Design And Synthesis Of Phosphorescent Terpyridine Iridium(?) Complexes And Their Applications In Stimuli-Responsive Materials And Supramolecular Self-Assembly

Recently,luminescent transition metal complexes have been successfully applied in diverse optoelectronic applications such as organic light-emitting diode,light emitting electrochemical cell,chemical sensing,bioimaging,and so on.Therefore,it is of great scientific and practical significance to develop luminescent transition metal complexes with excellent photophysical properties.Terpyridine and its derivates can coordinate with most of transition metal ions to form stable metal complexes.This calss of metal complexes have attracted increasing attentions due to their excellent photophysical properties and rich electrochemical properties.Recently,terpyridine metal complexes have been successfully applied in stmuili-responsive materials,supramolecular self-assembly,optical information recording.In this thesis,firstly,a terpyridine iridium?III?complex has been designed and synthsized to study the influence of external stimuli on its photophysical peroperties.In addition,terpyridine iridium?III?and zinc?II?complexes have been designed and prepared,the self-assembly properties of those complexes have been studied in detail.The main contents are summarized as the following:1.Constructing stmuili-responsive luminescnect materials through photo-induced electron transferWe have designed and synthesized an electron-deficient phosphorescent bis-terpyridine iridium?III?complex,which can form an ion pair complex with electron-rich tetrabutylammonium borohydride.UV-visible absorption spectra,transient absorption spectra and photoluminescence spectra were employed to study the photophysical properties of this complex,and the excited-stated quenching mechanism has been confirmed.In addition,it is found that the external electrical stimulus and UV irradiation can result in siginifcant luminescence changes.Upon application of a voltage,BH₄^-near the anode would be oxidized and thus led to an increase in the emission intensity,and the effect of Cu²⁺on luminescence recovery is eliminated.Based on this electrochromic luminesecence property,an optical data recording device has been successfully constructed.Moreover,singlet oxygen would be generated upon continuous UV irradiation,which can oxidize BH₄^-and give rise to luminesecnece recover of iridium?III?complex.2.The study on self-assembly and photoluminsecence color tuning of terpyrinde iridium?III?/zinc?II?complexesWe have designed and synthesized bis-terpyridine iridium?III?complex with red emission color and zinc?II?complex with green emission color for supramolecular self-assembly.Photoluminescence spectra was employed to study the photophysical properties of the two complexes.By tuning the ratio of iridium?III?and zinc?II?complex,self-assembled nanomaterials with different morphologies and luminescent colors can be obtained in n-propanol/water.Scanning electron microscopy and transmission electron microscopy have demonstrated the nanosheet and nanosphere morphologies,and explore their self-assembly mechanism:?-?stacking interactions and hydrophobic interaction respectively.Furthermore,confocal fluorescence and emission lifetime imaging were emolyed to study the emission color and lifetime changes of different nanomaterials.