Tuning the formation of β-phase poly(9,9-di-n-octylfluorenyl-2,7-diyl) via nano-confinement and polystyrene blending for improved photocatalysis

Abstract

Among all the phase morphologies of poly(9,9-di-n-octylfluorenyl-2,7-diyl) (PFO), the β phase exhibits a zigzag coplanar arrangement with the highest conjugation degree. As a result, the β-phasePFO has extraordinary properties, including enhanced charge carrier mobility. In this work, we report the formation of high-β-phase PFO in nanoparticles (NPs) due to the synergistic effect of the slow crystallization of PFO in nanodroplet confinement and polystyrene (PS) blending. The β-phase content of PFO can be flexibly tuned by varying the NP size, molecular weight (Mw), or relative PS content in the NPs. The novel systems demonstrated in this study are likely to provide valuable insights into the β-phase formation mechanism of PFO. As a proof of concept, we further demonstrate that NPs of PFO:PS (1:8) with a higher β-phase content lead to improved photocatalyst efficiency at lower material costs, allowing for novel designs of efficient and visible-light-driven photocatalytic NPs.

Keywords

• Self-assembly
• β-phase formation
• Miniemulsion-solvent evaporation method
• Nanoparticles
• Photocatalysis