Development of the mapping method for surface optical constants and its application to in-situ observation of surface photoinduced reaction.

本研究项目的目的是，通过理论和实验方法，在光催化剂薄膜的表面光学常数的高分辨率光学外差显微映射的发展。1）光外差显微测绘系统的基础研究为了建立基于光外差法的表面光学常数的显微测绘系统，建立了基于声光调制器的探测激光扫描系统和光拍频信号检测电路，并研究了它们的基本特性。2）薄膜TiO_2光催化剂表面过程的原位观察采用全息光栅法研究了在紫外光干扰下TiO_2薄膜光催化剂的光诱导表面过程。 ...更多信息 照明。有人建议，反应物和/或反应中间体的微观分布后，可以探测在相应的空间调制的表面折射率。根据实验结果，提出了估算表面过程动力学和表面传质系数等特征参数的建议。3）铁电极上非线性电化学反应的时空传播研究了铁电极上的非线性电化学振荡现象。测量了随时间变化的电位在电解质溶液中的传播和铁电极上时空斑图的形成。关于反应方案，当电阻串联插入在恒电位仪和铁电极之间时，氧化物还原的时空图案以及电流振荡的脉冲形状发生变化。少

The present research project was aimed, by both theoretical and experimental approaches, at the development of a high resolution optical heterodyne micromapping of the surface optical constants at the photocatalyst thin films. Those major issues studied and the results obtained are as follows :1) Basic study for the development of the optical heterodyne micromapping system.In order to establish a micromapping of the surface optical constants based on the optical heterodyne method, a scanning system of a probe laser beam using an AO modulator and the electronics detecting the optical beat signal were setupped and their fundamental characteristics were studied. The results were compared with those obtained by the holographic method described below.2) In situ observation of the surface processes at thin-film TiO2 photocatalystHolographic grating method was undertaken in order to study the photoinduced surface processes as modeled at a TiO2 thin-film photocatalyst under the interfering uv- … More illumination. It was suggested that the microscopic distribution of reactants and/or reaction intermediates upon photocatalysis can be probed in terms of the corresponding spacial modulation of the surface refractive index. Based on the experimental results those characteristic parameters for the surface processes such as kinetics and the surface mass transfer coefficient were suggested to be estimated.3) Spatiotemporal propagation of non-linear electrochemical Reaction over iron electrodeNon-linear electrochemical oscillation of iron electrode was studied in terms of the test surface reaction accompanying the change in surface optical constants. The time dependent potential propagation into an electrolyte solution and spatiotemporal pattern formation on iron electrode were measured. Concerning the reaction scheme, when the resistance was inserted in series between the potentiostat and the iron electrode, the spatiotemporal pattern of the oxide reduction varied as well as the pulse shape of the current oscillation. Less