表面等离子共振（SPR）效应提高和拓宽钙钛矿太阳能电池量子效率及机理研究

One of the key issues hindering the further enhancement of power conversion efficiency (PCE) of organ-inorganic perovskite solar cell is its low value (<90%) and narrow spectral response range (300-780 nm) of quantum efficiency (QE) with in the perovskite layer intrinsic optical absorption range. In this Project, we proposed to use the optical couplings between the surface plasmon resonance (SPR) of metallic nanostructures and solar irradiation or photocarriers of perovskite cell to improve the PCE. First, after a theoretical simulation and designing, we will synthesize metal nanostructures including Au, Ag, and Au/Ag heterostructure with different sizes and shapes to achieve highly tunable SPR peaks, which will cover the wide range from 300 nm to 1100 nm. With the far-field scattering mechanism and near-field enhancement feature of metal particle’s SPR effect, the solar cell QE value within the whole perovskite film absorption spectral range will be improved by increasing the light trapping ability. With SPR in the near IR region (780-1100nm) of Au/Ag heterostructure with big length/diameter ratio, the mechanism of broadening the corresponding range of QE spectrum with photon energy lower than the bandgap of perovskite by plasma induced resonance electron tunneling (PIRET) will be investigated with fs-transient absorption (TAS) spectrum. The project is expected to thoroughly clarify the physical mechanism that can overcome the S-Q efficiency limit of solar cell through light-trapping and/or PIRET of SPR effect. Finally, the relationship between the PCE enhancement of perovskite solar cell and the SPR effect of Au/Ag nanostructures will be eventually revealed providing theoretical guidance and material foundation for the development of high efficient perovskite solar cells.

甲胺铅典钙钛矿电池本征吸收范围内量子效率较低（QE<90%），且光谱响应范围较窄（<780nm），是制约进一步提升电池效率的关键瓶颈之一。本项目拟借助金属颗粒表面等离子共振（SPR）效应与入射光生载流子的耦合作用，提高和拓宽钙钛矿电池的QE，进而提高其效率。首先设计并可控合成SPR峰位可调（300-1100nm）的Au、Ag及其异质纳米结构；利用SPR的光捕获机制（包括远场散射和近场增强），提高钙钛矿材料光吸收能力，进而提升电池本征区域QE值；利用大长径比异质纳米结构近红外区域（780-1000nm）的SPR效应，借助飞秒超快光谱技术，探讨通过等离子体诱导共振遂穿（PIRET）拓宽QE光谱响应范围机理。该项目有望彻底澄清SPR效应的光捕获与PIRET在突破太阳能电池S-Q效率极限方面的物理机制，最终揭示SPR与钙钛矿电池QE之间的内在联系，为发展高效钙钛矿电池提供理论指导和材料基础。

本项目针对有机无机杂化钙钛矿和纯无机钙钛矿晶体及薄膜两类典型半导体材料，利用经典的半导体掺杂理论，阐释了施主、受主掺杂对其光电物理性质的影响；针对无机钙钛矿量子点的发光特性，着重讨论了其尺寸依赖效应及量子尺寸效应。利用表面钝化及界面应力外延工程，实现了结构稳定的有机无机杂化钙钛矿和纯无机钙钛矿薄膜制备，为光电器件应用打下了基础。利用典型金属纳米颗粒的SPR效应，将纯MAPbI3有机无机杂化钙钛矿电池效率提升至19%以上，最高填充因子超过83%。本项目突破了钙钛矿半导体材料掺杂和结构稳定性难题，为各类光电探测器件的应用提供了关键基础验材料。..在项目执行期间，累计发表SCI论文25篇，获授权专利2项，获得厅级科学技术奖励1项，培养硕士研究生7人，博士研究生3人。