助剂对纳米级二氧化钛表面改性的研究

Study on the Surface Modification of Nano-sized Titanium Dioxide With Additive

采用硅烷偶联剂KH-570对两种常见光催化晶型二氧化钛表面改性,通过控制不同条件如pH值、硅烷偶联剂用量、反应温度,测量改性后二氧化钛溶液平均粒径及光催化活性,寻求最优改性条件。对于锐钛矿型二氧化钛:溶液pH值为4、10%硅烷偶联剂用量、反应温度为80℃时,硅烷偶联剂改性效果最好,最优改性条件下溶液光催化降解率为93.5%。对于金红石型二氧化钛:溶液pH值为6、10%硅烷偶联剂用量、反应温度为80℃时,硅烷偶联剂改性效果最好,在最优改性条件下光催化降解率为82.8%。通过XRD、红外光谱表征手段,观察硅烷偶联剂改性前后二氧化钛变化,可以看出硅烷偶联剂水解后附着在二氧化钛表面,使二氧化钛表面性质发生改变,但并未改变二氧化钛原本晶型。

Silane coupling agent KH-570 was used to modify the surface of two common photocatalytic crystalline titanium dioxides.By controlling different conditions including pH,amount of silane coupling agent and reaction temperature,the average particle diameter of modified titanium dioxide solution and photocatalytic activity were measured in order to seek optimal modification conditions.For anatase titanium-type titanium dioxide:when the solution pH was 4,the amount of silane coupling agent was 10%and the reaction temperature was 80℃,the modification effect of silane coupling agent was the best.Under the optimal modification conditions,the solution photocatalytic degradation rate was 93.5%.For rutile titanium dioxide:the modification effect of silane coupling agent was the best when the solution pH was 6,silane coupling agent dosage was 10%and reaction temperature was 80℃,and the photocatalytic degradation rate was 82.8%under the optimal modification conditions.Through XRD,infrared spectroscopy,and Zeta potential analysis and characterization methods,the changes of titanium dioxide before and after the modification with the silane coupling agent were observed,it can be seen that the silane coupling agent was attached to the surface of titanium dioxide after hydrolysis,which changed the surface properties of the titanium dioxide,but did not change the original titanium dioxide crystal form.