分子取向调控对有机太阳电池器件性能的提升

郭丰; 钟天; 喻康林; 雷诗云; 张明睿; 肖标; 胡黎文; 王亮

doi:10.13801/j.cnki.fhclxb.20220222.001

分子取向调控对有机太阳电池器件性能的提升

doi: 10.13801/j.cnki.fhclxb.20220222.001

江汉大学　光电材料与技术学院光电化学材料与器件教育部重点实验室，武汉 430056

基金项目: 国家自然科学基金 (52103213；21302064)；中央引导地方科技发展专项(2019ZYYD005)

详细信息

作者简介:
肖标，博士，副教授，硕士生导师，江汉大学光电化学材料与器件教育部重点实验室。2015年6月获华南理工大学高分子化学与物理专业博士学位。主要从事聚合物太阳能电池及量子点发光二极管相关科研工作，主持国家自然科学基金、中国博士后科学基金、湖北省自然科学基金等课题7项。已在国际一流学术期刊上发表SCI论文30余篇，论文引用次数超过2 000次，授权发明专利8项（E-mail: biaoxiao@jhun.edu.cn）

通讯作者:
肖标，博士，副教授，硕士生导师，研究方向为光电化学材料与器件　E-mail: biaoxiao@jhun.edu.cn

胡黎文，博士，讲师，研究方向为共轭光电材料的合成　E-mail: hulw@jhun.edu.cn

王亮，博士，副教授，硕士生导师，研究方向为新型光电材料的合成　E-mail: wangliang@mail.jhun.edu.cn

中图分类号: TM914.4
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出版历程
- 收稿日期: 2021-12-01
- 修回日期: 2022-01-25
- 录用日期: 2022-01-30
- 网络出版日期: 2022-02-23
- 刊出日期: 2022-03-23

Improved device performance enabled by optimized molecular orientation in organic solar cells

Key Laboratory of Optoelectronic Chemical Materials and Devices (Ministry of Education), School of Optoelectronic Materials & Technology, Jianghan University, Wuhan 430056, China

摘要

摘要: 活性层形貌对有机太阳电池的器件效率有着重要的影响。调控活性层中的分子取向是优化其形貌的方式之一。本文旨在采用Layer-by-Layer (LbL)的方法调控有机太阳电池活性层中分子的取向，进而提升电池器件的效率。通过向电子受体中加入不同的添加剂实现活性层中受体分子(Y6)的取向调节，优化后器件的能量转换效率达到16.2%。利用椭圆偏振光谱和掠入射广角X射线散射(GIWAXS)技术对活性层薄膜进行了表征，结果表明，向受体中加入1, 8-二碘辛烷(DIO)作为添加剂后，活性层中的Y6分子倾向水平取向，向受体中加入氯萘(CN)作为添加剂后，Y6分子倾向于垂直取向。电学和光学表征结果表明，Y6的水平取向增加了器件内激子的分离效率，进而提升了器件的能量转换效率。
- 有机太阳电池 /
- 逐层沉积 /
- 分子取向 /
- 椭圆偏振光谱 /
- 掠入射广角X射线散射 /
- 受体分子 (Y6)
Abstract: The morphology of the active layer has an important influence on the device efficiency of organic solar cells. Tuning the molecular orientation in the active layer is one of the ways to optimize its morphology. This paper aims to use a Layer-by-Layer (LbL) method to regulate the orientation of molecules in the active layer of organic solar cells, thereby improving the efficiency of cell devices. By adding different additives to the electron acceptor, the orientation of acceptor molecule (Y6) in the active layer is adjusted, and the energy conversion efficiency of the optimized device reaches 16.2%. The active layer films were characterized by ellipsometry and grazing incidence wide-angle X-ray scattering (GIWAXS). The results show that after adding 1,8-diiooctane (DIO) as an additive to the receptor, Y6 molecules in the active layer tend to be horizontally oriented, and after adding chloronaphthalene (CN) as an additive to the receptor, Y6 molecules tend to be vertically oriented. The electrical and optical characterization results show that the horizontal orientation of Y6 increases the exciton separation efficiency, and then improves the energy conversion efficiency of the device.
- organic solar cell /
- Layer-by-Layer /
- molecular orientation /
- ellipsometry /
- GIWAXS /
- acceptor molecule (Y6)

HTML全文

图 1 (a)器件电流密度-电压曲线图；(b)器件的外量子效率图(EQE)；(c)受体分子(Y6)薄膜在添加不同添加剂时的紫外-可见吸收光谱图；(d)通过Layer-by-Layer (LbL)方式制备的聚合物PBDB-T-2F (PM6):Y6薄膜的紫外-可见吸收光谱图，插图为(d)图在长波峰值处的放大图

Figure 1. (a) Current density-voltage curve of device; (b) External quantum efficiency (EQE) diagram of the device; (c) UV-vis absorption spectra of acceptor molecule (Y6) film with different additives; (d) UV-vis absorption spectra of PBDB-T-2F (PM6):Y6 films prepared by Layer-by-Layer (LbL) method, Figure (d) is a magnified view at the long wave peak

下载: 全尺寸图片幻灯片

图 2 (a) 不同条件制备的薄膜的二维掠入射广角X射线散射图像；(b) 薄膜在面内(In plane)和面外(Out of plane)方向上的积分曲线

Figure 2. (a) 2D grazing incidence wide-angle X-ray scattering images of films prepared under different conditions; (b) Integral curves of the film in and out of plane directions

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图 3 PM6:Y6 (a)、PM6:Y6+CN (b)、PM6:Y6+DIO (c)三种薄膜的n、k曲线图；(d)三种薄膜中分子取向示意图

Figure 3. n and k curves of PM6:Y6 (a), PM6:Y6+CN (b), PM6:Y6+DIO (c) films; (d) Schematic diagram of molecular orientation in three thin films

n_o, n_e—Refractive indices of light parallel and perpendicular to the plane of incidence; k_o, k_e—Extinction coefficients of light parallel and perpendicular to the plane of incidence; S—Hermans orientation parameter

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图 4 (a) 器件光生电流-有效电压图；(b) 器件的开路电压-光强关系曲线；器件在较大有效电压(1 V) (c)和较小有效电压(0.1 V) (d)时的光生电流-光强曲线图

Figure 4. (a) Photogenerated current-effective voltage diagram of the device; (b) Open-circuit voltage-light intensity relationship curve of the device; Photogenerated current-light intensity curves of the device at a large effective voltage (1 V) (c) and a small effective voltage (0.1 V) (d)

V_eff—Effective voltage; J_ph—Photocurrent density

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表 1 器件基本性能参数表

Table 1. Basic performance parameters of the device

	PCE/%	V_oc/V	FF/%	J_sc/(mA·cm⁻²)
PM6:Y6	15.16	0.85	68.87	25.90
PM6:Y6+CN	15.01	0.86	71.62	24.36
PM6:Y6+DIO	16.24	0.82	74.80	26.35
Notes: PCE—Power conversion efficiency; V_oc—Open-circuit voltage; FF—Fill factor; J_sc—Short-circuit current density.

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