Luminescent alkynylplatinum(II) terpyridine-containing conjugated polymers: synthesis, characterization and photophysical studies

Abstract

A series of alkynylplatinum(II) terpyridine complexes and alkynylplatinum(II) terpyridine-containing conjugated polymers with different polymer backbones has been synthesized, and their spectroscopic properties and Förster resonance energy transfer (FRET) processes has been investigated. The platinum(II)-containing polymers exhibit dual emissive features with emission maxima at ca. 416-465 nm and ca. 671-673 nm, which are assigned to be originated from singlet intraligand (¹IL) excited states from the polymer backbone and triplet metal-metal-to-ligand charge transfer (³MMLCT) excited states from the platinum(II) pendants, respectively. The Förster radii (R₀) of the platinum(II)-containing conjugated polymers have been determined, and their distinctive thermo-responsive luminescence changes have also been observed. The present work has demonstrated the utilization of “click” reaction for the preparation of platinum(II)-containing conjugated polymers, which show unique photophysical and spectroscopic properties. Through the judicious design, this type of platinum(II)-containing polymer is found to be sensitive to temperature, resulting in ratiometric emission changes. This study has provided valuable insights into the preparation of metal-containing polymeric systems for different applications.

Keywords

Platinum(II) complexes / conjugated polymers / FRET

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