银纳米线的可控合成及其透明电极的性能表征

发布时间：2018-05-27 16:11

本文选题：银纳米线 + 透明电极　；参考：《国防科学技术大学》2015年硕士论文

【摘要】：银纳米线可用于制备光电性能优异且具柔性的透明电极,是最有希望替代ITO导电玻璃的新一代透明导电材料。理论研究表明,制备性能优异透明电极的银纳米线应具有细且长的特性,直径应小于30nm,长径比应不小于800。本文以合成细长银纳米线和制备高性能透明电极为目标,研究不同尺寸银纳米线的可控合成以及透明电极的制备、性能优化和表征。研究发现,用一锅多醇法工艺制备银纳米线易于实现其直径及长径比的可控。形核条件、生长阻力、生长速率、二次形核等是影响细长银纳米线合成的因素。论文系统研究了一锅多醇法制备细长银纳米线的反应体系及工艺参数,实现了直径40~100nm平均长度0.04~40μm范围内银纳米线的尺寸可控。重点研究各类卤化物成核控制剂对银纳米线合成反应中形核和生长过程的影响。建立了成核控制剂——成核大小——产物尺寸的物理模型。实验表明,选用NaCl/KBr体系混合形核剂,可合成出平均直径26nm,平均长度21μm,长径比超过800,满足高性能透明电极要求的细长银纳米线。分析认为,氯离子对反应活度的降低和溴离子对成核尺寸的控制是制备细长银纳米线的关键。在掌握银纳米线分离分散工艺的基础上,制备了银纳米线分散液(不含树脂粘接剂)及银纳米线墨水(含低体积分数树脂粘接剂),并用旋涂法分别在玻璃和PET两种基材表面制备出透明导电膜层。在玻璃和PET表面用优化的分散液配方制得的导电膜层在90%透过率下的方阻分别为17.6Ω/sq和29.5Ω/sq。而由墨水制备的膜层光电性能与分散液制备的膜层相当,经胶带粘揭后导电性能基本不变。旋涂法制得的银纳米线导电膜层经洗涤、加热、加压、介质还原等后处理可进一步提高透明电极的光电性能。各种处理的基本原理均为在不降低透光性能的基础上降低银纳米线网络节点的接触电阻,以提高膜层的导电性能。结果表明,在玻璃和PET基底上制备的细长银纳米线透明电极经加热处理后,在90%的透过率下方阻可低至10Ω/sq左右,显著优于ITO透明电极的光电性能。PET基底的银纳米线透明电极在加热后导电膜层的附着力明显提升。玻璃基底银纳米线透明电极经树脂覆盖后基底附着力大幅提高,经多次胶带粘揭方阻增大率小于10%。
[Abstract]:Silver nanowires can be used to prepare transparent electrodes with excellent optoelectronic properties and flexible properties. Silver nanowires are the most promising new generation transparent conductive materials to replace ITO conductive glass. The theoretical study shows that the silver nanowires with excellent properties should be fine and long, the diameter should be less than 30 nm and the aspect ratio should be not less than 800. In this paper, the controllable synthesis of silver nanowires with different sizes and the preparation, performance optimization and characterization of transparent electrodes were studied, aiming at the synthesis of thin silver nanowires and the preparation of high performance transparent electrodes. It is found that the diameter and aspect ratio of silver nanowires prepared by one pot polyol process are easy to be controlled. Nucleation conditions, growth resistance, growth rate and quadratic nucleation are the factors affecting the synthesis of thin silver nanowires. The reaction system and process parameters of thin silver nanowires prepared by one-pot polyol method were systematically studied in this paper. The size of silver nanowires was controlled in the range of 0.04 ~ 40 渭 m in the average diameter of 40~100nm. The effect of various halide nucleating agents on nucleation and growth of silver nanowires was studied. A physical model of nucleation control agent-nucleation size-product size was established. The experimental results show that the thin silver nanowires with an average diameter of 26 nm, an average length of 21 渭 m and a aspect ratio of more than 800 can be synthesized by using the mixed nucleating agent of NaCl/KBr system. It is considered that the reduction of the activity of chloride ion pair reaction and the control of the nucleation size of bromine ions are the key to the preparation of thin silver nanowires. On the basis of mastering the separation and dispersion process of silver nanowires, Silver nanowire dispersions (without resin adhesives) and silver nanowire inks (containing low volume fraction resin adhesives) were prepared. Transparent conductive films were prepared on glass and PET substrates by spin coating. At 90% transmittance, the square resistance of the conductive films prepared on glass and PET surfaces with optimized dispersion formula is 17.6 惟 / sq and 29.5 惟 / sqsqrespectively. The photovoltaic property of the film prepared by ink is similar to that of the film prepared by dispersions, and the conductivity of the film is basically unchanged after the adhesive of adhesive tape. After washing, heating, pressurizing and medium reduction, the silver nanowire film prepared by spin-coating method can further improve the photoelectric performance of transparent electrode. The basic principle of all kinds of processing is to reduce the contact resistance of the silver nanowire network nodes without reducing the transmittance of the silver nanowires in order to improve the conductivity of the film. The results show that the thin silver nanowire transparent electrode prepared on glass and PET substrate is heated, and the resistance can be as low as 10 惟 / sq at 90% transmittance. The photovoltaic properties of the silver nanowire transparent electrode which is obviously superior to that of the ITO transparent electrode. The adhesion of the conductive film layer of the silver nanowire transparent electrode after heating is obviously improved. The adhesion of glass substrate silver nanowire transparent electrode covered by resin was greatly improved, and the increase rate of square resistance was less than 100.The increase rate of glass substrate silver nanowire transparent electrode was less than 10%.
【学位授予单位】：国防科学技术大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB383.1;TQ131.22

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