Zhu Lei, Zhang Ming, Xu Jinqiu, Li Chao, Yan Jun, Zhou Guanqing, Zhong Wenkai, Hao Tianyu, Song Jiali, Xue Xiaonan, Zhou Zichun, Zeng Rui, Zhu Haiming, Chen Chun-Chao, MacKenzie Roderick C I, Zou Yecheng, Nelson Jenny, Zhang Yongming, Sun Yanming, Liu Feng
Frontiers Science Center for Transformative Molecules, In-situ Center for Physical Science, and Center of Hydrogen Science, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, China.
School of Chemistry, Beihang University, Beijing, China.
Nat Mater. 2022 Jun;21(6):656-663. doi: 10.1038/s41563-022-01244-y. Epub 2022 May 5.
In organic photovoltaics, morphological control of donor and acceptor domains on the nanoscale is the key for enabling efficient exciton diffusion and dissociation, carrier transport and suppression of recombination losses. To realize this, here, we demonstrated a double-fibril network based on a ternary donor-acceptor morphology with multi-length scales constructed by combining ancillary conjugated polymer crystallizers and a non-fullerene acceptor filament assembly. Using this approach, we achieved an average power conversion efficiency of 19.3% (certified 19.2%). The success lies in the good match between the photoelectric parameters and the morphological characteristic lengths, which utilizes the excitons and free charges efficiently. This strategy leads to an enhanced exciton diffusion length and a reduced recombination rate, hence minimizing photon-to-electron losses in the ternary devices as compared to their binary counterparts. The double-fibril network morphology strategy minimizes losses and maximizes the power output, offering the possibility of 20% power conversion efficiencies in single-junction organic photovoltaics.
在有机光伏领域，纳米尺度上供体和受体域的形态控制是实现高效激子扩散与解离、载流子传输以及抑制复合损失的关键。为实现这一点，在此我们展示了一种基于三元供体 - 受体形态的双纤维网络，其具有通过结合辅助共轭聚合物结晶剂和非富勒烯受体细丝组件构建的多长度尺度。采用这种方法，我们实现了19.3%的平均功率转换效率（认证值为19.2%）。成功之处在于光电参数与形态特征长度之间的良好匹配，从而有效地利用了激子和自由电荷。该策略导致激子扩散长度增加和复合率降低，因此与二元器件相比，三元器件中的光子到电子的损失最小化。双纤维网络形态策略将损失降至最低并使功率输出最大化，为单结有机光伏实现20%的功率转换效率提供了可能性。
