The effect of 2-D photonic structures on omnidirectional and broadband light absorption enhancement in organic solar cells (OSCs) is analyzed using a combination of theoretical simulation and experimental optimization. The photonic structures in the active layer, with a blend system of poly[4,8-bis[(2-ethylhexyl)oxy] benzo[1,2-b:4,5-bA]dithiophene-2,6-diyl][3-fluoro-2-[(2- ethylhexyl)carbonyl]thieno[3,4-b]-thiophenediyl]:[6,6]-phenyl-C70- butyric-acid-methyl-ester (PTB7:PC₇₀BM), were prepared by the nanoimprint method. It shows that the 2-D photonic structures enable not only broadband but also omnidirectional absorption enhancements in the PTB7:PC₇₀BM-based OSCs over a broader angle range of the incident light, leading to >11% increase in the power conversion efficiency, as compared to an optimal planar control cell. A weak angular dependency on light absorption is a unique feature of the photonic-structured OSCs, which is useful for different applications.

中文翻译：

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二维光子结构有机太阳能电池的全向和宽带光吸收增强

结合理论模拟和实验优化，分析了二维光子结构对有机太阳能电池（OSC）全方位和宽带光吸收增强的影响。活性层中的光子结构，具有聚[4,8-双[（2-乙基己基）氧基]苯并[1,2- b：4,5 - b A]二噻吩-2,6-二基的共混体系] [3-氟-2-[（（2-乙基己基）羰基]噻吩并[3,4- b ]-噻吩二基] ：[6,6]-苯基-C70-丁酸甲酯（PTB7：PC ₇₀ BM），是通过纳米压印法制备的。结果表明，二维光子结构不仅可以实现宽带传输，而且还可以增强PTB7：PC _70的全向吸收能力与最佳平面控制单元相比，基于BM的OSC在更宽的入射光角度范围内，导致功率转换效率提高了11％以上。对光吸收的弱角度依赖性是光子结构OSC的独特功能，可用于不同的应用。