氧化铑变色薄膜的制备及其电变色研究

采用溶胶-凝胶方法制备了氧化铑电致变色薄膜。通过施加阴极或阳极电位, 薄膜在碱性电解液中呈现从亮黄（还原态）到深绿（氧化态）的可塑颜色变化,而 且可达到上千次循环而性能不变。采用XRD,SEM,TG,DTA,UVV,FTIR和循环伏安 等技术对薄膜的晶态、形貌、热处理过程和电变色过程进行了研究。得出100 ℃处 理的膜内含有一定量的结晶水,其性能最好。对薄膜的电致变色性能如：着色效率 、响应时间及循环寿命、开路记忆等进行了测试,并讨论了氧化铑薄膜电变色的反 应机理。     

Ag/WO3纳米复合膜的制备及其电致变色性质和器件的研究

通过真空镀膜方法制备的纳米Ag薄膜均匀致密, 表面光滑. 然后通过电化学方法在Ag纳米薄膜上沉积一层三氧化钨(WO3), 制备纳米Ag/WO3复合膜. 并在此基础上构筑五层式玻璃/ITO/纳米Ag-WO3复合膜/固态电解质/聚(3-甲基噻吩)/ITO/玻璃电致变色器件. 实验结果表明, 与传统的WO3膜相比, 纳米Ag/WO3复合膜具有更好的电化学活性、更高的对比度、更短的响应时间, 以及更好的稳定性. 由该复合膜组装的电致变色器件工艺简单, 电致变色性能良好.     

聚苯胺衍生物电致变色薄膜的制备与物性研究

采用循环伏安电化学沉积方式分别制备了聚邻甲氧基苯胺(1)和聚邻甲氧基苯胺/邻硝基苯胺(2)电致变色薄膜, 并通过UV-Vis、分光光度仪、场发射扫描电子显微镜(SEM)对其进行性能表征. 结果显示: 变色膜1在不同电压下能实现湖绿色(U＝－0.5 V)和淡紫色(U＝0.9 V)变化, 响应时间约15 s, 最大透光率变化(DT_max)约10% (500 nm)|变色膜2在不同电压下能实现橄榄绿色(U＝－0.9 V)和深酞蓝色(U＝1.4 V)变化, 响应时间约2 s, 最大透光率变化(DT_max)约为20% (497 nm)|SEM测试得到薄膜2的厚度约550 nm, 且不同颜色状态下其表面形貌及导电性能有较大的差别. 由以上结果可以看出: 电致变色薄膜2比1具有更快的响应速度和较好的颜色对比度, 因此薄膜2是更好的电致变色材料.     

V2O5电致变色薄膜的Raman光谱

近年来,通过向过渡金属氧化物薄膜注入Ｌｉ 制作可调节光透过率的电变色器件已越来越引起广泛的重视[1、2].由于Ｖ2Ｏ5薄膜的稳定性差,限制了它在实际中的应用.因此,为了获得变色效率高、稳定性和可逆性能好的Ｖ2Ｏ5薄膜,使用了多种制备方法,如磁控溅射法[3、6]、电化学沉积法[7、8]、溶胶凝胶法[9、10]、旋涂法[11、12]、真空蒸镀法[13、14]等.但是,无论那种方法都要解决Ｖ2Ｏ5本身在Ｈ2Ｏ或醇等的电解质溶液中电致变色时的溶解问题,通常采用控制薄膜的沉积温度或者退火处理来提高薄膜的电致变色性能[3、4、11].为了探明薄膜结构与电致变色…     

获得高性能电致变色薄膜的ITO表面修饰方法

氧化铟锡玻璃(ITO)以其优良的导电性能和透过率以及相对低的反应活性使其在显示器和电致变色器件中有广泛的应用. 然而, ITO表面的金属氧化物基团也带来了一些问题, 如通过物理方法沉积的电致变色薄膜易从ITO基底上脱离, 从而降低器件寿命, 此种问题在使用液体电解质时显得尤为突出. 为此, 我们利用有机酸小分子对ITO基底表面进行修饰, 继而利用电化学沉积的方法制备聚3,4-(2,2-二甲基丙烯二氧基)噻吩电致变色薄膜. XPS结果表明基底与修饰物间以化学键结合, 超声波处理可以看出电致变色薄膜在修饰后的基底上有更好的稳定性. 本研究提供了一种简单易行的方法来获得高性能的高分子电致变色薄膜.     

热处理对WO3纳米薄膜结构及其气致变色性能的影响

以钨粉和过氧化氢溶液为原料, 采用溶胶凝胶法制备了WO3溶胶, 并结合提拉镀膜法, 分别在普通玻璃载玻片和抛光硅片上制备了掺钯气致变色WO3纳米结构薄膜; 并分别在50, 150, 250, 350和450 ℃的空气氛围中对薄膜进行了热处理. 采用IR、双椭圆偏振光谱仪、AFM和XRD分析了薄膜的性质和微观结构, 观察了薄膜的表面形貌, 根据所得数据讨论了不同热处理温度对薄膜的结构和气致变色性能的影响.     

多钼酸盐–柠檬酸复合膜的多色光致变色

制备了多钼酸盐–柠檬酸光致变色复合膜，紫外光照后发现不同摩尔比的复合膜呈现不同的颜色。当摩尔比为1.0，0.3和0.2时，变色后的薄膜分别显深蓝色，深黄褐色和淡海绿色。通过对薄膜的拉曼光谱分析证实呈现不同的颜色是由于在变色后的膜中生成了不同的物种。柠檬酸在光致变色过程中起着重要的作用, 在紫外光的照射下它作为空穴的捕获剂, 抑制了光生电子和空穴的复合, 使多钼酸盐呈现紫外光致变色现象。     

MoO_3电致变色薄膜的XPS研究

近年来 ,随着人们提倡节能和使用洁净能源 ,无机电致变色材料在建筑物采光控制系统和反射率可调表面的应用研究 ,已成为材料领域的一个新热点 .WO3、 MoO3等过渡金属氧化物薄膜具有良好的电致变色效应 ,是人们研究的重点 .其中 MoO3的电致变色效果要好于 IrO2、 TiOx、 CoO及 NiOx等电致变色材料 [1],而且它在可见光区有比 WO3更柔和的色彩 ,使人眼更易于适应其颜色变化 .着色态的 MoO3称为钼青铜 ,其开路记忆也好于钨青铜 [2].故 MoO3电致变色薄膜是极有潜力用于实用化的电致变色器件 .MoO3薄膜常用的制备方法有真空蒸 发、化学气…     

WO3/4,4′-联苄胺光致变色超晶格薄膜的研究

无机-有机超晶格薄膜材料的制备以及性质研究是目前国际上的研究热点.基于超分子化学自组装原理,利用自组装技术构建含有有机分子的光致变色纳米超晶格薄膜材料,是一种研制光致变色功能薄膜材料的新方法.此项研究能够为研制变色响应速度快的、稳定性好的、变色可调控的光致变色器件奠定基础,具有深远的意义和重要的科学价值.本文采用溶液中相反电荷聚电解质自组装的方法(PEs法)[1],制备了WO3/4,4′-联苄胺超晶格薄膜;采用紫外可见吸收光谱和小角X-射线衍射谱对薄膜的层状结构和分子的排列方式进行了研究.     

原位聚合沉积聚苯胺薄膜及其电致变色性能

采用原位聚合的方法,以水溶性高分子聚乙烯吡咯烷酮(PVP)为空间稳定剂,直接在玻璃基体表面聚合沉积导电聚苯胺(PANI)薄膜。用扫描电镜(SEM)、紫外可见光谱(UV-Vis)、四探针电导率测试仪和热重分析仪(TG)对聚苯胺膜结构及性能进行了表征。采用循环伏安法测试了薄膜的电致变色性。结果表明:盐酸掺杂聚苯胺薄膜呈翠绿色,薄膜厚115 nm,表面电导率为4.6×10-3S/cm。电致变色实验中聚苯胺电极电位在-6~ 6 V循环变化时,薄膜颜色在黄绿和蓝绿间可逆变化。电致变色前后聚苯胺薄膜的紫外可见吸收光谱表明,随着电极电位的降低,极化子峰发生红移,说明聚苯胺分子链中醌式结构单元被还原,聚苯胺薄膜质子化程度提高。     

Electrochromic NiOxHy,hydrated films: cyclic voltammetry and ac impedance spectroscopy in aqueous electrolyte

The characteristics of the electrochromic process of sputtered hydrated nickel oxide films have been investigated by cyclic voltainmetry, in situ optical transmittance and ac impedance spectroscopy. The results indicate that the state of coloration of these films is related to the conditions used to drive the electrochromic process, whose kinetics at high positive potentials become controlled by ion diffusion into and from the nickel oxide structure.     

Electrochromic Properties of Rhodium Oxide Films Prepared by Sol-gel Method

Electrochromic materials have been extensively investigated for their significant potential in information display, automotive, sensor and smart windows^[1]. Many studies have been carried out on the inorganic electrochromic materials, such as WO₃, MoO₃, NiO_x and so on^[2]. In this paper, We first report the electrochromic behavior of rhodium oxide film prepared by sol-gel method on transparent conductor substrate. The film exhibited reversible two color (from bright yellow to dark green) electrochromic behavior with satisfactory contrast at anodic and cathodic forms when the applied potential was reversed successively.     

The influence of annealing on electrochromic properties of Al–B–NiO thin films prepared by sol–gel

Al–B–NiO thin films were prepared using the sol–gel process and deposited on Indium tin oxide (ITO)-coated glass substrates via the dip-coating technique for the purpose of developing high performance electrochromic materials. The influence of the anneal on the structural and electrochromic properties of Al–B–NiO films is reported. Thermogravimetry (TG) and differential thermal analysis (DTA), cyclic voltammetry measurements (CV), UV spectrophotometer, atomic force microscopy (AFM) and X-ray diffraction (XRD) have been used to investigate the structural and electrochromic properties. The thickness of the films was determined by spectrophotometric analysis in 350–1,000 nm wavelength. Results showed that the Al–B–NiO thin films treated at high temperature have both the excellent electrochromic properties and good reversibility. The transmittance change (ΔT) of the film treated at 500 °C reaches still ~50% at the wavelength of 550 nm. The microstructure and the surface morphology were considered to play an important role in the electrochromic properties with different temperatures.     

Synthesis and characterization of chemically grown electrochromic tungsten oxide

Tungsten oxide thin films, which are cathodic coloration materials that are used in electrochromic devices, were prepared by a chemical growth method and their electrochromic properties were investigated. The thin films of WO₃ were deposited onto electrically conducting substrates: fluorine doped tin oxide coated glass (FTO) with sheet resistance of about 10 Ω/cm. Transparent, uniform and strongly adherent thin film samples of WO₃ were studied for their structural, morphological, optical and electrochromic properties. The XRD data confirmed the monoclinic crystal structure of WO₃ thin films. The direct band gap Eg for the films was found to be 2.95 eV which is good for electrochromic device application. The electrochromism of WO₃ thin film was evaluated in 0.5 M LiClO₄/propylene carbonate for Li⁺ intercalation. Electrochromic properties of WO₃ thin films were studied with the help of Cyclic Voltammetry (CV), Chronoamperometry (CA) and Chronocoulometry (CC) techniques.     

MoO3电致变色薄膜的XPS研究

Molybdenum oxide films were fabricated successfully by spin coating from Li＋ doped peroxo polymolybdate solution via sol gel technique.Their electrochemical and electrochromic properties were investigated by cyclic voltammetry and in situ UV transmittance measurements.The results showed that the films possessed excellent electrochemical stability and reversibility.The electrochromic mechanism of the MoO3 was discussed by using results obtained from X ray photoelectron spectroscopy (XPS).The results showed that the most part of the Mo6＋ in MoO3 film was reduced to Mo5＋ and Mo4＋ ions during the Li＋ intercalation process,Mo4＋ was oxidized to Mo5＋ and part of Mo5＋ was oxidized to Mo6＋ again during the Li＋ deintercalation process.So it was considered that Mo4＋ ions existed in the colored MoO3 films.     

Electrochemical deposition of electrochromic niobium oxide films from an acidic solution of niobium peroxo complexes

Deposition of electrochromic niobium(V) oxide films from an acidic solution of niobium peroxo complexes on a transparent conducting cathode in the form of an SnO₂ film on glass was studied. With an increase in the negative potential of the deposition of niobium(V) oxide films from a solution of niobium peroxo complexes at pH 2.5, the structure and composition of the films changed. A study of the electrochromic properties of Nb₂O₅ films revealed broadening of the bands in the electrochromic coloration spectrum with an increase in the negative potential of the deposition.     

Electrochemical and Electrochromic Properties of Ni Oxide Thin Films Prepared by a Sol–Gel Method

Nickel oxide thin films, which are well known anodic coloration materials that are used in electrochromic devices, were prepared by a sol–gel method, and their electrochemical and electrochromic properties were investigated. The sol was prepared from Ni(OH)₂ powder with an average size of 7 nm, in a mixture of ethylene glycol and absolute ethanol. The films were coated on an ITO substrate using the powder, dispersed in the solution. When additive materials, acetyl acetone and glycerol, were added to the sol its hardness and adhesion properties were improved. The optimized thin film formed an amorphous, porous structure, and showed a large current density during continuous potential and pulse potential cycling. The film also was transparent and had a high coloration efficiency (33.5 cm²/C) and a rapid response time (1.0–2.5 s) during the coloring/bleaching process.     

Electrochromic smart windows: energy efficiency and device aspects

This paper covers three aspects of electrochromic smart windows. Their energy efficiency is discussed, and it is argued that a control strategy considering whether a room is in use or not can lead to large savings of the energy needed for space cooling. With regard to durability, it is shown that chemical compatibility between the electrolyte and electrochromic films of tungsten oxide and nickel oxide can be achieved without loss of optical transparency. Finally, we consider device manufacturability and present data on precharging of electrochromic nickel oxide films by ozone treatment. Electronic Publication