以超音波輔助浸鍍法製備TiO2薄膜與光觸媒改質特性之研究
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2015
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本研究以超音波輔助浸鍍法(ultrasonic–assisted dip coating)在玻璃基材上製備二氧化鈦(titanium dioxide, TiO2)薄膜。利用光譜儀、XRD、HR-FESEM等儀器進行量測並分析鍍液濃度、浸鍍次數與退火溫度等製程參數對於薄膜結構與特性的影響。接著利用接觸角量測儀以照光前後接觸角度變化量去篩選出最佳製程參數以作為後續光觸媒改質實驗的樣本。最後被選出的最佳製程參數樣本以硝酸鋰、硝酸鈉與硝酸鉀進行改質，並在不同照光波長之下進行甲基藍光催化降解實驗以評估改質TiO2薄膜的光觸媒性能。實驗結果顯示，退火溫度400°C以上即可成功製備具有銳鈦礦結構之TiO2薄膜。TiO2薄膜的光譜紅位移現象隨著浸鍍次數增加而增強。經由硝酸鋰、硝酸鈉改質試片於紫外光波長照射之後，其接觸角最佳可達8.04°，且改質後試片以可見光波長照射後仍可產生光催化反應並縮短能隙。改質試片於紫外光與可見光照射下均可提升光催化降解甲基藍的能力，其中以硝酸鋰改質具有最佳的效果。經硝酸鋰改質於紫外光與可見光照射下對甲基藍降解效能分別可提升15.88%與9.19%。
In this study, the titanium dioxide (TiO2) thin film was prepared on glass substrate by using ultrasonic-assisted dip coatingmethod. The structure and characteristics of TiO2 thin film were measured by using spectrometer, XRD, HR-FESEM and other suitable equipment; to analysis the relationship between process parameters (concentration of coating solution, dip-coating times, and annealing temperature) and characteristics of TiO2 thin film. Then, the optimal process parameter was determined by a contact angle instrument to measure contact angle variation before and after irradiation, and was adopted in the modified photocatalyst experiments. The samples with optimal process parameter were modified with lithium nitrate (LiNO3), sodium nitrate (NaNO3), and potassium nitrate (KNO3); then their photocatalyst performance of TiO2 thin film was tested by the photocatalytic degradation of methylene blue under different irradiation wavelengths. The results show that the annealing temperature above 400 °C can be successfully prepared the TiO2 thin film with anatase structures. Spectral red shift of TiO2 thin film is enhanced with increasing dip-coating times. The minimum contact angle of modified samples with LiNO3 and NaNO3 can reduce to 8.04° after ultraviolet irradiation, and the modified samples still perform photocatalysis reaction and shorten the band gap under irradiation of visible light. The modified samples under irradiation of ultraviolet or visible light can improve the photocatalytic degradation performance for methylene blue. Among them, the modified samples with LiNO3 have the optimal performance. The modified sample with LiNO3 under irradiation of ultraviolet and visible light can improve the degradation performance of methylene blue of 15.88% and 9.19%, respectively, compared with the non-modified sample.
In this study, the titanium dioxide (TiO2) thin film was prepared on glass substrate by using ultrasonic-assisted dip coatingmethod. The structure and characteristics of TiO2 thin film were measured by using spectrometer, XRD, HR-FESEM and other suitable equipment; to analysis the relationship between process parameters (concentration of coating solution, dip-coating times, and annealing temperature) and characteristics of TiO2 thin film. Then, the optimal process parameter was determined by a contact angle instrument to measure contact angle variation before and after irradiation, and was adopted in the modified photocatalyst experiments. The samples with optimal process parameter were modified with lithium nitrate (LiNO3), sodium nitrate (NaNO3), and potassium nitrate (KNO3); then their photocatalyst performance of TiO2 thin film was tested by the photocatalytic degradation of methylene blue under different irradiation wavelengths. The results show that the annealing temperature above 400 °C can be successfully prepared the TiO2 thin film with anatase structures. Spectral red shift of TiO2 thin film is enhanced with increasing dip-coating times. The minimum contact angle of modified samples with LiNO3 and NaNO3 can reduce to 8.04° after ultraviolet irradiation, and the modified samples still perform photocatalysis reaction and shorten the band gap under irradiation of visible light. The modified samples under irradiation of ultraviolet or visible light can improve the photocatalytic degradation performance for methylene blue. Among them, the modified samples with LiNO3 have the optimal performance. The modified sample with LiNO3 under irradiation of ultraviolet and visible light can improve the degradation performance of methylene blue of 15.88% and 9.19%, respectively, compared with the non-modified sample.
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超音波輔助法, 浸鍍法, 二氧化鈦薄膜, 光觸媒改質, 光催化特性, ultrasonic-assisted, dip coating, TiO2 thin films, modified photocatalyst, photocatalytic properties