电化学制备MgZnO纳米材料及其性能研究

发布时间：2018-01-22 16:04

  本文关键词： 掺杂 MgZnO纳米材料 ZnO纳米柱 电化学沉积　出处：《哈尔滨工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：由于Zn O半导体材料在室温下具有较高的激子结合能,良好的压电性能以及光电性能,Zn O半导体材料在环境监测、导弹尾焰、太阳能电池和液晶显示器等领域有着广泛的应用前景,逐渐成为研究者研发的热点。由于本征Zn O半导体材料的带隙为3.37e V,因此,基于Zn O材料制备的紫外探测器只能探测到某一特定的波长,无法用于整个紫外波段的探测。为了拓宽Zn O基紫外探测器的探测波段,本课题采用Mg掺杂的方法,力求对Zn O半导体材料的禁带宽度进行可控的调整。世界各国的研究者已经通过MOCVD、MBE、PLD、磁控溅射等实验方法成功研制出满足日盲紫外波段的Mg Zn O纳米材料,但是,关于电化学法制备高Mg组分的Mg Zn O纳米材料的研究还没有相关报道。本实验采用电化学法制备Mg Zn O纳米材料,具体的研究内容如下:1.以提拉法在ITO导电衬底上制备出Zn O种子层,采用电化学法制备Zn O纳米柱阵列。研究表明,改变提拉次数,可以提高Zn O纳米柱的结晶度和取向性,使Zn O纳米柱垂直于衬底表面。2.通过加入不同浓度的硝酸锌和硝酸镁电解液,研究Mg2+对于Zn O形貌的影响。当电解液中Zn2+浓度较低时,加入适量的Mg2+,可以制备出柱状结构的Zn O;当电解液中Zn2+浓度较高时,加入适量的Mg2+,可以制备出片状结构的Zn O。3.采用电化学法,通过调节不同浓度比的硝酸锌和硝酸镁电解液,实现Mg掺杂Zn O,制备出Mg Zn O纳米材料。由XRD表明,随着掺杂含量的升高,Mg Zn O纳米材料的(002)衍射峰有轻微的移动。当硝酸锌浓度一定时,Mg Zn O纳米材料的尺寸,随着硝酸镁浓度的升高,先增大后减小,这是由于溶液中的Mg2+、Zn2+、OH-离子的浓度不平衡所致。当硝酸锌电解液为2m M,硝酸镁为4m M时,制备的Mg Zn O纳米材料取向性良好,结晶度高,尺寸较小,是制备Mg Zn O纳米材料的最佳电解液浓度。在此电解液氛围下,研究了沉积电压和沉积温度对于Mg Zn O的影响。结果表明,最佳的沉积电位为-1V,最优沉积温度为60℃。
[Abstract]:Due to the high exciton binding energy, good piezoelectric and photoelectric properties of Zno semiconductor material at room temperature, the Zno semiconductor material is monitored in the environment, and the missile tail flame. Solar cells and liquid crystal display (LCD) have been widely used in many fields, and have gradually become the focus of research and development. Because the band gap of intrinsic ZnO semiconductor material is 3.37e V, therefore. The UV detector based on Zno material can only detect a specific wavelength and can not be used to detect the whole ultraviolet band. In order to broaden the detection band of Zn-O based UV detector. In this paper, the Mg-doped method is used to adjust the bandgap of Zn-O semiconductor materials in a controllable way. Researchers in the world have adopted MOCVD / MBEPLD to control the bandgap of Zn-O semiconductor materials. Magnetron sputtering and other experimental methods have been successfully developed to meet the solar blind ultraviolet band mg Zn O nanomaterials, but. The preparation of mg Zn O nanomaterials with high mg composition by electrochemical method has not been reported. In this experiment, mg Zn O nanomaterials were prepared by electrochemical method. The specific research contents are as follows: 1. Zno seed layer was prepared on ITO conductive substrate by Czochralski method, and Zn-O nano-column array was prepared by electrochemical method. The crystallinity and orientation of Zn-O nano-column can be improved by adding different concentration of zinc nitrate and magnesium nitrate electrolyte. The Zn-O nano-column is perpendicular to the substrate surface. The effect of Mg2 on Zn-O morphology was studied. When the concentration of Zn2 in electrolyte was low, the columnar ZnO could be prepared by adding proper amount of Mg2. When the concentration of Zn2 in electrolyte is high, Zn 0.3 with flake structure can be prepared by adding proper amount of Mg2. Zinc nitrate and magnesium nitrate electrolyte with different concentration ratio can be prepared by electrochemical method. Mg Zn O nanomaterials were prepared by doping Zn O with mg. XRD showed that with the increase of doping content, mg Zn O nanomaterials were obtained. When the concentration of zinc nitrate is fixed, the size of mg Zn O nanomaterials increases firstly and then decreases with the increase of magnesium nitrate concentration. This is due to the imbalance of the concentration of Mg2 ~ (2 +) Zn _ (2) O _ (-) ion in the solution, when zinc nitrate electrolyte is 2m M and magnesium nitrate is 4 mm. The prepared mg Zn O nanomaterials have good orientation, high crystallinity and small size, which is the best electrolyte concentration for the preparation of mg Zn O nanomaterials. The effects of deposition voltage and deposition temperature on mg Zn O are studied. The results show that the optimum deposition potential is -1 V and the optimum deposition temperature is 60 鈩，

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