RETRACTED: Improving photophysical performance of a Cu(I) complex by doping it into electrospinning composite fibers: Construction, characterization and photophysical analysis

In this paper, a diamine ligand having electron-pulling groups in its conjugation chain and its Cu(I) complex were synthesized and fully characterized, including NMR, single crystal analysis, theoretical calculation and photophysical measurement. It was found that this Cu(I) complex took a distorted tetrahedral coordination field. Its photo-induced electronic transitions had a mixed character of metal-to-ligand-charge-transfer and ligand-to-ligand-charge-transfer. Further analysis indicated that its excited state suffered from severe geometric relaxation. To suppress this geometric relaxation and improve emissive performance, this Cu(I) complex was doped into a polymer matrix through electrospinning method. Performance comparison between bulk sample, solution sample and composite fibrous samples suggested that polymer immobilization effectively suppressed geometric relaxation in excited state and improved its emissive performance, including emission blue shift, longer decay lifetime and improved photostability.