平整二钛酸钾薄膜的制备及其气相光催化活性

采用溶胶-凝胶法制备了K2Ti2O5薄膜并进行表征;在K2Ti2O5薄膜表面上形成致密的十八烷基三氯硅烷(C18H37SiCl3,OTS)单层自组装膜(SAMs);用OTS SAMs 水接触角变化研究薄膜的气相光催化活性;测量了薄膜的光电流响应.研究发现:K2Ti2O5薄膜表面平整、均匀、致密、在玻璃基片上透明;在紫外和可见光区都有光吸收;K2Ti2O5薄膜上OTS SAMs在空气中用254nm的紫外光照射时降解速度比在TiO2薄膜上快;K2Ti2O5薄膜产生阳极光电流,比TiO2薄膜具有更强的光激发和更稳定的光电流响应.结果表明,K2Ti2O5薄膜在空气中用紫外光照射能很有效的分解OTS SAMs,是一种很好的治理气相有机污染物的光催化剂.

Preparation and gaseous photocatalytic activity of smooth potassium dititanate film

A new smooth potassium dititanate film was prepared by sol-gel method.The film was characterized by TG-DSC,XRD,atomic force microscopy(AFM) and UV-Vis absorption spectra.The photocatalytic decomposition of octadecyltrichlorosilane(OTS) based self-assembled monolayers(SAMs) formed on K2Ti2O5 films was studied using contact angle analysis.The photoelectrochemical response of the film was determined by electrochemical method.It is shown that the films were smooth,compact,and transparent.Compared with TiO2 film,the K2Ti2O5 film showed a wide absorption in the ultraviolet and visible region.It is found that the monolayers on K2Ti2O5 are decomposed much faster than those on TiO2 under UV irradiation of 254nm in air.The film has a stronger photo-response and more stable anode photocurrent.The observation indicates that the K2Ti2O5 film efficiently decomposes the alkylsiloxane monolayers under UV irradiation in air and it is a good photocatalyst for gaseous organic pollutant treatment.