【Angew.Chem.】南华大学刘畅、李振业等|H聚集介体把非退火有机太阳能电池效率推到20.8%，PLQY从6.13%升到7.52%#

文章标题：An H‐Aggregation Mediator Enhances Photoluminescence Quantum Yield and Crystallinity for Efficient Nonannealed Organic Solar Cells 文章作者：Hanjian Lai, Huanyan Jiang, Xingjie Mi, Rujin Zhou, Jun Zhang, Zhenghui Luo, Chao Li, Haoran Hu, Yufei Wang, Yuang Fu, Guoli Wang, Xianyong Zhou, Sha Liu, Xinhui Lu, Guangye Zhang, He Yan, Yanming Sun, Zhenye Li, Chang Liu 文章链接：Angewandte Chemie International Edition

非富勒烯受体的“聚集过头”问题#

Y6类非富勒烯受体平面刚性强，成膜时容易面对面堆成H聚集，虽然利于部分电荷传输，却会淬灭发光、压低光致发光量子产率（PLQY）。已有研究多调形貌或解析单晶，很少把H/J聚集方式、发光和光伏性能放在一条因果链上系统验证。本文想用与受体骨架相同的“H聚集介体”NTCl-4F，在非退火条件下同时提高PLQY和结晶性。

Fig.1 (a) Molecular structures of D18, L8-BO-C4, and NTCl-4F. (b, c) The molecular binding energies calculated by density functional theory. (d) PLQY of L8-BO-C4, L8-BO-C4: NTCl-4F and NTCl-4F film. (e, f) UV–vis-NIR absorption spectra of D18, L8-BO-C4, NTCl-4F, L8-BO-C4: NTCl-4F, D18 and D18: L8-BO-C4: NTCl-4F, films. (g) The corresponding 2D in situ UV–visible absorption profiles of L8-BO-C4, L8-BO-C4: NTCl-4F, D18: L8-BO-C4 and D18: L8-BO-C4: NTCl-4F blend during spin-coating. (h) Temporal evolution of the peak positions, intensities, as well as the derivatives of peak position and intensity during spin coating.

介体如何改写聚集与器件数据#

作者把NTCl-4F加入D18。单晶显示其中心核二面角4.87°，中心核空间位阻使核心-核心堆积受阻，只保留端-端和核心-端堆积，形成较松的三维网络。原位吸收显示成膜结晶时间从0.71秒缩短到0.35秒，约740 nm的H聚集吸收带减弱，共混膜吸收红移；受体纯膜PLQY从6.13%升到7.52%。GIWAXS中面内和面外晶体相干长度分别从100.98 Å升到120.32 Å、从19.84 Å升到21.50 Å；PiFM显示受体富集纤维细化到11.00 nm。器件在10 wt% 添加量下，非退火D18:L8-BO-C420.8%，对照为19.4%；VOC从0.89 V升到0.92 V，JSC从27.3升到27.9 mA cm⁻²，FF从78.9%升到80.5%。PM618.19%升到19.45%，D18。但PLQY只提高1.39个百分点，效率提升同时伴随能级、形貌和结晶性变化，原文的关联分析不能单独证明PLQY是主因；20 wt%添加反而下降，说明窗口较窄。

Fig.2 (a) Molecular packing configurations of the D18: L8-BO-C4: NTCl-4F blend active layer; (b–c) Two-dimensional GIWAXS patterns and one-dimensional integrated scattering profiles in the OOP and IP directions; (d) π-π stacking distances and CCL values for the corresponding films; (e) π–π stacking distances and CCL values for D18: L8-BO-C4 and D18: L8-BO-C4: NTCl-4F films, as well as the 2Rgc, Df, and Xdab values fitted from GISAXS; and (g) in-plane GISAXS linecuts of D18: L8-BO-C4 and D18: L8-BO-C4: NTCl-4F films. Fig.5 (a) J–V characteristic curves, (b) Statistic PCE for PM6: Y6, PM6: Y6: NTCl-4F, D18: Y7 and D18: Y7: NTCl-4F devices. (c) PLQY of Y6, Y6: NTCl-4F, Y7 and Y7: NTCl-4F film. (d) EQEEL of PM6: Y6, PM6: Y6: NTCl-4F, D18: Y7 and D18: Y7: NTCl-4F devices. (e) The corresponding 2D in situ UV–visible absorption profiles of PM6: Y6, PM6: Y6: NTCl-4F, D18: Y7 and D18: Y7: NTCl-4F blend during spin-coating.

能用到哪一步#

这项工作把“聚集方式工程”做成可操作的分子介体策略，给非退火、可溶液加工有机光伏提供了一条不靠热退火提效的路径。但证据仍限于实验室小面积器件和有限加速老化，户外长期稳定性、放大涂布和批次一致性原文未提供直接数据；NTCl-4F与L8-BO-C4骨架相同，换体系是否需重新设计介体也未回答。它更像一个机理清晰的形貌调控案例，而不是已可量产的配方。