Side-Chain Engineering in ITIC Skeleton Enabling As-Cast Organic Solar Cells with Reduced Energy Loss and Improved Vertical Phase Distribution

作者：Jintao Zhu, Li Lv, Tingting Dai, Run Pan, Fan Wang, Jiaqi Yang, Hainam Do, Erjun Zhou, Zhi‐Kuan Chen, Fei Chen · 发表于：ACS Materials Letters · 年份：2024 · DOI：10.1021/acsmaterialslett.4c00287 · 被引用次数：12 · 研究领域：Organic Electronics and Photovoltaics、Perovskite Materials and Applications、Conducting polymers and applications

Constructing binary organic solar cells (OSCs) with remarkable open-circuit voltage ( V OC ) as well as suppressed energy loss ( E Loss ) has been considered a promising strategy for breaking the efficiency bottleneck for OSCs. In this work, two novel chlorinated fused-ring electron acceptors were designed and synthesized through side-chain engineering, of which the rotation of end-capping groups on the indenedithiene [3,2- b ] thiophene core was effectively restricted. Benefiting from the conformation lock, the IMC6–4Cl and IMC8–4Cl binary donor/acceptor (D/A) blend films realized more ordered molecular stacking and reduced Urbach energy, leading to lower E Loss of the devices. Moreover, the prolonged side chains in IMC8–4Cl inhibited excessive aggregation of the molecules and facilitated better miscibility with D18. Therefore, the D18:IMC8–4Cl blend films exhibited more rational D/A phase separation and reduced energy disorder. Eventually, the D18:IMC8–4Cl based devices achieved an exceptional power conversion efficiency of 13.99% and a decent V OC of 0.97 eV.