基于确定性非周期金属微纳结构的宽光谱调控有机太阳能电池研究

Organic solar cells (OSCs) hold great potential in portable intelligent electronics and solar curtain due to their desirable features such as lightweight, flexibility and solution-processability. However, their practical applications have been hindered by the low power conversion efficiency, which is mainly attributed to the inefficient light harvesting of the solar spectrum. Although the use of the conventional periodic patterns or metal nanoparticles can, to some extent, enhance the light harvesting efficiency, the light manipulation is rather dependent on the special wavelength. It is therefore highly desirable to explore the broadband light manipulation structures for the sufficient absorption of solar radiations. In this project, we propose to develop the novel deterministic aperiodic metal nanostructures to achieve efficient and broadband light manipulation. The influence of the designed nanostructures on device performance and photoelectric conversion process will be systematically investigated. The integration strategy of nanostructures and devices will be developed. Finally, highly efficient single-junction OSCs will be constructed to achieve the power conversion efficiency over 17%, which will promote the development of OSCs for the practical applications.

有机太阳能电池以其轻质、柔性、可印刷制备等独特优势在便携电子设备、太阳能幕墙等方面具有广泛应用前景。但其发展受制于较低的能量转换效率，其中一个重要因素是器件不能实现太阳光的高效俘获。使用传统的周期性微纳结构或金属纳米颗粒可以一定程度上增强有机太阳能电池的光俘获，但其光调控波长的选择性限制了光谱调控范围。因此，迫切需要开发具有宽光谱调制能力的微纳结构，实现太阳光的高效俘获。本项目将以新型确定性非周期金属微纳结构的设计为切入点，探索光调控结构设计新策略，解析微纳结构与器件光电转换性能的构效关系，发展微纳结构与器件的集成工艺，实现太阳光的宽光谱高效俘获，获得高效率的有机太阳能电池，争取单结电池效率超过17%，为有机太阳能电池的实际应用提供技术支撑。

近年来，尽管窄带隙非富勒烯受体材料的迅猛发展使有机太阳能电池的效率获得持续突破，但是半导体材料的载流子迁移率仍然较差，限制了光活性层的厚度，进而使有机太阳能电池的光伏获效率仍待提升。特别是，基于窄带隙非富勒烯活性层体系在蓝光区域（400-500 nm）的光俘获能力较差，有机太阳能电池在该波段的外量子效率通常只有50%-60%。基于此，本项目提出基于金属图案的宽光谱响应光学调控新策略，揭示了微纳金属结构的微观形成机制及其对器件光吸收和能量转换过程的调控机理；同时，发展柔性透明电极的可控制备工艺，结合微纳结构抑制透明金属电极光损耗，阐明了表面等离子激元能量转移调控与器件光电转换性能的构效关系；结合高性能活性层体系，制备了基于新型图案化金属电极的有机太阳能电池，增强了器件在300-1000 nm光谱范围内的光响应，获得最高器件吸收率达到95%，实现柔性和刚性器件的效率均突破18%。