Side-Chain Engineering of Isoindigo-Containing Conjugated Polymers Using Polystyrene for High-Performance Bulk Heterojunction Solar Cells Academic Article uri icon

abstract

  • Developing organic photovoltaic systems that possess high efficiency, high reproducibility, and low cost remains a topic of keen investigation. From a molecular design perspective, developing a "multicomponent" copolymerization synthetic approach could potentially afford macromolecular materials encompassing all of the aforementioned desired parameters. Herein, we describe the synthesis of a series of poly(isoindigo-dithiophene)-based conjugated polymers with varying amounts of low molecular weight polystyrene (PS) side chains (Mn = 1300 g/mol) via random copolymerization. We observed better solubility with polymers containing the PS side chains (when compared to their non-PS-side-chain counterparts), hence leading to better batch-to-batch reproducibility in terms of molecular weights. Furthermore, the PS-side-chain-decorated copolymers also demonstrated better thin film processability, without affecting the electronic and optical properties, when the molar percentage of the PS-containing repeating units were 10%. Bulk heterojunction solar cell devices fabricated with these PS-containing copolymers demonstrated significantly improved performances [maximum power conversion efficiencies (PCE) > 7% and open circuit voltages (VOC) 0.95 V], compared to the highest reported performance (PCE = 6.3% and VOC = 0.70) based on similar isoindigo-containing polymers. Taken together, the synthesis, processing, and device performances of PS-containing copolymers represent a new approach in molecular engineering to achieve a balance between the optical/electronic properties and solubility/processability of reproducible polymeric systems. 2013 American Chemical Society.

published proceedings

  • Chemistry of Materials

altmetric score

  • 0.5

author list (cited authors)

  • Fang, L., Zhou, Y., Yao, Y., Diao, Y., Lee, W., Appleton, A. L., ... Bao, Z.

citation count

  • 127

complete list of authors

  • Fang, Lei||Zhou, Yan||Yao, Yu-Xing||Diao, Ying||Lee, Wen-Ya||Appleton, Anthony L||Allen, Ranulfo||Reinspach, Julia||Mannsfeld, Stefan CB||Bao, Zhenan

publication date

  • December 2013