探討自製銀修飾光觸媒對大腸桿菌的抗菌研究

Study the antibacterial activity of Ag modified TiO2 photocatalyst on Escherichia coli.

馬振瑜(Jhen-Yu Ma)

指導教授 ： 盧啟元

中山醫學大學/健康管理學院/公共衛生學系碩士班/碩士(2014年)

摘要

近幾年來，二氧化鈦因為其無毒、穩定且容易取得的優點，使之在抗菌上受到廣泛的應用，但是TiO2存有電子電洞對重組時間短以及對可見光波之吸收能力差等缺點，在研究上受到限制，為了因應這些限制，學者們利用不同的改質方法來提高TiO2之光催化活性，如提升比表面積、金屬摻雜等，因此本研究利用水熱法製備不同比例之Ti-Si光觸媒，並使用含浸法和銀-胺法對商業化光觸媒P25負載Ag金屬，以大腸桿菌（DH5α）為測試菌種，進行抗菌活性測試，擇較適之改質方法，進行Ti-Si光觸媒之Ag改質，探討Ti-Si光觸媒與P25之抗菌能力，及經Ag負載後對兩者抗菌活性之影響。
同時本研究將實驗製備之Ti-Si光觸媒以FESEM、BET、UV-Vis、XRD等儀器進行物化特性分析。在抗菌活性結果顯示，50%Ti-Si與70%Ti-Si光觸媒在UV光照射30分鐘下之抗菌效果分別為63%與64%皆高於商業化光觸媒P25（50%），且經銀負載之後，1%Ag負載30%Ti-Si光觸媒，在可見光以及紫外光下反應30分鐘之抗菌率分別為99%以及95%，改善傳統TiO2光吸收能力之限制，提升在可見光下之光催化活性，另外，本實驗製備之Ti-Si光觸媒可用可見光取代紫外光，即可在短時間內達到良好的抗菌效果。

關鍵字

二氧化鈦 ； 銀 ； 抗菌 ； 可見光

並列摘要

TiO2 has been used widely on the photocatalytic reaction due to the nontoxic, stability, and low price, in recent years. However, the study is limited by the drawbacks of TiO2 include low absorption of visible light and fast recombination of the electron-hole pairs. In order to improve the photocatalytic activity, some studies have been carried out, such as large specific surface area and metal doping on TiO2.
In this study, Ti-Si photocatalysts with different ratios of Ti/Si have been prepared by the hydrothermal method. Then, Ag/P25 catalyst has been prepared by the impregnation and Ag-NH3 method, respectively. After the antibacterial tests of E. coli (DH5α) over different Ag/P25 catalysts have been studied. The better catalyst preparation would be chosen for the preparation of Ag/Ti-Si catalysts. Final, the antibacterial ability of Ti-Si catalysts and P25 would be discussed, and the effect of doping Ag particles would be studied. The prepared photocatalysts were also characterized by the FESEM, BET, UV-Vis and XRD.
The results of antibacterial test indicate that 50%Ti-Si (63%) and 70%Ti-Si (64%) catalysts showed the better antibacterial activity than that of P25 (50%) after 30 minutes exposure by UV light. For the catalyst of 1%Ag/30%Ti-Si, the antibacterial efficiency after 30 minutes exposure by visible light and UV light is 99% and 95%, respectively. The antibacterial efficiency could be improved with Ag doping due to the good absorption of visible light whereas commercial TiO2 (P25) shows the low absorption. The experimental results indicate that the good performance of Ti-Si catalyst could be achieved after 30 min exposure by visible light instead of UV light.

並列關鍵字

TiO2 ； Ag ； Antibacterial ； Visible

參考文獻

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