Li Min, Xiao Manjun, Li Zuojia
Jiangxi Province Key Laboratory of Polymer Micro/Nano Manufacturing and Devices, School of Chemistry, Biology and Materials Science, East China University of Technology Nanchang 330013 P. R. China
School of Materials Science and Engineering, Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications, Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering, National Experimental Demonstration Center for Materials Science and Engineering, Changzhou University Changzhou 213164 China
RSC Adv. 2021 Dec 13;11(63):39625-39635. doi: 10.1039/d1ra08239f.
Three novel A-D-A type small-molecule donor materials, namely AAN-DPP, AAN(T-DPP) and AANT(T-DPP), with anthanthrene (AAN) as the electron-donating core, diketopyrrolopyrrole (DPP) as the electron-accepting moiety, and thiophene as π-bridge units, have been designed and synthesized for application in bulk-heterojunction (BHJ) organic solar cells (OSCs). Compared to AAN-DPP, devices based on AAN(T-DPP) and AANT(T-DPP) show better photovoltaic performance due to broader absorption and better planarity of the molecular backbone. A maximum power conversion efficiency (PCE) of 2.33% with a short-circuit current density ( ) of 6.82 mA cm and a fill factor (FF) of 39.80 was obtained in the AAN(T-DPP)/PCBM-based solar cells. This is resulting from the suitable thickness of the active layer, improving the ability of catching light and decreasing the twist angle of the backbone by inserting a thiophene spacer. The results indicate that strategic substitution of π-bridges and side-chains in A-D-A type SMs is an efficient strategy to improve photovoltaic performance.
设计并合成了三种新型A-D-A型小分子给体材料，即AAN-DPP、AAN(T-DPP)和AANT(T-DPP)，它们以蒽嵌蒽酮（AAN）作为给电子核心，二酮吡咯并吡咯（DPP）作为电子接受部分，噻吩作为π桥单元，用于体相异质结（BHJ）有机太阳能电池（OSC）。与AAN-DPP相比，基于AAN(T-DPP)和AANT(T-DPP)的器件表现出更好的光伏性能，这是由于分子主链具有更宽的吸收和更好的平面性。在基于AAN(T-DPP)/PCBM的太阳能电池中，获得了2.33%的最大功率转换效率（PCE），短路电流密度（ ）为6.82 mA cm，填充因子（FF）为39.80。这是由于活性层的合适厚度、提高了捕光能力以及通过插入噻吩间隔基团降低了主链的扭转角。结果表明，在A-D-A型小分子中对π桥和侧链进行策略性取代是提高光伏性能的有效策略。
