基于氧化物纳米线三维异质结结构的钙钛矿量子点太阳能电池研究

In this proposal, we plan to construct high efficiency and stability 3 dimensional heterojunction solar cells by combining n-type oxide nanowire arrays electron transfer layer, a-CsPbI3 perovskite quantum dot photo absortion material and p-type spiro-OMeTAD hole transfer layer. To solve the key scientific problem of the conflict between photo absortion and carrier separation in quantum dot solar cells, relevant issues will be investigated including materials growth, structure engineering, interfacial defects passivation and device mechanism analysis. The size, crystalline phase, band gap and stability can be controlled effectively by modify the preparation process of n-type oxide nanowire arrays and perovskite quantum dot. The 3D heterojunction solar cell will be established in order to balance the absorptivity and the carrier diffusion and elucidate the mechanism of charge separation, recombination and transportation. The harvest efficiency and stability of solar cells can be greatly enhanced by the interface engineering which could clarify mechanism of charge recombination and energy band structure. This project will provide an effective method for 3D heterojunction quantum dot perovskite in solar cells, which can provide scientific evidences and technical bases for thin film solar cells.

本课题的研究目标是利用n-型氧化物纳米线电子传输材料、a-CsPbI3量子点光吸收材料和spiro-OMeTAD空穴传输层构建高效、高稳定性的三维异质结钙钛矿量子点太阳能电池，拟解决量子点太阳能电池中光吸收和载流子分离之间矛盾的问题，开展相关的材料生长、结构设计、界面处理和器件机理分析等研究工作。通过对n-型氧化物纳米线及钙钛矿量子点的可控制备，实现对材料尺寸、晶相、带隙及稳定性的有效控制；通过构建三维异质结太阳能电池器件，探寻增加光吸收率的同时又能够有利于载流子扩散的有效途径，揭示器件中光生电荷的分离、复合和输运机理；通过界面工程，深入理解界面复合机制和能带结构，进一步提高器件光电转换效率和稳定性。在此基础上，总结三维异质结钙钛矿量子点太阳能电池制备方案，为实现制备高效、稳定钙钛矿太阳能电池奠定基础。

本研究提出用n型宽带隙氧化物纳米线阵列与胶体钙钛矿量子点构造高性能三维异质结钙钛矿量子点太阳能电池器件。项目将围绕三维异质结钙钛矿量子点器件中的材料制备和表征、异质结界面工程和器件优化三个主要方向。探索三维异质结太阳能电池的制备方法，包括获得稳定的钙钛矿量子点材料；调控纳米线电子传输层微纳结构；研究降低界面缺陷的界面工程；阐明器件工作的物理机制。研究钙钛矿量子点和纳米线阵列的三维异质结构型，通过三维结构增加量子点负载保证光吸收率，利用载流子扩散与光吸收方向的正交关系保障载流子的有效输运。进一步研究降低界面缺陷密度的界面工程，提高光生载流子的分离效率，减小复合，揭示界面工程的优化结构设计及缺陷钝化机理。制备高性能钙钛矿量子点太阳能电池器件为未来能源领域提供了新的材料和器件结构体系。