Polymer immobilization effect on excited state of emitting copper complex: Synthesis, characterization and performance improvement

Abstract In this effort, the correlation between polymer immobilization effect and excited state of emitting copper complex was discussed. An electron-pulling diamine ligand having an oxadiazole ring and a fluorine atom was synthesized. Its corresponding Cu(I) complex was synthesized with a phosphorous ligand (PPh 3 ) having obvious steric hindrance as auxiliary ligand. Its geometric structure, electronic transition and photophysical parameters were discussed in detail. A distorted tetrahedral coordination field was adopted by this Cu(I) complex. Its onset electronic transition was confirmed as a charge transfer one and suffered from structural relaxation badly. Using electrospinning method, this Cu(I) complex was dispersed and immobilized into a polymer host so that structural relaxation of its excited state could be limited. A systematical comparison between various states of this complex, in solution, in solid state and in fibrous samples, was performed. It was finally confirmed that this polymer matrix served as a promising supporting host, offering a rigid and protective microenvironment for dopant molecules which effectively limited their MLCT structural relaxation and improved their photostability.