Open AccessFine Optimization of Morphology Evolution Kinetics with Binary Additives for Efficient Non‐Fullerene Organic Solar Cells
Author(s) -
Chen Jianya,
Bi Zhaozhao,
Xu Xianbin,
Zhang Qianqian,
Yang Shengchun,
Guo Shengwei,
Yan Hongping,
You Wei,
Ma Wei
Publication year - 2019
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.201801560
Subject(s) - materials science , morphology (biology) , photoactive layer , solvent , organic solar cell , chemical engineering , energy conversion efficiency , kinetics , polymer solar cell , fullerene , phase (matter) , polymer , organic chemistry , optoelectronics , composite material , chemistry , genetics , physics , quantum mechanics , engineering , biology
Abstract The power conversion efficiency of polymer solar cells (PSCs) is strongly affected by active layer morphology. Here, two solvent additives (ODT: octance‐1,8‐dithiol; DIO: 1,8‐diiodooctane) are used to optimize the bulk heterojunction morphology of FTAZ:ITIC‐Th based PSCs and ≈11% efficiency is obtained, which is 10% higher than the untreated device. Based on the morphological characterizations, the influence of binary solvent additives on manipulating molecular packing and phase separation of blend films is successfully revealed. More importantly, in situ grazing incidence wide‐angle X‐ray scattering characterization is adopted to explore the crucial role played by these two solvent additives at different stages of the film‐forming process, that is, ODT influences the initial stage of the film‐forming process, while DIO later establishes the ultimate photoactive film formation. Due to the impacts of two additives at different film processing stages, an optimal ratio of ODT:DIO (0.375%:0.125%) is obtained, which helps in realizing the optimized morphology.