钨掺杂热致变色光学薄膜研究

VIP免费

3.0 高德中 2024-11-19 9 4 2.06MB 47 页 15积分

侵权投诉

摘要

智能窗是一种可以根据外界温度的变化情况来调节自身光透过率的窗户。智

能窗可以通过在玻璃上镀上一层热致变色薄膜来实现，随着外部环境的改变，薄

膜的光学性质也会发生改变。在热致变色薄膜材料中，最具有代表性的材料就是

二氧化钒薄膜材料，它会从低温时的半导体态相变到高温时的金属态，发生相变

的温度约为 68℃，与此同时，光透过率和光反射率会发生突变，突变速率达到皮

秒量级，且这种突变是可逆的。研究发现，在二氧化钒中掺入钨元素后，可以显

著地降低它的相变温度，这就使得钨掺杂二氧化钒热致变色光学薄膜能够应用于

智能窗玻璃材料上，使得二氧化钒作为智能窗材料具有广阔的应用前景。

本文提出了 VO2薄膜的变温光学模型，采用薄膜矩阵计算理论和修正的

Sellmeier色散模型建立了 VO2薄膜的红外光学模型。基于这种模型分析计算了 VO2

薄膜的光学特性，得到了透过率-波长曲线，并与磁控溅射法制备得到的薄膜样品

进行比较，两者的结果较为一致。接着研究了薄膜厚度对薄膜性能的影响，结果

表明，随着薄膜厚度的增加，VO2薄膜的透过率会降低，热滞回线温宽会变宽，

光密度差量OD 会增大，相变温度 Tc则会降低，这主要是受 VO2薄膜的结晶性所

致。

本文为解决 VO2薄膜相变温度过高，热滞回线温宽过大以及掺杂后红外透过

率变低等问题，开展了低成本钨钒共溅热致变色薄膜制备工艺的探索。先在室温

条件下采用磁控共溅射的方法在玻璃基片上制备得到含钨量为 1.4%的金属薄膜，

再在空气中采用后退火工艺使金属薄膜充分氧化为热致变色薄膜。对薄膜样品的

物理结构和光学性能进行了分析，发现钨钒共溅热致变色薄膜中主要由 VO2和W6+

构成，伴随少量的 V2O5以及其他钨钒化合物；钨钒共溅没有改变 VO2薄膜在玻璃

表面择优取向生长，但显著改变了 VO2薄膜的表面形貌特征。观察到钨钒共溅热

致变色薄膜的相变温度较普通 VO2薄膜从 68℃降低至 40℃，热滞回线温宽由 6℃

缩小为 3℃，低温半导体相的红外透过率分别为 62%和57%。结果表明，钨钒共溅

可达到相变温度降低，热滞回线温宽变窄，掺杂前后红外透过率变化不大之目的。

关键词：二氧化钒共溅射薄膜红外智能窗

ABSTRACT

The „smart window‟ is a certain glass that can adjust its infrared transmittance

according to the outdoor temperature. The „smart window‟ can be achieved by coating a

piece of thermochromic thin films whose optical properties will be changed with the

variety of the environment. In this kind of thermochromic material, vanadium dioxide

(VO2) is the most representative one which is able to transit phase at about 68℃，from

semi-conductor phase at low temperature to metallic phase at high temperature. At the

same time, the transmittance and reflectance of the thin films will mutate at the order of

picoseconds, and this process is reversible. It is researched that after doping tungsten(W)

in the VO2, the phase transition temperature of the thermochromic thin films will be

decreased significantly. Then it is possible that the W-doped VO2 thermochromic thin

films can be applied on the smart window materials which have a board application

prospect.

The thesis proposed a optical model of vanadium dioxide thin film, which was

built by the calculation of the theory about film matrix and modified Sellmeier

dispersion model. Based on this kind of model, the optical properties of VO2 thin films

were calculated and the transmittance-wavelength curve were acquired. We compared

this curve to the experiment data which showed the same result. Then the affect of the

film thickness on the film properties were studied, the results showed that the

transmittance of VO2 film reduced, thermal hysteresis loop wide and the optical density

changed and the phase transition temperature increased with the film of thickness

increasing. This is due to crystal imperfection of the thin film.

Tungsten-vanadium (W-V) co-sputtered thermochromic thin film at a low-cost was

designed in order to solve the problems of pure VO2 thin films including high phase

transition temperature, broad width of thermal hysteresis loop and lower infrared

transmittance after being doped. The metal thin films of 1.4% tungsten concentration

were prepared on the glass substrates by magnetron co-sputtering at room temperature,

then the prepared metal thin films were sufficiently oxidized to the thermochromic thin

films by annealing under the air condition. The structure and morphology of the samples

collected from the prepared thin films were analyzed by XPS, XRD and SEM, which

showed that W-V co-sputtered approach did not modify the preferred orientation growth

of VO2 thin films on glass substrates, but significantly changed the surface

III

morphologies of VO2 thin films. While the optical properties of W-V co-sputtered thin

films were compared with that of VO2 thin films by spectrophotometer, the phase

transition temperature dropped from 68℃to 40℃, the width of thermal hysteresis loop

narrowed from 6℃ to 3℃, and the infrared transmittances at low temperature were

62% and 57%, respectively. Results demonstrated W-V co-sputtered approach had

reduced the phase transition temperature, limited the thermal hysteresis loop and gently

changed the infrared transmittance.

Key words: VO2, co-sputtered, thin films, infrared, smart windows

摘要

ABSTRACT

第一章绪论 ......................................................................................................................... 1

§1.1 引言 ........................................................................................................................... 1

§1.2 国内外研究现状 ...................................................................................................... 3

§1.3 热致变色薄膜的应用............................................................................................... 5

§1.4 课题研究目的和意义 .............................................................................................. 6

§1.5 课题研究的创新点 .................................................................................................. 6

§1.6 本章小结 ................................................................................................................... 7

第二章钨钒共溅热致变色薄膜的理论分析 ................................................................... 8

§2.1 光学特性理论分析 ................................................................................................... 8

§2.1.1 薄膜矩阵计算理论 ........................................................................................... 8

§2.1.2 变温光学模型 ................................................................................................. 10

§2.1.3 光学特性数值计算 ..........................................................................................11

§2.2 相变机理分析......................................................................................................... 13

§2.3 本章总结 ................................................................................................................. 15

第三章钨钒共溅热致变色薄膜的制备 ......................................................................... 16

§3.1 热致变色薄膜制备方法概述................................................................................ 16

§3.1.1 反应溅射法 ..................................................................................................... 16

§3.1.2 真空蒸发法 ..................................................................................................... 16

§3.1.3 溶胶-凝胶法 .................................................................................................... 17

§3.1.4 脉冲激光沉积法 ............................................................................................. 17

§3.2 磁控溅射简介和原理 ............................................................................................ 18

§3.3 磁控溅射法制备钨钒共溅热致变色薄膜 ........................................................... 20

§3.3.1 钨钒共溅热致变色薄膜制备的工艺流程 ................................................... 20

§3.3.2 典型工艺参数 ................................................................................................. 22

§3.4 影响钨钒共溅热致变色薄膜的因素 ................................................................... 23

§3.4.1 溅射时工作压力对薄膜的影响 .................................................................... 23

§3.4.2 溅射功率对薄膜的影响 ................................................................................. 23

§3.4.3 沉积时间对薄膜的影响 ................................................................................. 24

§3.4.4 退火温度和退火时间对薄膜的影响 ............................................................ 24

§3.5 本章总结 ................................................................................................................. 25

第四章钨钒共溅热致变色薄膜的特性测试与分析 .................................................... 26

§4.1 钨钒共溅热致变色薄膜特性分析 ....................................................................... 26

§4.1.1 XPS 分析 .......................................................................................................... 26

§4.1.2 XRD 分析 ......................................................................................................... 28

§4.1.3 SEM 分析 ......................................................................................................... 29

§4.3 钨钒共溅热致变色薄膜光学特性分析 ............................................................... 31

§4.3.1 光学测试仪器与平台 ..................................................................................... 31

§4.3.2 薄膜光学特性测试与分析 ............................................................................ 33

§4.4 本章总结 ................................................................................................................. 35

第五章全文总结 ............................................................................................................... 36

参考文献 ............................................................................................................................. 38

在读期间公开发表的论文和承担科研项目及取得成果 .............................................. 43

致谢.................................................................................................................................. 45

文档加载中……请稍候！
如果长时间未打开，您也可以点击刷新试试。

下载文档到电脑，查找使用更方便

15 积分 4人已下载

立即下载 VIP免费下载

摘要：

I摘要智能窗是一种可以根据外界温度的变化情况来调节自身光透过率的窗户。智能窗可以通过在玻璃上镀上一层热致变色薄膜来实现，随着外部环境的改变，薄膜的光学性质也会发生改变。在热致变色薄膜材料中，最具有代表性的材料就是二氧化钒薄膜材料，它会从低温时的半导体态相变到高温时的金属态，发生相变的温度约为68℃，与此同时，光透过率和光反射率会发生突变，突变速率达到皮秒量级，且这种突变是可逆的。研究发现，在二氧化钒中掺入钨元素后，可以显著地降低它的相变温度，这就使得钨掺杂二氧化钒热致变色光学薄膜能够应用于智能窗玻璃材料上，使得二氧化钒作为智能窗材料具有广阔的应用前景。本文提出了VO2薄膜的变温光学模型，采用薄...

展开>> 收起<<

钨掺杂热致变色光学薄膜研究.pdf

共47页,预览5页

还剩页未读，继续阅读

钨掺杂热致变色光学薄膜研究

相关推荐

开通VIP享超值会员特权

作者详情

相关内容

推荐作者

热门标签

举报选择: