阵列化半导体量子点的制备及其在太阳电池中的应用

项目名称： 阵列化半导体量子点的制备及其在太阳电池中的应用

项目编号： No.60806045

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 崔灿

作者单位： 浙江理工大学

项目金额： 20万元

中文摘要： 本课题主要是通过优化量子点和太阳电池结构探索制备高性能太阳电池的途径，得到如下主要结果：(1) 使用无注入的化学合成法制备了能带可调的CdS1-xSex量子点，通过吸附不同成分的CdS1-xSex量子点调节TiO2光电极的光谱响应范围，并发现TiO2光催化降解TiO2/CdS1-xSex界面的油酸，提高了光生载流子的分离效率，使得光电极的量子效率在光照的初始阶段逐渐增大。（2）制备了TiO2/CdSe多层膜太阳电池光电极，电化学法沉积的CdSe薄膜沿着（111）方向择优生长，光吸收强度随着薄膜沉积层数的增加而增强，在二层膜体系中开路电压和短路电流密度最大，光电化学性能最好。（3）制备了CdS或者CdSe敏化的TiO2纳米棒阵列和ZnO纳米棒阵列太阳电池，分析了微结构对电池效率的影响，并发现CdS/CdSe共敏化可以提高光电极的吸收效率，增强光电流。（4）制备了两种结构新颖的TiO2/CdS双层空心球结构，研究了它们的光学性质、微结构和可见光光催化性质。（5）研究了不同热处理条件对氧化硅薄膜中硅量子点形成的影响，发现二步低高热处理有利于硅团簇的形核，能提高硅量子点的密度和均匀性。

中文关键词： 半导体；量子点；太阳电池

英文摘要： Though the investigation of high quality quantum dots (QDs) and solar cell structure, methods of constructuring high efficient solar cells have been explored and primary conclusions listed below have been obtained. (1)Band-gap tunable CdS1-xSex colloidal QDs synthesized with a novel non-injection method were used to sensitize TiO2 electrode, and it was found that the deposition of CdS1-xCdSex with different composition could modify the optical obsorption region of electrodes. Furthermore, the TiO2 could degradate oleic acid under light illumination and hence enhance the separation of photon-excited electrons and holes. As a result, the solar cell efficiency inceased during the light irradiation at the early stage of illumination.(2)Multilayer TiO2/CdSe photoelectrodes were constructed by depositing CdSe on porous TiO2 thin film. It was found that the CdSe thin film grew preferentially along the (111) direction and the optical obsorbance increased with the increasing of layer number of TiO2/CdSe. The optimal photoelectrochemical current and open-circuit voltage were obtained in a biolayer TiO2/CdSe system.(3)CdS or CdSe sensitized TiO2 nanorod array (or ZnO nanorod array) solar cells have been fabricated and the effect of the microstructure on the efficiency have been studied. The results showed that the co-sensitization of CdS/CdSe could enhance optical obsorbance and hence enhance the photoelectrochemical current.(4)Two novel double-shelled TiO2/CdS hollow spheres have been synthesized and their optical properties, microstructure and visible-light photocatalytic activity have been studied.(5) The effect of the subsequent annealing on the formation of Si QDs embeded in SiO2 matrix has been studied, and it was found that the two-step low-high thermal treatment could facilitated the nucleation of silicon clusters and hence improve the density and uniformity of Si QDs in the SiO2 thin film.

英文关键词： semiconductor;quantum dots; solar cells