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    Please use this identifier to cite or link to this item: http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/74538

    Title: 聚乙烯醇-鎢氧化物混成膜之製備與其光致變色行為
    Other Titles: Preparation of poly (vinyl alcohol)-tungsten oxide hybrid films and their photochromic behaviors
    Authors: 潘威霖;Pan, Wei-Lin
    Contributors: 淡江大學化學工程與材料工程學系碩士班
    Keywords: 鎢氧化物;光致變色;有機無機混成膜;tungsten oxide;photochromic;organic-inorganic hybrid film
    Date: 2011
    Issue Date: 2011-12-28 18:50:13 (UTC+8)
    Abstract: 本實驗利用膠體化學法與析出反應製備出PVA/WO3混成粉末,並將粉末回溶製備成PVA/WO3混成薄膜。藉由析出反應能有效提升薄膜的可見光穿透度。改變鎢氧化物於混成溶液與混成粉末中的含量,利用FTIR、XRD、SEM、TEM與紫外線-可見光光光譜儀探討其結構與光學性質的改變。
    從TEM與SEM圖得知,混成粉末中鎢氧化物以奈米級粒子分散於PVA水溶液中,尺寸大小為10~20 nm,且隨鎢酸鈉的添加量的增加,鎢氧化物粒子的尺寸會隨之增大。此外,將混成溶液於室溫下反應九天,鎢氧化物粒子會轉變為立方體的結構,且呈現部分結晶的狀態,尺寸大小為50~100 nm。
    PVA/WO3混成薄膜經紫外光線照射後,在620 nm與930 nm的位置會出現兩個吸收峰,隨鎢氧化物含量的增加,吸收峰會有增強的趨勢,但卻會隨反應天數的增加而減弱。
    In this study, PVA/WO3 hybrid powders were prepared by colloid chemistry method and a precipitation process. PVA/WO3 hybrid films were prepared using the precipitated powders. The visible transmittance of the hybrid films can be improved by means of the precipitation process of the powders. By varying the ration of Na2WO4‧2H2O:PVA in the solution, the corresponding structure and photochromic behavior of the film and powder were investigated using FTIR、XRD、SEM、TEM and UV-Vis.
    WO3 nanoparticles in the 10~20 nm range have been observed in TEM and SEM images. From the observation by TEM, it was found that with the increase of the amount Na2WO4‧2H2O, the size of WO3 nanoparticle was obviously increased. WO3 nanoparticles became cubic nanocrystal with a length of 50~100 nm after aging of 9 days at room temperature.
    When the hybrid films were irradiated by UV light, two absorption peaks appeared at about 620 nm and 930 nm in the UV-Vis spectra. The absorption intensity increasing the concentration of Na2WO4‧2H2O and decreased with increasing the aging time.
    Appears in Collections:[Graduate Institute & Department of Chemical and Materials Engineering] Thesis

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