具有高效等离子体效应的Au@Ag纳米棒的可控制备及其光伏增强效应研究

It is of great importance to promote the power conversion efficiency of a solar cell for converting solar energy into electricity more efficiently. Due to the localized surface plasmons (LSP) resonance, the Au and Ag nanoparticles demonstrate themselves as one of the most important approaches to promote the light harvesting efficiency (LHE) and improve the efficiency of the solar cells. However, constructing of plasma incorporated and LHE enhanced perovskite solar cells (PSCs) is still a big challenge, owing to the limitation of the optical nature of the conventional plasmonic particles with simple spherical structure. In this project, novel plasmonic Au@Ag core-shell nanorods with wideband, strong and adjustable absorbance are proposed to enhance the sunlight, especially the part with low energy, harvesting efficiency and improve the PSCs efficiency remarkably. Efforts will be devoted to carefully studying the fabrication conditions, the microstructures, the optic properties and the simulated LSP effects of the obtained Au@Ag materials. Thus, the interaction law and the some theoretical principles regarding to the relationship between the fabrication, structure and properties will be established and employed, in return, to direct the fabrication of Au@Ag core-shell nanorods with desired performance. Meanwhile, various architectures of Au@Ag incorporated devices will be investigated both experimentally and theoretically to study how the Au@Ag affects the light-absorption behavior of the perovskite photoanode and power conversion efficiency of the PSCs devices. The working principle and mechanism of the plasmonic materials in the PSCs devices will thus be clarified and a technical route for constructing plasma enhanced PSCs will also be concluded. The achievement of the proposed project is of significance to provide new ideas and guidance of synthesizing excellent plasma materials and their enhancement effects in photovoltaic.

提高太阳能电池光电转化效率是高效利用太阳能的必然要求，利用Au、Ag的等离子体效应（LSP）是提高太阳能电池光电转化效率的有效方法。然而，高效光吸收增强型钙钛矿太阳能电池（PSCs）的开发一直受传统结构等离子体光学特性的限制。本项目拟开发强吸收、LSP响应波长可调的Au@Ag核壳结构纳米棒，解决传统结构等离子体材料吸光特性与钙钛矿吸收光谱不匹配的难题，实现PSCs对入射光的强化利用，大幅度提高PSCs的效率。通过结构表征与理论模拟，揭示Au@Ag制备条件-结构-性能间的作用规律和相关理论，实现具有设定光学特性的Au@Ag的可控制备；通过电极结构设计和理论计算，深入揭示等离子体粒子在PSCs中的作用机制和机理，提出利用等离子体光调控法构建高性能PSCs的技术原理。本项目的实施将为高效等离子体纳米材料的构效关系研究及其光伏增强效应奠定一定的理论基础，对其它光响应器件的开发具有参考价值。

提高太阳能电池光电转化效率是太阳能光伏高效利用的前提，而强化对入射光的利用是提高太阳能电池效率的关键。利用Au、Ag的等离子体效应（LSP）是提高太阳能电池光电转化效率的有效方法。然而，高效光吸收增强型钙钛矿太阳能电池（PSCs）的开发受传统结构等离子体的光学特性的限制。本项目围绕等离子体材料的设计、制备、光学性能调控及其在增强太阳能电池光伏效率中的应用展开。项目的开展成功合成并揭示了Au@Ag等离子体离子的微观结构（Au纳米棒核的长径比、Ag层厚度、Au@Ag的长径比）与其光学性能的构效关系，实现了等离子体材料的消光峰在可见-近红外区间的连续可调；阐明了等离子体粒子消光光谱与太阳能电池本身吸收光谱互补匹配的基本原则，提出了通过电池结构设计来充分利用等离子体材料的LSPR 近场及远场效应实现太阳能电池光谱调控的策略。通过实验结果结合理论计算，明确了等离子体增强光伏的相关机制。所制备的等离子体增强超薄吸光层钙钛矿太阳能电池和染料敏化太阳能电池分别获得了18.3%和10.58%的光电转化效率。所设计的太阳能电池应用前景在于：（1）制备高效率半透明钙钛矿/染料敏化太阳能电池，进而与硅太阳能电池等其它光伏技术叠层，进一步提高太阳能的利用率；（2）在确保太阳能电池高效率的前提下，等离子体材料光伏增强效果可大幅度降低含铅钙钛矿光吸收层厚度，实现“物理降铅”，推动钙钛矿光伏技术的实用化进程。项目的完成推动高性能Au、Au@Ag等离子体粒子合成技术及等离子体增强光伏技术的进步，为实现高效吸收全色入射光的太阳能电池的设计和制备提供新思路和科学依据，为其它光化学、光电化学技术研究提供了参考依据，具备较好的创新性和较为重要的科学意义。