以旋鍍法製備二氧化鈦薄膜及特性研究

Abstract

本研究使用溶膠-凝膠法製備以過氧鈦酸（Peroxotitanic, PTA）為基底的二氧化鈦 （Titania, TiO2）光觸媒材料 ，並使用二階製程法調配不同濃度的PTA鍍液，以旋轉塗佈法成膜至玻璃試片上，經高溫燒結後形成 TiO2薄膜。藉由濃度比例、旋鍍次數與燒結溫度的參數調變，探討實驗參數對 TiO2薄膜結構與特性的影響。利用XRD、FESEM、UV/VIS/NIR光譜儀等精密儀器進行量測並分析製程參數與薄膜特性的關係，篩選出較佳實驗參數，作進一步光催化特性研究。針對篩選結果進行光催化水接觸角及亞甲基藍降解實驗，配合光譜儀作定量分析 ，探討鍍膜試片之光學、親疏水性與光催化降解汙染物特性。實驗結果顯示，本研究成功製備出具光催化性銳鈦礦相之 TiO2薄膜，薄膜品質平整無龜裂且結晶性良好，隨著鍍膜次數及燒結溫度增加，結晶顆粒變大且更緻密。由薄膜之光學特性顯示，具有較空白玻璃為低的穿透率與高反射特性，於紫外線波段之最低相對穿透比值達0.35，平均反射率為20%以上，適合應用在節能玻璃材料。光催化實驗方面，證實本研究之 TiO2薄膜具備光致親水特性及光催化降解汙染物能力，最佳接觸角可達18.48度，扣除亞甲基藍本身光解率後，薄膜之最佳降解率為25.2%。未來將利用此材料之最佳參數，應用於節能玻璃或太陽能電池等高平整性相關產品。In this study, sol-gel method was used to fabricate Peroxotitanic-acid (PTA) based Titania (TiO2) material. A two-step process was employed to deploy PTA with different concentrations, which were then deposited on a test glass by using spin-coating. After high-temperature sintering, a TiO2 thin film was then formed. Through tuning the parameters of proportions of the concentration, times of the spin-coating, and the changes of sintered temperature, the effect of experimental parameters on the TiO2 thin film structures and characteristics were investigated. XRD, FESEM, UV/VIS/NIR spectrometers, and other sophisticated instruments were utilized for measurement and analysis of the relationship between process parameters and film characteristics. Preferred experimental parameters were then selected for further study of photocatalytic characteristics. The screened results were employed for photocatalytic water contact angle and Methylene Blue (MB) experiments; with the use of spectrometer for quantitative analysis of the sample, the optical, hydrophobic/philic, and photocatalytic degradation pollutants characteristics were investigated. Experimental results showed that the photocatalytic TiO2 thin film of anatase was successfully fabricated with smooth, no cracks, and great crystallinity properties. Furthermore, as the number of coating and sintering temperature increased, the crystal grains became larger and more condensed. The thin film displayed optical characteristics of lower transmittance and higher reflectance comparing to un-coated glass; furthermore, its lowest relative transmittance in UV range was 0.35, and its average reflectance was more than 20%. All these verified its availability for energy saving glass applications. Finally, this study confirmed that TiO2 thin film has a hydrophilic characteristic and a characteristic of photocatalytic degradation of pollutants, where the best contact angle is up to 18.48°, and the best degradation of MB is 25.2%. In the future, the optimum parameters of this material are expected to be used for high-level-related products including energy saving glass or solar cell.