脂抗静电性能的影响,铝掺杂氧化锌晶须的添加量为8%,使涂层的表面电阻降低到7·2×1010Ω。     

Cu掺杂SnO2纳米粉体的制备及气敏特性

控制不同n(Cu2+)/n(Sn4+),用均匀共沉淀法制备了平均粒径约80 nm的金红石型结构Cu掺杂SnO2纳米粉体;并以白云母为基片制备出Cu掺杂SnO2气敏元件。用TG-DSC、XRD、SEM对样品的相变、结构、形貌进行了分析,并测试了气敏元件的阻温特性和75℃氢气敏感性能。结果表明,Cu掺杂抑制了SnO2晶核的生长,使SnO2结晶度由约75%减小到50%,晶粒尺寸由约18 nm减小到6 nm;Cu掺杂使n型半导体SnO2的空气电阻值由1~8 kΩ提高到9×105~3×107MΩ,并使元件在75℃对体积分数为2 000×10-6氢气的灵敏度提高约20倍;n(Cu2+)/n(Sn4+)≈0.01时,元件对体积分数为4 000×10-6氢气的灵敏度高达约42。     

溅射时间对GZO薄膜光电性能的影响

采用射频磁控溅射法在普通玻璃衬底上制备了Ga2O3含量为3wt.％的掺镓氧化锌透明导电薄膜(GZO).通过X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)、四探针测试仪、台阶仪、UV-Vis-NIR3600型紫外-可见分光光度计研究了溅射时间对薄膜结构、表面形貌及光电性能的影响.结果表明,溅射时间为40 min时制备的GZO薄膜的光电综合性能最好,可见光区透过率峰值86％,方阻为16.4Ω/□,电阻率为1.18 ×10-3Ω·cm,性能指数ΦTc为4.73 ×10-3 Ω-1;随着溅射时间增加,薄膜光学带系从3.69 eV减少到3.56 eV.在溅射时间60 min时结晶度最高,方块电阻为9.0Ω/□,电阻率最低为9.7×10-4 Ω·cm,可见光透过率峰值为81％.     

种子层及掺杂浓度对溶胶-凝胶法制备ZnO∶Al薄膜光电性能的影响

本文采用溶胶-凝胶法以提拉的方式在普通玻璃基底上制备出n型掺杂具有优良光电性能的氧化锌掺铝(AZO)薄膜,并以磁控溅射AZO薄膜为种子层引导液相法所制备AZO薄膜生长.Al掺杂浓度区间为0.25at％～5.00at％.通过X射线衍射仪、场发射扫描电子显微镜、轮廓仪、方块电阻测试仪、霍尔效应测试仪、紫外-可见-红外分光光度计分别研究了薄膜物相、微观结构、膜厚及光电性能,进一步分析了Al掺杂浓度、种子层对薄膜光电性能的影响.结果表明:经10次提拉所制备薄膜可见光透过率85％以上.Al掺杂浓度、种子层的引入对AZO薄膜的光电性能有重要影响.无种子层时,掺杂浓度为0.50at％的AZO薄膜在5％ H2、95％N2还原气氛下于550℃保温60 min得到最优电学性能,方块电阻约为166 Ω/□,电阻率约为1.99×10-3 Ω·cm;预镀AZO种子层所制备薄膜方块电阻下降到约42Ω/□,电阻率下降到约7.56×10-4Ω·cm.     

硼掺杂量对P型a-Si:H膜微结构和光/电学性能的影响

采用等离子体增强化学气相沉积法制备了不同硼掺杂比的P型a-Si:H系列薄膜。研究了硼掺杂比对P型a-Si:H薄膜微结构和光/电学性能的影响;同时,对最优掺杂比下的P型a-Si:H薄膜进行了真空退火处理,以研究薄膜晶体结构的改变对其光/电学性能的影响。结果表明:随着硼掺杂比的增加,P型a-Si:H薄膜的非晶结构没有实质改变,但其光学带隙及电学性能均有明显变化,总结出最佳硼掺杂比为1.0%。经真空退火处理后,P型a-Si:H薄膜的有序程度明显提高,光学带隙从1.81eV降低到1.72eV,电导率提高3个数量级。薄膜的晶体结构比硼掺杂量对薄膜电学性能的改善更为显著。     

抗静电涤纶屏蔽性能的研究

在自制抗静电涤纶的基础上,均匀掺杂一些新的导电粒子,如碳纳米管(CNTs)、银粉和铁粉,研究其抗静电及屏蔽性能的变化。结果表明:自制抗静电涤纶的比电阻为5.6×10~9Ω·cm,在电磁波频率为30～100 MHz时,屏蔽效率小于10 dB。掺入铁粉和银粉后,其比电阻增大,屏蔽效果提高。当抗静电母粒和含CNTs质量分数为6%的PA6母粒质量比为7:3时,所得纤维的比电阻为2.1×10~9Ω·cm,在电磁波频率为30～100 MHz时屏蔽效率为20 dB以上,进一步涂敷自制导电涂料后,比电阻为1.9×10~9Ω·cm,屏蔽效率为25～30 dB,屏蔽性能良好。     

导电纳米颗粒对Sb:SnO2薄膜性能影响研究

采用水热晶化法,通过控制水热反应条件、溶液的浓度以及矿化剂的种类等因素,制备出分散性及导电性良好的SnO2纳米颗粒.采用溶胶-凝胶浸渍镀膜的方法制备Sb掺杂SnO2薄膜,在镀膜溶液的配制过程中引入SnO2纳米颗粒悬浮液,经陈化后最终得到镀膜溶液.采用van der Pauw法、UV/VIS分光光度计以及Fourier变换红外光谱仪研究和分析了添加纳米颗粒对膜层导电性能、光学性能以及膜层结构的影响;采用场发射扫描电镜研究了膜层的表面形貌.结果表明导电纳米颗粒的加入可有效提高膜层的导电性能,当SnO2纳米颗粒添加质量分数为10%时,膜层的电阻率为6.5×10…3Ω·cm;添加和未添加纳米颗粒的膜层的可见光透过率均为85%.纳米颗粒参与了溶胶-凝胶制备薄膜网络的形成,提高了膜层结构的连续性,从而使膜层具有较好的导电性能和光学性能.     

镍掺杂对FTO薄膜光电性能的影响及机理分析

本文以单丁基三氯化锡(MBTC)为锡源,氟化铵(NH₄F)为氟源,甲醇为溶剂,六水合氯化镍(NiCl₂·6H₂O)为镍源,采用气溶胶辅助化学气相沉积(AACVD)制备了镍掺杂FTO薄膜。利用分光光度计、四探针电阻仪及霍尔效应测试仪对镍掺杂FTO薄膜的光学性能、电学性能进行表征和分析,并基于第一性原理对掺杂体系的电子结构进行了计算。结果表明,Ni掺杂的FTO薄膜为四方金红石结构,导电性能有所提高。当Ni/Sn为2%(原子数分数)时,品质因数Φ_TC达到3×10^-2Ω^-1,电阻率ρ为3.79×10^-4Ω·cm,可见光平均透过率约为80%,载流子浓度n为6.88×10²⁰ cm^-3,迁移率μ为13.31 cm²·V^-1·s^-1。     

掺杂工艺对Al-F共掺ZnO薄膜性能的影响

采用溶胶-凝胶旋涂工艺在普通玻璃基片上制备出Al-F共掺杂ZnO薄膜,共掺杂离子浓度从0．25％增加到1．25％,退火气氛分别为空气、氢气和氩气,退火温度均为450℃。利用SEM测试方法研究了共掺杂离子浓度和退火气氛对薄膜表面形貌的影响;用紫外-可见分光光度计及四探针法等仪器对其对其透光性以及电阻率进行了测试,进一步研究了退火气氛对薄膜光电性能的影响。结果表明：制备的Al-F共掺杂ZnO薄膜多数表面平整,晶粒致密均匀;各种气氛下制备的薄膜在可见光大部分范围内透过率均超过80％;通过比较不同气氛下各种薄膜的电阻率,得知在H2气氛中退火处理后其电阻率最低为9．36×10^-2Ω·cm;与单一掺杂Al离子或F离子的薄膜相比较,Al—F共掺ZnO薄膜电阻率最低。     

聚丙烯抗静电纤维的研究Ⅰ.不同共混体系抗静电性能

分别对 3种不同的抗静电体系 PP/PET-PEG,PP/PEG/Cu I和 PP/PET-PEG/PEG/Cu I的抗静电性能进行了研究。结果表明 :三类共混体系均有一定的抗静电性能 ,其中以 PP/PET-PEG/PEG/Cu I共混体系的抗静电性能最好。当抗静电剂添加为总量的 6%时 ,其体积电阻率可达 6.8× 10 9Ω· cm,抗静电性能对环境相对湿度的敏感性低于 PP/PET-PEG体系 ,且纤维的力学性能较 PP/PEG/Cu I体系有所改进。共混体系为海相 -微纤复合结构。     

Influence of a Ni interlayer on the optical and electrical properties of trilayer GZO/Ni/GZO films

Trilayer GZO/Ni/GZO films were deposited onto polycarbonate (PC) substrates with RF and DC magnetron sputtering, and then the influence of a Ni interlayer on the optical and electrical properties of the films was investigated. A 2-nm-thick Ni interlayer decreased the resistivity to 6.4×10⁻⁴ Ω cm and influenced the optical transmittance.Although optical transmittance deteriorated with Ni insertion, the films showed a relatively high optical transmittance of 74.5% in the visible wavelength region. The figure of merit (FOM) of a GZO single layer film was 1.2×10⁻⁴ Ω⁻¹, while that of the GZO/Ni/GZO films reached a maximum of 8.2×10⁻⁴ Ω⁻¹.Since a higher FOM results in higher quality transparent-conductive oxide (TCO) films, it is concluded that GZO films with a 2 nm Ni interlayer have better optoelectrical performance than single-layer GZO films.     

Structural,optical, electrical and dielectric properties of Bi1·5Zn0·92Nb1·5−xNixO6·92−3x/2 solid solution

Abstract

The effects of Ni content on the structural, optical, dielectric and electrical properties of Bi_1·5Zn_0·92Nb_1·5O_6·92 pyrochlore ceramics have been investigated. Nickel atoms were inserted into pure samples in accordance to the composition Bi_1·5Zn_0·92Nb_1·5?xNi_xO_6·92?3x/2, with x varying from 0·07 to 0·40. The structural analysis revealed that a single phase of the pyrochlore compound can be obtained for x values of 0·07 and 0·10 only. Further increase in Ni caused the appearance of multiple phases. The optical energy band gaps are determined as 3·30, 3·35 and 3·52 eV for Ni content of 0·00, 0·07 and 0·10 respectively. The temperature dependent electrical resistivity and the frequency dependent capacitance are observed to increase with increasing Ni content. The resonance frequency, which was determined from the capacitance–frequency dependence, was observed to shift from 12·14 to 10·47 kHz as the x values increase from 0·00 to 0·10 respectively.     

Concentration dependence of physical properties of low temperature processed ZnO quantum dots thin films on polyethylene terephthalate as potential electron transport material for perovskite solar cell

Colloidal Zinc oxide quantum dots (ZnO QDs) prepared with varying concentrations through precipitation method were deposited on flexible ITO/PET substrates using spin-coating technique. Various characterization tools were utilized to investigate the morphological, structural, electrical and optical properties of the films. The crystallinity of the films was found to improve with increasing ZnO QD concentration (ZQ_C) as evident from the X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) studies. Crystallographic and optical parameters were evaluated and explained in depth. The average nanograin size and bandgap were increased and decreased respectively, from ～5 nm to ～8 nm and 3.29 eV–3.24 eV with an increase in ZQ_C from 10 mg/mL to 70 mg/mL. Columnar structure growth of the films is revealed by AFM results. The films showed decent optical transparency up to 81%. All the ZnO films exhibited n-type semiconducting property as indicated by the electrical measurements with carrier mobility and low resistivity of 12.21–26.63 cm²/Vs and 11.84 × 10^?3 to 13.16 × 10^?3 Ω cm respectively. Based on the experimental findings, ZnO QD nanostructure film grown at 50 mg/mL is envisaged to be a potential candidate for flexible perovskite photovoltaic application.     

Effects of polymerization medium on electrical conductivity and optical properties of organic semiconductor-based polypyrrole

The effects of tetrabutylammonium tetrafluoroborate (TBAFB), tetrabutylammonium hexafluorophosphate (TBAPF₆), and paratoluene sulfonoicacid (PTSA) polymerization mediums on the electrical conductivity and optical properties of the polypyrrole (PPy) have been investigated. The electrical conductivity and optical properties of the samples polymerized in presence of TBAFB, TBAPF₆, and PTSA organic salts change with medium of prepared polymer. The electrical conductivity of the TBAFB, PTSA, and TBAPF₆ samples at 27°C were found to be 3.43 × 10⁻¹, 4.48 × 10⁻², and 1.60 × 10⁻⁴ (S/cm), respectively. The lowest optical band gap of the polymer was found to be 2.23 eV. The refractive index dispersion of the samples obeys single oscillator model. The obtained results suggest that polymerization medium changes electrical conductivity and optical properties of the PPy. POLYM. ENG. SCI., 47:1016–1020, 2007. © 2007 Society of Plastics Engineers     

Effect of Au ion beam on structural,surface, optical and electrical properties of ZnO thin films prepared by RF sputtering

In the present work, ZnO thin films were irradiated with 700?keV Au⁺ ions at different fluence (1?× 10¹³, 1?× 10¹⁴, 2?× 10¹⁴ and 5?× 10¹⁴ ions/cm²). The structural, morphological, optical and electrical properties of pristine and irradiated ZnO thin films were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), scanning electron microscope (SEM), spectroscopy ellipsometry (SE) and four point probe technique respectively. XRD results showed that the crystallite size decreased from pristine value at the fluence 1?×?10¹³ ions/cm², with further increase of ion fluence the crystallite size also increased due to which the crystallinity of thin films improved. SEM micrographs showed acicular structures appeared on the ZnO thin film surface at high fluence of 5?×?10¹⁴ ions/cm². FTIR showed absorption band splitting due to the growth of ZnO nanostructures. The optical study revealed that the optical band gap of ZnO thin films changed from 3.08?eV (pristine) to 2.94?eV at the high fluence (5?× 10¹⁴ ions/cm²). The electrical resistivity of ZnO thin film decreases with increasing ion fluence. All the results can be attributed to localized heating effect by ions irradiation of thin films and well correlated with each other.     

The optical and electrical properties of ZnO:Al thin films deposited at low temperatures by RF magnetron sputtering

Several ZnO:Al thin films have been successfully deposited on glass substrates at different substrate temperatures by RF (radio frequency) magnetron sputtering method. Effects of the substrate temperatures on the optical and electrical properties of these ZnO:Al thin films were investigated. The UV–VIS–NIR spectra of the ZnO:Al thin films revealed that the average optical transmittances in the visible range are very high, up to 88%. X-ray diffraction results showed that crystallization of these films was improved at higher substrate temperature. The band gaps of ZnO:Al thin films deposited at 25 ℃, 150 ℃, 200 ℃, and 250 ℃ are 3.59 eV, 3.55 eV, 3.53 eV, and 3.48 eV, respectively. The Hall-effect measurement demonstrated that the electrical resistivity of the films decreased with the increase of the substrate temperature and the electrical resistivity reached 1.990×10^?3 Ω cm at 250 ℃.     

Distribution of relaxation time in solution-processed polycrystalline CZTS thin films: Study of impedance spectroscopy

Here we report the complex impedance spectroscopic analysis of polycrystalline CZTS thin films synthesized by sol-gel spin coating technique without any post deposition sulphurization. The films are characterized by microstructural, compositional, optical and electrical studies to confirm the formation of kesterite phase of CZTS comprises of well distributed compact grains with the optical band gap 1.44?eV. Room temperature electrical characterizations of the CZTS thin films by four-probe and Hall effect technique revealed the p-type conductivity of the films with resistivity ~ 1.45?×?10^?2 Ω?cm, mobility ~ 3.7?×?10³ cm² V^?1 s^?1 and carrier concentration ~ 1.82?×?10¹⁷ cm^?3. The distribution of relaxation time (DRT) function with improved frequency resolution is reconstructed from the impedance spectra of CZTS film recorded in the frequency range 50?Hz to 5?MHz at room temperature to identify the number of electrical processes in the polycrystalline film. The Nyquist plot is fitted into electrical model consist of three parallel combinations of resistor (R) and capacitor (C) in series as three major peaks in DRT function indicates the presence of different relaxation processes with major contributions from core grains along with smaller contributions from grain boundary and interfaces. The room temperature frequency dependence of dielectric constant, loss tangent and ac conductivity is also studied for the CZTS films.     

Sulphur doped DLC films deposited by DC magnetron sputtering

Diamond‐like carbon (DLC) and sulphur doped diamond‐like carbon (S‐DLC) films were synthesised at different sulphur molar percentage of 0%, 2%, 5%, 8% and 10% by direct current (DC) magnetron sputtering process using novel compressed sulphur‐graphite targets at relatively low power density. Films were characterised for their morphologies, structural, electrical and optical properties. Scanning electron microscope images reveal changes in the quality of the obtained films shown by the denser packing of DLC grains at different sulphur percentage. The conductivities of S‐DLC films were found to be in the range of 6.0 × 10^?3–0.6/Ω cm. The optical band gap energies were found to be in the range of ～1.4–2.0 eV. Both electrical and optical measurements exhibit nonlinear responses with optimum at around 5% sulphur molar percentage (minimum for conductivity and maximum for optical band gap energy). These trends of change in both conductivity and optical band gap energy are consistent with the variation in bond characters of the films indicated by Raman spectroscopy. © 2011 Canadian Society for Chemical Engineering     

Electrical and optical properties of diamond-like carbon films deposited by pulsed laser ablation

Pulsed laser ablation of a graphite target was carried out by ArF excimer laser deposition at a laser wavelength of 193 nm and fluences of 10 and 20 J/cm² to produce diamond-like carbon (DLC) films. DLC films were deposited on silicon and quartz substrates under 1 × 10^? 6 Torr pressure at different temperatures from room temperature to 250 °C. The effect of temperature on the electrical and optical properties of the DLC films was studied. Laser Raman Spectroscopy (LRS) showed that the DLC band showed a slight increase to higher frequency with increasing film deposition temperature. Spectroscopic ellipsometry (SE) and ultraviolet–visible absorption spectroscopy showed that the optical band gap of the DLC films was 0.8–2 eV and decreased with increasing substrate temperature. These results were consistent with the electrical resistivity results, which gave values for the films in the range 1.0 × 10⁴–2.8 × 10⁵ Ω cm and which also decreased with deposition temperature. We conclude that at higher substrate deposition temperatures, DLC films show increasing graphitic characteristics yielding lower electrical resistivity and a smaller optical band gap.     

Influence of sintering atmosphere and BN additives on microstructure and properties of porous SiC ceramics

The effects of the boron nitride (BN) content on the electrical, thermal, and mechanical properties of porous SiC ceramics were investigated in N₂ and Ar atmospheres. The electrical resistivity was predominantly controlled by the sintering atmosphere and secondarily by the BN concentration, whereas the thermal conductivity and flexural strength were more susceptible to changes in the porosity and necking area between the SiC grains. The electrical resistivities of argon-sintered porous SiC ceramics (6.3 × 10⁵ – 1.6 × 10⁶ Ω·cm) were seven orders of magnitude higher than those of nitrogen-sintered porous SiC ceramics (1.5 × 10⁻¹ – 6.0 × 10⁻¹ Ω·cm). The thermal conductivity and flexural strength of the argon-sintered porous SiC ceramics increased from 8.4–11.6 W·m⁻¹ K⁻¹ and from 9.3–28.2 MPa, respectively, with an increase in the BN content from 0 to 1.5 vol%, which was attributed to the increase in necking area and the decrease in porosity.