Energy transfer from fluorene‐based conjugated polyelectrolytes to on‐chain and self‐assembled porphyrin units

Abstract

A new water soluble fluorene‐based polyelectrolyte containing on‐chain porphyrin units has been synthesized via Suzuki coupling, for use in optoelectronic devices. The material consist of a random copolymer of poly{1,4‐phenylene‐[9,9‐bis(4‐phenoxy butylsulfonate)]fluorene‐2,7‐diyl} (PBS‐PFP) and a 5,15‐diphenylporphyrin (DPP). The energy transfer process between the PBS‐PFP units and the porphyrin has been investigated through steady state and time‐resolved measurements. The copolymer PBS‐PFP‐DPP displays two different emissions one located in the blue region of the spectra, corresponding to the fluorene part and another in the red due to fluorescent DPP units either formed directly or by exciton transfer. However, relatively inefficient energy transfer from the PFP to the on‐chain porphyrin units was observed. We compare this with a system involving an anionic blue light‐emitting donor PBS‐PFP and a anionic red light‐emitting energy acceptor meso‐tetrakisphenylporphyrinsulfonate (TPPS), self‐assembled by electrostatic attraction induced by Ca2+. Based on previous studies related to chain aggregation of the anionic copolymer PBS‐PFP, two different solvent media were chosen to further explore the possibilities of the self‐assembled system: dioxane–water and aqueous nonionic surfactant n‐dodecylpentaoxyethylene glycol ether (C12E5). In contrast, with the on‐chain PBS‐PFP‐DPP system the strong overlap of the 0‐0 emission peak of the PBS‐PFP and the Soret absorption band of the TPPS results in an efficient Förster transfer. This is strongly dependent on the solvent medium used. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Nonlinear Optical Materials for the Smart Filtering of Optical Radiation

“…Porphyrins (Pors) are an all-pervading class of naturally occurring compounds with important biological representatives such as hemes, chlorophyll, and Vitamin B12. A basic structure of a Por macrocycle consists of four pyrrolic subunits linked by four methine bridges, and it is considered a related compound from Pcs. − Por synthesis has been extensively improved over the years, − and studied for a vast array of applications, including catalysis, − photomedicinal applications, − energy transfer, − and others. − …”

A Cost-Efficient Method for Unsymmetrical Meso-Aryl Porphyrin Synthesis Using NaY Zeolite as an Inorganic Acid Catalyst

“…Owing to porphyrin’s myriad of applications, including biomedicine [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 ], catalysis [ 9 , 10 , 11 , 12 ], and materials [ 13 , 14 , 15 , 16 , 17 , 18 ], the preparation of unsymmetrically substituted porphyrins, bearing bridgeable groups for further linkage to other chemical entities and materials, is of utmost interest [ 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]. Unsymmetrically substituted porphyrin design has been applied for several decades, at first, using porphyrin β-pyrrolic substituting patterns such as the 3+1 route [ 27 , 28 , 29 ], employing the chemistry proposed in the well-known MacDonald 2+2 method [ 30 ], which essentially relied on the cumbersome synthesis of tripyrranes [ 31 ], later mitigated by Sessler’s advances on their syntheses [ 32 ].…”

Red and near infrared fluorescent conjugated polyelectrolytes for biomedical applications

“…The commonly used polymerization methods for red and NIR CPEs are listed in Figures and , which include direct polymerization methods (e.g., Suzuki coupling, Heck coupling, Sonogashira coupling, Knoevenagel condensation, and FeCl 3 ‐catalyzed oxidative polymerization .…”