基于ZnO纳米棒/石墨烯异质结构的钙钛矿量子点共敏化太阳能电池研究

Solar energy is a clean, safe, renewable green energy. In order to absorb and utilize sunlight effectively, perovskites (CH3NH3PbI3-xClx) and quantum dots (PbS) heterocrystals co-sensitized ZnO nanorods/graphene heterostructure solar cells were assembled in this project, and the principle and character of the perovskites solar cells were investigated. The project will study on the composition, structure and growth mechanism of CH3NH3PbI3-xClx and PbS heterocrystals. And study on the photoelectric performance of perovskites and quantum dots co-sensitized ZnO nanorods/graphene heterostructure solar cells. Discussion on the components, energy transfer, photovoltaic conversion mechanism of the perovskites and quantum dots co-sensitized ZnO nanorods/graphene perovskites solar cells. The electronic transport properties of perovskites and the optical absorption properties of quantum dots are combined together to broaden the absorption range of the solar light，and the ZnO nanorods and graphene are combined to form heterostructure materials, which can improve the photoelectric performance of this perovskites solar cell effectively. The investigated on these key scientific issues could provide theoretical and experimental basis for the potential low cost, long life and high efficiency solar cells.

太阳能是一种清洁安全的可再生绿色能源，本项目将钙钛矿CH3NH3PbI3-xClx与PbS量子点相结合生成异质结晶材料，研究CH3NH3PbI3-xClx和PbS异质结晶材料的组成、结构及生长机理；研究不同组成和配比CH3NH3PbI3-xClx、PbS共敏化对ZnO纳米棒/石墨烯钙钛矿太阳能电池光电性能的影响，探讨钙钛矿太阳能电池的组成、能量传递、光电子产生、分离及传输等光电导性能以及光电转换机理。项目将钙钛矿优异的电子传输性能和量子点的光吸收性能有效结合，以拓宽对太阳光的吸收范围；并将ZnO纳米棒和石墨烯结合生成异质结构材料，以提高CH3NH3PbI3-xClx、PbS共敏化ZnO纳米棒/石墨烯异质结构钙钛矿太阳能电池的光电性能，可以为潜在的低成本、长寿命、高效太阳能电池的应用开发提供理论和实验基础。

当前，研究开发绿色清洁、环境友好的可再生新能源已成为热门的研究领域，太阳能是一种可再生的清洁能源，具有储备丰富、安全清洁等显著优点。本项目设计合成了PbS、CdSe@CdS等量子点材料；CH3NH3PbI3(MAPI)、CsPbBr3等钙钛矿材料，并基于PbS量子点与MAPI钙钛矿材料的结构、能级匹配等性能，设计合成了PbS-MAPI量子点/钙钛矿异质结晶材料。研究表明：与CdS量子点相比，经CdSe@CdS核壳型量子点敏化的ZnO纳米棒光阳极的紫外可见光吸收可从470nm红移到540nm；当PbS量子点沉积在TiO2纳米管后，其吸收范围可拓宽至710nm，当MAPI沉积到TiO2纳米管上时，其吸收范围可拓宽至795nm，PbS-MAPI异质结晶敏化的TiO2纳米管光阳极的吸收范围显示出了更宽的光谱响应范围（200-815nm），有效拓展了光谱吸收范围。以量子点、钙钛矿和量子点/钙钛矿异质结晶材料敏化ZnO纳米棒、ZnO纳米棒/石墨烯、TiO2纳米棒/管等材料作为光阳极，以Pt、碳浆、Cu2S等作为对电极，组装钙钛矿太阳能电池。研究表明：ZnO/CdSe@CdS光阳极材料组装的太阳能电池的光电转换效率为1.21%，分别是CdS、CdSe单独敏化ZnO和未敏化ZnO纳米棒光阳极组装的太阳能电池的2、2和4倍；经溶剂工程法处理后的MAPbI3薄膜致密度提升，MAPbI3敏化ZnO基钙钛矿太阳能电池光电转换效率为6.20%，相比于未经处理的MAPbI3敏化ZnO基钙钛矿太阳能电池（4.20%），其效率提升了1.5倍。PbS-MAPI异质结晶敏化TiO2纳米管光阳极组装得到的太阳能电池的光电转换效率增至5.98%，分别是未敏化TiO2纳米管、PbS量子点、MAPI单敏化TiO2纳米管太阳能电池的光电转换效率的46、4.12和2.96倍。项目研究为潜在的高效太阳能电池的应用开发提供了理论和实验基础。