基于陷光结构和表界面调控的有机-晶硅太阳能电池光伏性能研究

Systematic research work on low-cost, high-efficiency solar cell has an important scientific significance and practical value to solve the problems of energy shortage and environmental pollution. Considering the high reflectance of organic/crystalline-silicon solar cells based on planar silicon, in this project, light-trapping structures formed on silicon substrate via soft embossing and metal assisted chemical etching method will be used to enhance the absorption of light. However, silicon with light-trapping structures may result in high carrier recombination. To overcome this problem, surface passivation of the obtained light-trapping structures and doped PEDOT:PSS layer will be adopted to promote carrier transport and reduce recombination. Effects of various features of light-trapping structures on the photoelectric conversion efficiency of solar cells will be discussed by comparing the performance of solar cells made with planar silicon and light-trapping structures with different morphologies, sizes, and duty cycles. The effects of light-trapping structures on the absorption and scattering process of photons will be systematically studied; the effects of organic/crystalline-silicon surface/interface engineering on the carrier transport properties will be discussed. The project is expected to reveal the physical origin that affects the photoelectric conversion efficiency of solar cell and find possible ways to improve the performance of solar cell. The findings of this project will provide both the theoretical and experimental basis for the development of low-cost and high-efficiency solar cell. It could also have potential economic and social benefits.

低成本、高效光伏器件研究对解决能源短缺和环境污染具有重要的科学意义和实用价值。针对采用平面硅制备有机-晶硅太阳能电池对光的反射率高的缺点，本课题提出了采用软模板压印结合金属辅助化学刻蚀在硅表面构建陷光结构来提高电池对光的吸收；针对陷光结构引入可能会导致载流子复合加强的问题，本课题提出了通过对陷光结构表面钝化、对PEDOT:PSS进行掺杂，促进载流子输运，减少复合。通过对比研究由平面硅以及表面制备了不同形貌、大小、占空比的陷光结构硅片所制成电池的光电性能探讨陷光结构变化对电池光电转换效率的影响。系统深入研究陷光结构的引入对电池中光子吸收和散射的影响;有机-晶硅表界面调控对载流子输运的影响;进一步揭示影响电池光电转换效率的物理起源，提出提高电池性能的可行方案。本项目的研究结果将为发展低成本、高效太阳能电池提供理论和实验依据，具有潜在的经济效益和社会效益。

低成本、高效光伏器件研究对解决能源短缺和环境污染具有重要的科学意义和实用价值。针对采用平面硅制备有机-晶硅太阳能电池对光的反射率高的缺点，为了增强光吸收提高太阳能电池效率，本课题提出了在硅片表面制备多种陷光结构，主要包括正金字塔结构、倒金字塔结构、有序倒金字塔和正金字塔复合结构等等。然而，带有陷光结构的硅片应用于有机/晶硅太阳能电池可能会导致高载流子复合率。为了解决这一问题，课题组采用氢氟酸/硝酸混合液或四甲基氢氧化铵溶液（TMAH）处理带有微纳结构的硅片。所制备的带有微纳结构的硅片被成功地应用于有机/晶硅太阳能电池。太阳能电池的性能表征结果表明采用有序倒金字塔和正金字塔复合结构的太阳能电池经处理后其光电转换效率有所提高。通过比较平面硅和带有不同形貌陷光结构制备的太阳能电池的效率，讨论了陷光结构对太阳能电池性能的影响。测量了带有不同形貌陷光结构的硅片的反射光谱。结果表明，在硅表面形成微纳结构后，光反射有所减弱。低反射率可归因于在硅片表面制备的微纳结构具有很强的陷光性能。带有陷光结构的有机/晶硅太阳能电池的最高光电转换效率为12.34%。此外，在项目执行期间，考虑到光电极大的表面积和快速电子传输特性对染料敏化太阳能电池效率的提高起着至关重要的作用。课题组设计了一种离心辅助法制备了纳米颗粒修饰的分层纳米线阵列。所制备的微纳结构被成功应用于太阳能电池。当光电极的厚度约为20微米时，能量转换效率可达5.52%。本项目的研究结果为开发低成本、高效率太阳能电池提供了实验依据，具有潜在的经济效益和社会效益。