TiO2纳米管阵列电合成的扩散-反应耦合强化机制研究  

Study on diffusion-reaction coupled strengthening mechanism based on electrosynthesis of titanium dioxide nanotube array

作　　者：周黄 常禹 范兴[1] 张楠楠 陶长元[1] ZHOU Huang;CHANG Yu;FAN Xing;ZHANG Nannan;TAO Changyuan(School of Chemistry and Chemical Engineering,Chongqing University,Chongqing 401331,China)

机构地区：[1]重庆大学化学化工学院,重庆401331

出　　处：《化工学报》2020年第10期4663-4673,共11页CIESC Journal

基　　金：国家自然科学基金项目(21905034,21676033);教育部霍英东基金项目(161067)。

摘　　要：研究针对TiO2纳米管材料批量电合成过程的结构有序性耗失问题,考察了TiO2纳米管阵列生长过程中的非线性动力学机制,及其随电解时间等的演变机制。结合扫描电镜(SEM)及电化学分析表明,TiO2纳米管阵列形成是低聚羟基钛中间体扩散-反应耦合过程中的自组织行为。研究建立了电合成体系的反应-扩散动力学方程组,并对其进行了线性稳定性分析,阐释了TiO2纳米管阵列有序结构形成,乃至出现周期性电化学振荡的参数阈值空间,在此基础上提出了TiO2纳米管阵列电合成过程的扩散-反应耦合强化机制。研究提出的非线性动力学机制广泛存在于各种金属的电溶过程中,并对产物结构及过程电耗有深刻影响。这也为新型纳米材料的批量电合成过程强化提供了理论依据。As an excellent semiconductor material,the TiO2 is widely used in the areas of photocatalysis,solar cells,and biomedical devices.Various technologies have been established to prepare TiO2 nanotube array.These technologies mainly include numerous hydrothermal methods,template method,sol-gel method,and anodic oxidation method.Among them,the anodic oxidation method attracts much attention because of its highly ordered,uniform distribution and variable structure control.At present,the modified preparation of TiO2 nanotube array is still studied by researchers.However,basic study on the kinetic mechanism of the growth process of nanotube array is rare.Herein,we proposed the diffusion-reaction coupled strengthening mechanism based on the electrosynthesis of titanium dioxide nanotube array.Furthermore,the evolution of TiO2 nanotube array with electrolysis time was investigated,and the nonlinear dynamic mechanism of TiO2 nanotube array structure growth process was discussed in combination with SEM and electrochemical impedance analysis.It was found that the formation of TiO2 nanotube array was a self-organization behavior in the diffusion-reaction coupling process of oligomer hydroxyl titanium intermediates.Moreover,the reaction kinetics mechanism was established by analyzing the electrochemical growth mechanism,and its linear stability was analyzed.Besides,the parameter threshold space formed by the ordered structure in TiO2 nanotube array and the accompanying electrochemical oscillation were explained,and its evolution process was also discussed.After optimization,TiO2 nanotube array with ordered structure was prepared.It revealed the internal mechanism of diffusion-reaction coupling in the electrosynthesis of TiO2 nanotube array.In addition,the nonlinear dynamic mechanism proposed in this paper exists widely in the electrodissolution process of various metals,which has a significant influence on the structure formation of products and the power consumption of reaction process.This also provides a theoretical basis for

关 键 词：TIO2纳米管阵列 纳米结构 非线性动力学 化学反应 电化学振荡 线性稳定性分析 

分 类 号：TQ134.1[化学工程—无机化工]