纳米氧化铟薄膜的制备及性质研究

发布时间：2018-02-11 22:15

本文关键词： 纳米氧化铟薄膜八面体结构气敏性光解水　出处：《济南大学》2015年硕士论文　论文类型：学位论文

【摘要】：氧化铟作为一种重要的n型半导体材料,具有2.8-3.6电子伏特的带隙,被广泛应用在气体传感器,光电器件,太阳能转换等领域。近年来,低维氧化铟纳米结构,如纳米线、纳米棒、纳米带等,多有报道,而作为一种有望在气敏、场发射等领域有重要应用的八面体结构的氧化铟,其报道的较少,且仅有的报道其合成方法主要为化学气相沉积法。本文着重研究如何通过温和的液相化学路线来制备八面体结构的氧化铟,并通过调控其微观结构,进一步研究材料结构和性质之间的关系。主要的研究内容如下:1.基于普通玻璃基片的氧化铟八面体薄膜的制备及其气敏性质研究通过溶胶凝胶法在普通的载玻片上制备纳米氧化铟薄膜。实验探讨了原材料氯化铟(InCl3·4H2O)、溶剂冰醋酸(C2H5COOH)以及添加剂乙二醇(HOC2H4OH)和柠檬酸(C6H8O7·H2O)用量对溶胶质量的影响,得到优化条件,即当In Cl3·4H2O为8.0 g,乙酸为10 mL,乙二醇为2 mL,乙醇为5 mL,水为3 mL,柠檬酸为1.2 g,低温回流时间为2.5 h时,所得溶胶其粘度适合制膜。之后分别采用提拉法和旋涂法制膜。对溶胶以90 mm·min-1的提拉速度得到凝胶膜,然后在500?C下退火4小时得到微观结构为纳米片的氧化铟薄膜;调节旋涂参数,使低转速为5000 rpm,时间为50 s,高转速为6500 rpm,时间为20 s进行旋涂,再在500?C下退火4 h得到微观结构为八面体的氧化铟薄膜。把两种氧化铟薄膜制成气敏传感器,在室温下分别测试了其对二氧化氮气体的响应。实验发现,相较于片状结构的氧化铟薄膜,八面体结构的氧化铟薄膜对二氧化氮气体有更高的灵敏度和分辨率,检测限达到了100 ppb;此外,气敏选择性实验表明,相较于其它常见的毒性气体,如CO、NH3和H2等,器件对二氧化氮具有良好的气敏选择性。2.基于FTO基片的掺氮氧化铟八面体结构薄膜的制备及其光解水性能研究薄膜采用上述的旋涂工艺进行制备。所用溶胶与上述溶胶基本相同,只是在其中添加了0.08 g的尿素。采用转速4500 rpm下旋涂50 s和随后高转速5000 rpm下旋涂20 s的工艺制得凝胶薄膜,然后经过500退火处理4小时,在FTO基片上得到氧化铟八面体纳米晶薄膜。作为对比,在FTO上用同样工艺制备了不掺氮的薄膜,即所用溶胶未添加尿素。以所制得的掺氮氧化铟八面体纳米晶薄膜为工作电极进行了光电化学分解水的实验。实验发现,在光强为一个太阳的模拟太阳光的照射下,掺氮改性后的八面体光解水的光电流可达到0.17 mA·cm-2,在实验的30 min内稳定,没有明显的衰减;而未掺氮的光电流只有0.03 mA·cm-2。
[Abstract]:As an important n-type semiconductor material, indium oxide has a band gap of 2.8-3.6 electron volts. It has been widely used in gas sensors, photovoltaic devices, solar energy conversion and other fields. In recent years, low-dimensional indium oxide nanostructures, such as nanowires, have been widely used. Nanorods, nanobelts, etc., are mostly reported. However, as a kind of indium oxide, which is expected to have important applications in gas sensing, field emission and other fields, there are few reports of indium oxide. The only reported method of synthesis is chemical vapor deposition. This paper focuses on the preparation of indium oxide with octahedron structure through a mild liquid chemical route, and regulates its microstructure. The main research contents are as follows: 1. Preparation and gas sensing properties of indium oxide octahedron thin films based on ordinary glass substrates. The effects of raw material indium chloride (InCl _ 3 路4H _ 2O), solvent glacial acetic acid (C _ 2H _ 5COOH), as well as additives ethylene glycol (HEC _ 2H _ 4OH) and citrate (C _ 6H _ 8O _ 7 路H _ 2O) on the sol quality were investigated. When in Cl3 路4H 2O was 8.0g, acetic acid was 10 mL, ethylene glycol was 2 mL, ethanol was 5 mL, water was 3 mL, citric acid was 1.2g, reflux time at low temperature was 2.5h. The viscosity of the obtained sol is suitable for film preparation. Then the film is prepared by Czochralski method and spin-coating method respectively. The gel film is obtained at the Czochralski rate of 90 mm 路min-1 for the sol, and then the gel film is obtained at 500 mm 路min-1. After annealing for 4 hours under C, indium oxide thin films with nano-structure were obtained by adjusting the spin-coating parameters to make low rotation speed 5000 rpm, time 50 s, high rotation speed 6500 rpm, time 20 s, and then spin coating at 500s? Indium oxide thin films with octahedron structure were obtained by annealing at C for 4 h. Two indium oxide thin films were made into gas sensors and their responses to nitrogen dioxide gas were measured at room temperature. Compared with indium oxide thin films with sheet structure, indium oxide thin films with octahedron structure have higher sensitivity and resolution to nitrogen dioxide gas, and the detection limit reaches 100 ppb. Compared with other common toxic gases, such as COG NH 3 and H 2, The device has good gas sensitivity selectivity to nitrogen dioxide. 2. Preparation and photolysis properties of indium oxide octahedron structure films based on FTO substrates; thin films prepared by the above spin-coating process. The sol is basically the same, Only 0.08 g urea was added to the gel film. The gel film was prepared by spinning 50 s under rotating speed of 4 500 rpm and 20 s at high speed of 5 000 rpm. The film was then annealed for 4 hours. Indium oxide octahedral nanocrystalline thin films were prepared on FTO substrates. Using the prepared indium oxide octahedron nanocrystalline film as the working electrode, the photochemical decomposition of water was carried out. It was found that the photochemical decomposition of water was carried out when the light intensity was simulated by the sun. The photocurrent of nitrogen-doped octahedron photodissociated water can reach 0.17 Ma 路cm ~ (-2), which is stable and has no obvious attenuation within 30 min of experiment, but the photocurrent without nitrogen doping is only 0.03 Ma 路cm ~ (-2).
【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ133.53;TB383.2

【参考文献】