【作者】 翟东；

【导师】 张卫国；

【作者基本信息】 天津大学 ， 应用化学， 2009， 硕士

【摘要】 论文采用阳极氧化法在钛片上制备了排列规则、垂直生长的二氧化钛纳米管阵列,最佳制备工艺为:氧化电压20V,反应时间30min,HF电解液浓度0.8wt%。扫描电镜（SEM）下观察到,TiO₂纳米管内径约85 nm,壁厚约10 nm,长约1.5μm。采用敏化和活化工艺,在超声场下制备出金属Pd修饰TiO₂纳米管阵列,采用SEM、透射电子显微镜（TEM）和多种电化学测试技术考察了超声时间和超声功率对纳米管阵列形貌、结构及其光电性能的影响。结果表明,超声时间和超声功率是制备金属Pd修饰二氧化钛纳米管阵列的关键因素;最佳制备工艺为:超声时间15min,超声功率60%。通过SEM及TEM可以观察到单根TiO₂纳米管及沉积在纳米管中的金属Pd,并通过TEM能谱加以确认纳米管中金属Pd。选取具有代表性的难降解染料罗丹明B为目标物质,以8W紫外灯为光源,考察了不同条件下所制备金属Pd修饰二氧化钛纳米管阵列电极对罗丹明B的光电催化性能。采用恒电位沉积方法制备了Cu2O修饰二氧化钛纳米管阵列,通过阴极极化曲线确定沉积电位为-0.3V。采用SEM、X射线粉末衍射（XRD）和多种电化学测试技术考察了电沉积时间和电解液组成对纳米管阵列形貌、结构和光电响应性能的影响。SEM表征检测表明:电沉积10s和20s的纳米管均没有被沉积的Cu2O封闭;XRD结果表明:电解液中Cu2+离子浓度为0.4mol/L,电沉积时间为20s所制备纳米管的Cu2O的特征衍射峰最为明显。光电性能测试结果表明,电解液中Cu2+离子浓度为0.4mol/L,电沉积时间为20s时所制备纳米管的光电响应最大,光照下电极电化学反应电阻值最小。由上述检测得到最佳制备工艺为:电沉积时间20s,电解液中Cu2+离子浓度为0.4mol/L。考察了不同条件下所制备Cu2O修饰二氧化钛纳米管阵列电极对罗丹明B的光电催化性能。光电催化实验表明,金属修饰TiO₂纳米管阵列电极对罗丹明B的降解效率比TiO₂纳米管有了明显的提高,对罗丹明B显示出了良好的降解效果。更多还原

【Abstract】 TiO₂ nanotube arrays were successfully fabricated by andization method on a pure titanium sheet. The optimal reaction conditions were as follows: 20V for oxidation potential, 30minutes for reaction time and 0.8wt% for HF electrolytes concentration. The results of SEM measurements showed that the inner diameter was about 85nm, the wall thickness 10nm and length 1.5μm.Metal Pd modified TiO₂ nanotube arrays were fabricated by sensitization and activation technology in the ultrasound field. The influencing factors of ultrasonic time and ultrasonic power on the morphology, structure and photoelectrochemistry properties of nanotube arrays were investigated with SEM, transmission eletron microscopy （TEM） and various electrochemical measurements. The results show that ultrasonic time and ultrasonic power were key factors to form metal Pd modified TiO₂ nanotube arrays; and the optimal reaction conditions were as follows:15min for ultrasonic time , 60% for ultrasonic power. A single TiO₂ nanotube and metal Pd deposited on the nanotube were observed by SEM and TEM, and Pd could be confirmed through TEM spectroscopy. The degradation of rhodamine B was employed as the model reaction to evaluate the photoeletrocatalytic activity of metal Pd modified TiO₂ nanotube arrays under the 8W ultraviolet.Cu2O modified TiO₂ nanotube arrays were fabricated through potentiostatic method, and -0.3V for deposition potential could be confirmed through cathodic polarization curve. The influencing factors of electrodeposition time and electrolyte composition on the morphology, structure and photoelectrochemistry properties of nanotube arrays were investigated with SEM, X-ray diffraction （XRD） and various electrochemical measurements. The results of SEM characterization of the test show that nanotube arrays fabricating by 10s and 20s electrodeposition times were not closed by deposition of Cu2O; The results of XRD show that characteristic diffraction peaks of Cu2O in the nanotube preparing by 0.4mol/L for Cu2+ concentration in the electrolyte and 20s for electrodeposition time can be oberved obviously.The results of photoelectric response shows that nanotube arrays preparing by 0.4mol/L for Cu2+ concentration in the electrolyte and 20s for electrodeposition time were the largest photoelectric response and the smallest resistance value of electrochemical reaction of electrode in the light. So the optimal reaction conditions were as follows: 20s for electrodeposition time, 0.4mol/L for Cu2+ concentration in the electrolyte. Then the degradation of rhodamine B was employed as the model reaction to evaluate the photoeletrocatalytic activity of Cu2O modified TiO₂ nanotube arrays.The results of photoelectrocatalysis experiments indicate that the degradation of rhodamine B over metal modified TiO₂ nanotube arrays shows a evident rise compared with TiO₂ nanotube arrays, where exists a certain synergetic effect.更多还原