Comparative study on triphenylamine-based bi-armed and four-armed small molecule donors for solution processed organic solar cells

作者：Zhen Hongyu^*; Peng Zuosheng; Hou Lintao; Jia Tao; Li Qi; Hou Qiong

来源：Dyes and Pigments, 2015, 113: 451-457.

DOI：10.1016/j.dyepig.2014.09.005

• Four-armed molecule
• Triphenylamine-based molecules
• Miscibility
• Organic solar cells
• Bulk heterojunction
• Small molecule donor

A novel four-armed triphenylamine (TPA)-based molecule named (TPATh)(4)TPA(2)B with 4,7-bis(4-diphenylaminophenyl)-2,1,3-benzothiadiazole unit as the central building block and triphenylamine-3-dodecylthiophene unit as the arms and a bi-armed TPA-based molecule named (TPATh)(2)(MTPA)(2)B with the same central building block and arms as those of (TPATh)(4)TPA(2)B were designed and synthesized by Pd-catalyzed Stille reaction. The thermal stability, photophysical and electrochemical properties of these small molecules are studied. Moreover, they are evaluated in solution processed bulk-hetero-junction organic solar cells (OSCs). The device performances of the OSCs based on these small molecule donors and [6,6]-phenyl-C-71-butyric acid methyl ester (PC71BM) were studied. With the same core, the four-armed molecule has the higher absorption and better miscibility with PC71BM than that of bi-armed molecule, while the bi-armed molecule (TPATh)(2)(MTPA)(2)B has the higher hole mobility. The power conversion efficiency of the OSCs based on (TPATh)(4)TPA(2)B as donor and PC71BM as acceptor is 1.3% with open-circuit voltage 0.71 V.

• 单位
  华南师范大学; 华南理工大学; 济南大学; 暨南大学; 浙江大学