金属氧化物基电致变色薄膜的制备及性能改善

发布时间：2018-05-31 13:31

本文选题：电致变色 + 氧化镍　；参考：《浙江大学》2014年博士论文

【摘要】：电致变色材料是指某些物质在一定的电压作用下,颜色会发生可逆的、持久的变化。电致变色材料由于其特定的功能和迷人应用前景而成为各国研究的热点。这种材料不仅可以应用在智能节能窗上,还可以用在低能耗显示器、汽车防炫目后视镜以及卫星、武器装备的红外隐身等各种领域。目前为止,日本,欧洲和美国一些工业强国在电致变色技术应用研究方面处于领先地位,尤其是在全固态电致变色器件研发上。由于我国在电致变色材料和器件方面的研究起步比较晚,与国外的先进应用研究技术还有一定的差距。另外,材料颜色变化单一、变色速度慢和循环寿命短等仍然制约着电致变色技术的发展。本论文以NiO、WO3和TiO2金属氧化物电致变色材料为主要研究对象,采用纳米化、复合化和掺杂等手段对其进行改性研究,主要目的是改善目前金属氧化物电致变色材料普遍存在的一些问题,如变色速度慢、光学调制范围小、变色效率低、循环寿命短和变色种类单一等。通过氯化胆碱基离子液体在ITO玻璃上电沉积金属Ni层,然后在空气中热处理氧化经过两步法制备成NiO薄膜,这种薄膜具有超快的电致变色速度、较高的变色效率和较好的循环稳定性,但是其光学调制范围比较小,而且制备工艺比较繁琐。为了解决上述两步法制备NiO薄膜的缺陷,通过在氯化胆碱基离子液体中加入氧化剂的方法直接制备出了NiO薄膜。这种NiO薄膜具有比较大的光学调制范围,在550nm处达到了67%,而且制备工艺简单,具有较好的记忆性能和良好的循环稳定性。结合水热和化学浴沉积法制备了TiO2/NiO核壳纳米棒阵列薄膜。与单纯的NiO纳米片薄膜相比,核壳结构的纳米棒阵列有利于电子的传输和离子的扩散,具有较大的光学调制范围、高的变色效率和良好的循环稳定性。通过电泳沉积和化学浴沉积法制备了NiO/石墨烯复合薄膜,由于石墨烯良好的电子导电性以及复合薄膜具有更大的空隙便于电解液的渗透和电子的传输,具有比较好的电化学活性和反应可逆性。相比于NiO纳米片薄膜,NiO/石墨烯复合薄膜具有更高的变色效率、快的电致变色速度和良好的循环稳定性,说明材料复合化是提高电致变色性能的有效途径。采用水热和溶剂热法制备了W03纳米片、纳米团簇、纳米树和纳米线薄膜。用水热法在FTO导电基底上生长的多孔结构W03纳米片,可以为电化学反应提供更大活性面积和便于离子扩散,具有很好的电化学性能和电致变色性能。相比于不同pH下制备的W03纳米束和纳米块,W03纳米片薄膜具有较高的变色效率,较快的电致变色速度,更大的光学调制范围和更好的循环稳定性。利用溶剂热法在FTO基底上生长了W03纳米树和纳米线薄膜,在可见光和红外区域都具有很突出的电致变色性能。特别地,在-0.7～1.0V区间W03纳米树和纳米线的光学调制在633nm处分别为66.5%和66%,在2000nm处分别为73.8%和53.9%,在8μm处分别为57.7%和51.7%,着色和褪色时间分别为4.6/3.6s和2.0/3.4s,变色效率分别为126和120cm2C-1,经过4500循环次后的光学调制范围分别是开始光学调制范围的77.5%和81.7%。通过水热反应制备不同浓度Ti掺杂的W03薄膜。在W03薄膜中掺杂低浓度Ti不仅降低了W03薄膜的结晶度,还改善了W03薄膜的微观形貌,形成了大孔的星状结构,为离子扩散和迁移提供了更多的路径,具有更大的光学调制范围、更快的电致变色速度和更高的变色效率。通过水热和电沉积法在FTO玻璃基底上制备了TiO2/WO3核壳纳米棒阵列,以单晶Ti02纳米棒为芯核、非晶态W03为壳层的异质结结构显著提高了材料的电致变色性能和电化学稳定性。与WO3薄膜相比,TiO2/WO3核壳纳米棒阵列具有较大的光学调制、较快的电致变色速度、高的变色效率和优异的循环稳定性。通过结合水热、溶剂热和电聚合方法分别制备了TiO2/PANI和WO3/PANI核壳纳米结构薄膜。金属氧化物/PANI核壳纳米阵列结构具有多变色效应,材料在紫色、绿色、黄色和蓝色之间相互转变。金属氧化物(?)PANI核壳纳米阵列还具有比较大的光学调制范围、高的变色效率和优异的循环稳定性。
[Abstract]:Electrochromic materials refer to the reversible and persistent changes in color of certain substances under the action of a certain voltage. Electrochromic materials have become a hot spot of research in various countries because of their specific functions and attractive application prospects. This material can be used not only on intelligent energy saving windows but also in low energy display and car protection. Eye mirrors and satellites, infrared stealth of weaponry and other fields. So far, some industrial powers in Japan, Europe and the United States are in the leading position in the application of electrochromic technology, especially in the research and development of all solid state electrochromic devices. Because of our country's research on electrochromic materials and devices In addition, there is still a certain gap between the advanced applied research technology abroad. In addition, the change of material color is single, the speed of discoloration is slow and the cycle life is short, etc. the electrochromic technology is still restricted. In this paper, NiO, WO3 and TiO2 metal oxide electrochromic materials are used as the main research objects, and the methods of nano, compound and doping are used. The main purpose of this study is to improve the current problems of metal oxide electrochromic materials, such as slow discoloration speed, small optical modulation range, low discoloration efficiency, short cycle life and single discoloration.
The metal Ni layer was electrodeposited on ITO glass by the ionic liquid of chloride bile base on ITO glass. Then, the NiO film was prepared by heat treatment and oxidation in the air. This film has super fast electrochromic speed, high discoloration efficiency and good cyclic stability, but its optical modulation range is relatively small, and the preparation process is more complicated. In order to solve the defects of the NiO film prepared by the two step method, the NiO film was prepared directly by adding oxidant to the chloride base ionic liquid. The NiO film has a relatively large optical modulation range, reached 67% at 550nm, and the preparation process is simple. It has good memory performance and good cyclic stability.
TiO2/NiO nuclear shell nanorod array films are prepared by water heat and chemical bath deposition. Compared with pure NiO nanoscale film, the nanorod array of nuclear shell structure is beneficial to electron transport and ion diffusion, with large optical modulation range, high discoloration efficiency and good cyclic stability. Electrophoretic deposition and chemical bath are used. The NiO/ graphene composite film has been prepared by the deposition method. Due to the good electronic conductivity of graphene and the larger gap of the composite film, it is convenient for the permeation of electrolyte and the transmission of electrons. It has better electrochemical activity and reversibility of the reaction. Compared with the NiO film, the NiO/ graphene composite film has a higher discoloration efficiency. The fast electrochromic speed and good cycling stability indicate that composite material is an effective way to improve electrochromic properties.
W03 nanoscale, nanoclusters, nanoscale and nanowire films are prepared by hydrothermal and solvothermal methods. The porous structure W03 nanoscale grown on FTO conductive substrates by hydrothermal method can provide more active area and facilitate ion diffusion for electrochemical reaction. It has good electrochemistry and electrochromic properties. Compared with different pH The prepared W03 nanometers and nanometers, W03 nanoscale films have high discoloration efficiency, faster electrochromic speed, greater optical modulation range and better cyclic stability. W03 nanowires and nanowire films have been grown on FTO substrates by solvothermal method. The electrochromic properties of both visible and infrared regions are very prominent. In particular, the optical modulation of W03 nanowires and nanowires in the range of -0.7 to 1.0V is 66.5% and 66% at 633nm, respectively 73.8% and 53.9% at 2000Nm, 57.7% and 51.7% at 8 mu m respectively, and the color and fading time are 4.6/3.6s and 2.0/3.4s respectively, and the discoloration efficiency is 126 and 120cm2C-1 respectively, after 4500 cycles of optical modulation. The ranges are 77.5% and 81.7%. of optical modulation range respectively.
Ti doped W03 thin films with different concentrations are prepared by hydrothermal reaction. Doping low concentration Ti in W03 film not only reduces the crystallinity of W03 thin films, but also improves the micromorphology of W03 thin films, forming a large pore star structure, providing more paths for ion diffusion and migration, with greater optical modulation range and faster electrochromism. TiO2/WO3 nuclear shell nanorod arrays were prepared on FTO glass substrate by water heat and electrodeposition, with single crystal Ti02 nanorods as core and amorphous W03 as shell structure to improve the electrochromic and electrochemical stability of the material. Compared with WO3 thin film, the TiO2/WO3 nuclear shell nanorod array The column has larger optical modulation, faster electrochromic speed, higher discoloration efficiency and excellent cycle stability.
TiO2/PANI and WO3/PANI nuclear shell nanostructure films are prepared by combining hydrothermal, solvent heat and electropolymerization. The structure of metal oxide /PANI nuclear shell nanoarrays has a multi color change effect. The material is changed from one to another in purple, green, yellow and blue. The metal oxide (?) PANI nuclear shell nanoarray has a relatively large optical modulation. The system has high color changing efficiency and excellent cycling stability.
【学位授予单位】：浙江大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TB383.2

【共引文献】