X光吸收光譜對鈦修飾五氧化二釩電致變色薄膜原子與電子結構之研究

Atomic and Electronic Structure of Ti-V2O5 electrochromic film studied by X-ray Absorption Spectroscopy

吳奕翰(I-Han Wu)

指導教授 ： 董崇禮

淡江大學/理學院/物理學系碩士班/碩士(2022年)

https://doi.org/10.6846/TKU.2022.00688

摘要

近年來電致變色玻璃已被廣泛的研究，在智能窗戶領域中具有優秀節能的應用實例。氧化釩(Vanadium Oxide)是個眾所皆知的變色材料，是綠色建築中非常具有前景的節能材料應用，然而此類型的材料在電致變色相關機制與微觀影響的研究已知甚少，因此本文採用溶膠凝膠法製備該薄膜。相較於其他材料，釩氧化物具有結構簡單與價格低廉的優點，且較於多彩。這種材料只需單層薄膜在玻璃上就足以有效改變玻璃光學性質。通過電子顯微鏡(SEM)、原子力顯微鏡(AFM)和X射線繞射(XRD)對薄膜進行厚度，表面形貌，晶體結構的量測。光學性質由UV-Vis分光光度計而得。電化學性能由循環伏安法(CV)、計時電流法(CA)測定。結果顯示，Ti-V2O5比V2O5顯示出較出色的著色率，可以歸因於局域原子結構的對稱性和電子結構的變化。原位吸收光譜即時觀測薄膜進行漂白與著色反應時的原子和電子結構變化，以便闡明其電致變色機制。本文還研究了對綠能窗戶應用至關重要的電致變色薄膜的化學反應穩定性。

關鍵字

五氧化二釩 ； 電化學 ； 溶膠凝膠 ； 電致變色 ； XAS ； 智能窗戶

並列摘要

In recent years, electrochromic glass has been widely studied, and it has excellent energy-saving application in the field of smart windows. Vanadium oxide is a well-known electrochromic material. However, the research on the electrochromic mechanism and microscopic effects of this type of smart material is seldom known, this study uses sol-gel method to prepare the film. Vanadium oxide systems are simple, cheap, and exhibit different colors depend on its multiple oxidation states. A single layer of this material deposited on a glass is sufficient to change the optical property of the glass efficiently. The film thickness, surface morphology, crystal structure were confirmed by scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD). Optical properties were obtained by UV-Vis spectrophotometer. Electrochemical properties were determined by cyclic voltammetry (CV) and chronoamperometry (CA). The results show that Ti-V2O5 has better coloring rate than V2O5, which can be attributed to the alternation of local atomic symmetry and electronic structures revealed by X-ray absorption spectroscopy. Moreover, in-situ XAS monitored the change of atomic and electronic structures during the bleaching-coloration to elucidate the electrochromic coloration mechanism of these films. The stability of the electrochromic film, which is critical for architectural window applications, is also investigated in this study.

並列關鍵字

Vanadium Pentoxide ； Electrochemistry ； Sol-Gel ； Electrochromism ； XAS ； Smart Window

參考文獻

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