量子点和稀土离子共敏化二氧化钛纳米管阵列太阳能电池的研究

Now, solar energy was a new type of clean and renewable energy. In order to absorb and utilize sunlight effectively, quantum dots and rare earth ions combine in this project, and the principle and character of quantum dots and rare earth ions co- sensitized TiO2 solar cell were investigated. The project will study on the effects of anodization parameters of electro chemical anodic oxidation on the TiO2 nanotube morphology and length. And study on the structure and photovoltaic behavior of quantum dots sensitized solar cells, which using CdTe, Cd1-xZnxTe to sensitize TiO2 nanotube arrays layer. And also study on the co- sensitized process on quantum dots sensitized TiO2 nanotube arrays, which using the Eu3+, Sm3+, Er 3+ and Yb3+-doped rare earth oxides as co-sensitizer. According to quantum dots and rare earth ions doped oxides materials in the visible and near infrared absorption characteristics, design and optimize the structure of TiO2 nanotube solar cells. And control of the absorption spectra to improve the photovoltaic behavior of the quantum dots and rare earth ions co- sensitized TiO2 nanotube solar cell. The investigated on these key scientific issues is great significance not only for the quantum dots and rare earth ions co- sensitized TiO2 nanotube solar cell structure and performance optimization, but also for the solution to the low efficiency problem of the quantum dots sensitized TiO2 nanotube solar cell.

太阳能是一种新型的可再生清洁能源，本项目将量子点和稀土离子相结合，研究能对太阳光进行有效吸收利用的量子点和稀土离子共敏化TiO2太阳能电池的原理及性质。研究通过控制电化学阳极氧化法制备条件对纳米管阵列的长度和形貌进行有效调控的实现途径；研究CdTe、Cd1-xZnxTe量子点敏化对TiO2纳米管结构和光电性能的影响；研究以Eu3+，Sm3+，Er 3+和Yb3+等离子作为激活剂的稀土氧化物纳米荧光材料对量子点敏化TiO2纳米管太阳能电池的共敏化作用。根据量子点和稀土离子掺杂纳米荧光材料在可见光区和近红外区的吸收特性，设计和优化TiO2纳米管太阳能电池的结构，实现对其吸收光谱的有效调控，提高量子点和稀土离子共敏化TiO2纳米管太阳能电池的光电性能。本项目的成功实施将为进一步推进TiO2材料的设计奠定良好的基础，对解决量子点敏化TiO2纳米管太阳能电池光电转换效率低的难题具有重要的实际意义。

本项目通过一步水相法合成了单一型CdSe、CdTe量子点、掺杂型CdSe:Eu2+、ZnSe:Mn2+、ZnS:Mn2+、CdTe:Ce3+量子点、合金型CdSexTe1-x、ZnxCd1-xSe和核壳型CdSe/CdS、CdTeSe/ZnS、ZnCdTe/CdSe量子点，所制备的量子点的发射波长覆盖范围可以从可见光到近红外区，荧光量子产率最高值为52.1%。.探讨了稀土离子掺杂荧光材料的制备条件和发光性质。分别通过溶胶-凝胶法、固相法合成了BaM2ZnO5:Eu3+ (M = La, Gd)、Sr6Ca4(PO4)6F2: Eu2+等单掺杂荧光材料；NaCaPO4: Tb3+, Eu3+、LiMgBO3:Eu3+, Bi3+、Li6Gd(BO3)3:Ce3+, Tb3+等双掺杂荧光材料，Li6Gd(BO3)3: Tb3+/Bi3+, Eu3+、Ba2Y(BO3)2Cl: Ce3+, Tb3+, Eu3+、Y2SiO5: Ce3+, Tb3+, Eu3+等三掺杂荧光材料，通过调节激活剂与敏化剂间的比例和能量传递，实现单相荧光材料多色发光的连续可调，并且通过Ce3+→Tb3+→Eu3+能量级联传递，制备了在近紫外及紫外区有宽带吸收、颜色可调、可以覆盖整个可见光波长范围的荧光材料。.分别以CdS和CdS:Eu3+量子点敏化TiO2纳米管作为光阳极组装太阳能电池，CdS:Eu3+量子点敏化TiO2纳米管太阳能电池的量子效率在波长为300-480nm范围内最高可达21%。其最高光电转化效率为0.39%，分别是未敏化的TiO2纳米管和CdS量子点敏化TiO2纳米管太阳能电池的2倍和1.6倍；合成了掺铕碱土金属锆酸盐荧光粉AZrO3:Eu3+（A = Ca，Sr，Ba）与TiO2纳米管的复合材料，与没有复合红色荧光粉的TiO2纳米管相比，所合成的复合材料在400-650 nm可见光区的吸收明显增强。以CdS量子点敏化ZnO纳米棒作为光阳极组装太阳能电池，以TiO2/PbS纳米管复合材料作为对电极时，当PbS量子点敏化TiO2纳米管6个周期时得到的复合对电极太阳能电池的光电转换效率是TiO2对电极太阳能电池的2.28倍，是Pt对电极太阳能电池的4.41倍。并且研究了通过直接吸附法、连续离子层吸附反应法、一步合成法等量子点和稀土离子敏化 TiO2纳米管和ZnO纳米棒的方法。