A monomer (ErQ2(HEMA-CH2-Q)) containing 8-hydroxyquinoline erbium complex was synthesized by two-step coordination reaction.First

a methanol solution of ErCl3 was added to a methanol solution of 8-hydroxyquinoline under stirring with the molar ratio of Er3+/HQ being 1∶2 to obtain ErQ2Cl.Secondly

ErQ2Cl was coordinated with 5-(2-methacryloylethyloxymethyl)-8-quinolinol (HEMA-CH2-Q).Thereafter

novel polymeric Er-complexes were prepared by free radical copolymerization of the monomer and N-vinylcarbazole (NVK).The structure and the properties of the polymeric Er-complexes were studied by elemental analysis

nuclear magnetic resonance spectroscopy (1H-NMR)

Fourier transform infrared spectroscopy (FTIR)

gel permeation chromatography (GPC)

differential scanning calorimetry (DSC)

thermogravimetric analysis (TGA)

UV-Vis absorption spectra

photoluminescence (PL) spectra and PL lifetime.The polymeric Er-complexes involve 8-hydroxyquinoline erbium complex moieties and NVK segments

exhibiting good solubility in a wide range of organic solvents and excellent thermal stability.The glass transition temperature (Tg) and the temperature of 5% weight loss (Td) for the polymeric Er-complexes were around 210℃ and 373℃

respectively.The number average molecular weight of the polymeric Er-complexes was 9000~15000.Excited with UV light of different wavelengths (300

345 and 390 nm)

the polymeric Er-complex emitted the characteristic near-infrared (NIR)-light of ErIII ions.The result indicates that the energy absorbed by carbazole (light-harvesting group) was transferred to 8-hydroxyquinoline (coordinate group)

where it is finally transferred to ErIII ion.In addition

the full width at half maximum (FWHM) in the PL emission spectra of the copolymers was above 90 nm

which enabled a wide gain bandwidth for optical amplification.