A Photoelectrochemical Investigation of Zirconium oxide film

用光电化学方法研究了金属锆的表面初始氧化膜和线性电势扫描形成阳极氧化膜．光电流作用谱上的阳极和阴极光电流取决于电极电势，而与成膜和测量溶液基本无关．光电流作用谱和瞬态光电流响应说明锆表面氧化膜为双层结构，内层为ＺｒＯ＿２外层为ＺｒＯ＿２·（Ｈ＿２Ｏ）＿ｎ．光电流可以来自内、外层的光生载流子和基底金属的内光注入电子迁移至电极／溶液界面与溶液中的氧化还原对反应，光电流作用谱的分析给出了三个过程的光学间能值，分别为４．５ｅＶ、３．０ｅＶ和２．０ｅＶ．A photoelectrochemical investigation has been carried out on zirconium initialoxide film and its oxide film grownanodically at constant rate up to different thickness. Both anodicand cathedic photocurrents on the photocurrent spectrum depended on the potential,but had littlerelation with the forming anedic films or measuring solutions. Photocurrent spectrum and photocurrenttransients suggested that the oxide films on zirconium were duplex layers structure. The internal layerwas ZrO_2 and the external layer ZrO_2·(H_2O)_n. The photocurrent included photogenerated carrier ininternal and external oxide films,as well as internal photoinjection process for electrons from thesubstrate metal into the electrode/electolyte interface reacting with the redox couple. The analysis ofphotocurrent spectra has given the threshold energies for three processes.作者联系地址：北京大学化学系，广西民族学院化学系Author's Address: Department of Chemistry, Beijing University, Beijing,100871Di Quarto F. Piazza S. Sunseri C. Dipartimento di Ingegneria Chimica dei Processi e dei Materiali,Universita di Palermo, Viale delle Scienze, 90128 Patermo,ItatyWei PingDeparteme

Laser Scanning Miero-area Photovoltage Imaging of Corrosion on the SurFace of Copper

铜表面腐蚀的激光扫描微区光电压图象的研究杨迈之，张雯，蔡生民，任聚杰（北京大学化学系，北京，100071）（河北医学院化学系，石家庄）潘传智，杨勇（浙江工业大学化工系，杭州）（厦门大学化学系，厦门）关键词铜，缓蚀剂，微区光电压图铜的腐蚀与防腐早已引起...The laser scanning micro-area photovoltage technique has been used in the research of copper corrosion in 3% NaCl solution.With the result of this method, the procedure of the local corrosion can be deseribed, and the eFFect of the corrosion inhibitor can also be evaluated.国家自然科学基金;青年基金;国家教育委员会优秀年轻教师基金;厦门大学固体表面物理化学国家重点实验室基

LASER-SCANNING MICROAREA PHOTOVOLTAGE IMAGING OF CORROSION ON THE SURFACE OF COPPER

The laser scanning micro-area photovoltage technique has been used in the research of copper corrosion in 3%NaCl solution. With the result of this method, the procedure of the local corrosion can be described, and the effect of the corrosion inhibitor can also be evaluated

Photoelectrochemical and Spectroelectrochemical Studies onIron Oxide Ultrafine Particles

用拉曼光谱、光电流、紫外－可见反射谱等技术研究了附着在铂片表面的α－Ｆｅ＿２Ｏ＿３微粒．拉曼光谱的蓝移现象说明５０ｎｍ粒径的粒子较块体材料有尺寸量子化效应．随着电极电势的变化，光电流增加时，ＵＶ－ＶＩＳ反射率相对变化量减少；光电流减少，ＵＶ－ＶＩＳ反射率相对变化量则增大，说明电极电势不仅影响溶液氧化－还原对的氧化还原趋势，而且还影响微粒表面的光吸收．in this paper, Raman spectra, photocurrent and the UV-VIS reflectance aremeasured for studying the α-Fe_2O_3ultrafine particles adsorbed on Pt electrode. The blue shifts ofRaman peaks demonstrate the size quantization effect for the particles of 50 nm in diameter ascompared with the bulk material. With the changing of the potential , the photocurrent decrcases as theUV-VIS reflectance increases, and vice-versa. Therefore, the potential not only affects the hargetransfer direcdtion in the interface of electrede/redox couple, but also influences the light absortion onthe surface of particles.According to the results of photoelectrochemistry, we suggest that the cathedicphotocurrent in the potential range of more than negative 270 mV arises from a reduction process ofthe photo-induced oxidation product on the platinum substrate electrixle and the anodic one in the rangeof more than positive 270 mV, and arises from a directly photo-induced oxidation process on thesurface of partiles.作者联系地址：北京大学化学系，牡丹江师范学院,厦门大学化学系Author's Address: Dept. of Chem. Bdijing University, Beijing 100871Lu XiaojiangDept. of Chem. Mudanjiang Teacher's College., Mudajang 157000Tian Zhongqun; Luo JinDept. of Chem. Xiamen univ. Xiamen 36100

Photoelectrochemical Studies on Nanoporous TiO 2/PAn film electrode

用光电流作用谱、光电流电势图等光电化学方法研究了ＴｉＯ２／聚苯胺复合多孔膜电极在不含氧化还原对和含有不同氧化还原对体系中的光电转换过程．结果说明，ＴｉＯ２／聚苯胺复合多孔膜电极为双层ｎ－型半导体结构，ＴｉＯ２多孔膜的禁带宽度为３．２ｅＶ，外层聚苯胺膜的禁带宽度为２．８８ｅＶ．用导电高聚物修饰半导体电极可以使可见光区光吸收增强，光电流明显增加，产生光电流起始波长红移至＞６００ｎｍ，从而提高了宽禁带半导体电极的光电转换效率．The photon to electricity conversion process of nanoporous TiO 2/PAn film electrode was studied in electrolytes with and without redox couple by using the photocurrent action spectra and potential dependence of photocurrent. It is concluded that the nanoporous TiO 2/PAn film electrode has a structure of duplex n type semiconductor layers. The band gap of PAn film is 2.88eV.The TiO 2 nanoporous film electrode modified by PAn can extend the range of optical absorption into visible and infrared region and effectively increase the photocurrent in the visible and infrared region. The photocurrent threshold shifts to>600nm and conversion efficiency of light to electricity is improved.作者联系地址：北京大学化学系,中科院化学所有机固体实验室Author's Address: Department of Chemistry, Peking University, Beijing 100871 Li Yongfang Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences,Beijing,1008

Photoelectrochemical Studies on the TiO_2 Nanostructured Porous Film Sensitized by Cyanine Dye

研究了三甲川菁染料敏化ＴｉＯ２ 纳米结构电极的光电化学行为．结果表明，使用该染料敏化可显著提高ＴｉＯ２ 纳米结构电极的光电流，使电极的吸收波长红移至可见光区，光电转换效率得到明显改善，ＩＰＣＥ值最高可达１２－１ ％ ．The photoelectrochemical behaviors of the TiO 2 nanostructured porous film sensitized by cyanine dye were investigated in this paper.The results showed that the excitaed state level matched the conduction band edge of TiO 2 nanoparticle.Therefore the sensitization of the dye can increase the photocurrent intensity of the TiO 2 nanostructured electrode obviously and results in a red-shift of optical absorption from the ultra_violet region to the visible.As a result,the light_to _electricity conversion efficiency was improved evidently,the maximum value of IPCE has reached 12.1%.作者联系地址：北京大学化学与分子工程学院!北京100871,北京大学化学与分子工程学院!北京100871,北京大学化学与分子工程学院!北京100871,北京大学化学与分子工程学院!北京100871,北京大学化学与分子工程学院!北京100871,北京大学化学与分子工程学院!北京100871,华东理工大学精细化工研究所!Author's Address: College of Chenistry and Molecular Engineering,Peking University,Beijing 100871 Meng Fanshum Tian He Institute of Fine Chemicals,East China University of Scienc