【作者】 王英楠；

【导师】 邹广田； 李子亨；

【作者基本信息】 吉林大学 ， 凝聚态物理， 2007， 硕士

【摘要】 本文利用固相反应法和水热合成法分别制备出不同粒径的纳米ZnFe₂O₄材料,并且利用表面光电压谱（SPS）和场诱导表面光电压谱（FISPS）进行了测试分析,分析了光激发电子-空穴对的运动状态以及它们对表面光电压带来的各种响应。得到了当ZnFe₂O₄材料尺寸接近或小于它的载流子德布罗意波长时,将会出现光伏响应峰蓝移现象。结合拉曼光谱的分析了尖晶石结构铁酸锌的振动模式,表明了ZnFe₂O₄在光照和外电场的共同作用下,都会使得它的一阶振动模增强,初步认为造成的原因是材料中无序的阳离子Fe³⁺和Zn²⁺占据了八面体和四面体中氧原子位置引起的。更多还原

【Abstract】 ZnFe₂O₄, one of the most important ferrite binary oxides with the spinel structure, has been of great interest for a long time because of its importance in many technological applications. Surface Photovoltage Spectra （SPS） is a sensitive tool for detecting the photogenerated charge at the surface of semiconductor materials. However, SPS is little employed to study ZnFe₂O₄, especially its corresponding nanostructure.Applied external electric field can promote the separation of photogenerated electron-hole pairs, and thus influence the transfer, capture, and recombination of photogenerated carriers. Therefore, field-induced surface photovoltage spectra （FISPS）, which is normally considered as the steady state SPS, can detect the nice change of photogenerated charge at the surface of semiconductor materials. In this thesis, we use SPS and FISPS to obtain the surface photovoltage spectra of ZnFe₂O₄, and study the effects of illumination, sample size, and field on its surface voltage. Well-crystallized ZnFe₂O₄ with ultrafine sizes was prepared by a hydrothermal reaction. When the size of ZnFe₂O₄ sample is less than 10 nm, FISPS allows us to observe its blue-shift phenomena. This blue shift, corresponding to the excition transition, occurs in the presence of an electric field. With the effect of both field and illumination, all the five first-order Raman active modes increase, which is attributed to the existence of non-order Fe3 and Zn2+ in the structure of octahedron and tetrahedral of samples,and their sites are changed with Oxygen.更多还原