Zhang Buyue, Wang Jintao, Jiang Shuhui, Yuan Meng, Chen Xinyu
School of Physics, Changchun University of Science and Technology, Changchun 130012, China.
School of Infromation Engineering, Yantai Institute of Technology, Yantai 261499, China.
Micromachines (Basel). 2024 Dec 5;15(12):1473. doi: 10.3390/mi15121473.
Tungsten oxide (WO) electrochromic devices are obtaining increasing interest due to their color change and thermal regulation. However, most previous work focuses on the absorption or transmission spectra of materials, rather than the optical parameters evolution in full spectrum in the electrochromic processes. Herein, we developed a systematic protocol of ex situ methods to clarify the evolutions of subtle structure changes, Raman vibration modes, and optical parameters of WO thin films in electrochromic processes as stimulated by dosage-dependent Li insertion. We obtained the below information by ex situ spectroscopic ellipsometry. (1) Layer-by-layer Li embedding mechanism demonstrated by individual film thickness analysis. (2) The details of its optical leap in the Brillouin zone in the full spectral. (3) The optical constants varied with the Li insertion in the ultraviolet, visible, and near-infrared bands, demonstrating the potential for applications in chip fabrication, deep-sea exploration, and optical measurements. (4) Simulated angular modulation laws of WO films for full spectra in different Li insertion states. This ex situ method to study the optical properties of electrochromic devices are important for monitoring phase transition kinetics, the analysis of optical leaps, and the study of ion diffusion mechanisms and the stoichiometry-dependent changes in optical constants over the full spectral. This work shows that electrochromic films in Li surface permeation can be applied in the field of zoom lenses, optical phase modulators, and other precision optical components. Our work provides a new solution for the development of zoom lenses and a new application scenario for the application of electrochromic devices.
氧化钨（WO）电致变色器件因其颜色变化和热调节功能而越来越受到关注。然而，以往的大多数工作都集中在材料的吸收或透射光谱上，而不是电致变色过程中全光谱范围内光学参数的演变。在此，我们开发了一套系统的非原位方法协议，以阐明在剂量依赖性锂插入刺激下，WO薄膜在电致变色过程中细微结构变化、拉曼振动模式和光学参数的演变。我们通过非原位光谱椭偏仪获得了以下信息：（1）通过单个薄膜厚度分析证明的逐层锂嵌入机制；（2）其在全光谱布里渊区的光学跃变细节；（3）光学常数在紫外、可见和近红外波段随锂插入而变化，展示了在芯片制造、深海探测和光学测量中的应用潜力；（4）不同锂插入状态下WO薄膜全光谱的模拟角度调制规律。这种研究电致变色器件光学性质的非原位方法对于监测相变动力学、分析光学跃变、研究离子扩散机制以及全光谱范围内光学常数随化学计量比的变化具有重要意义。这项工作表明，锂表面渗透的电致变色薄膜可应用于变焦镜头、光学相位调制器等精密光学元件领域。我们的工作为变焦镜头的发展提供了一种新的解决方案，也为电致变色器件的应用提供了一种新的应用场景。
