Design, Synthesis And Functional Regulation Of Bipyridyl Fluorescent Materials

Fluorescent materials are widely used in lighting,display and detection fields.Massive new kinds of fluorescence material are discovered with the scope of research on luminescence has gradually expanded.Among the many fluorescent materials,the materials involved in pyridine are also varied.This is because bipyridine materials possess unique chemical stability,redox properties,reactivity of excited states,luminescent properties and suitable lifetimes of excited states.Therefore,bipyridine materials play a great role in photochemistry,photophysics,photocatalysis,electrochemistry,photochemistry,chemistry and electrochemiluminescence.Based on 4,4'-bipyridine and 2,2'-bipyridine in bipyridine materials,a series of organic fluorescent materials and organic-inorganic hybrid fluorescent materials were prepared to explore the effect of fluorescence regulation on bipyridine fluorescent materials.The content of this thesis is divided into two parts.The Part I is that neutral molecules are inserted into compounds formed mainly around 4,4'-bipyridine and metal halides to realize band gap regulation of materials,which can achieve the purpose of fluorescence control.The Part II contains Six organic fluorescent materials obtained by further reaction of 2,2'-bipyridine.And by comparing the band gap of these materials with the multidirectional fluorescence properties,we realize the fluorescence regulation of 2,2'-bipyridine materials.The details are as follows.?1?3 novel bismuth?III?-chloro-based inorganic-organic hybrid materials containing4,4'-bipyridine were synthesized:[HEV][BiCl₅]?1?,[MV]₃[Bi₄Cl₁₈]·[C₁₆H₁₀]?2?and[MV]₃[Bi₄Cl₁₈]·[C₂₀H₁₂]?3?(N-protonN'-ethyl-4,4'-bipyridinium;[MV]²⁺=N,N'-dimethyl-4,4'-bipyridinium).They all contain the cation of bipyridine and the anion of bismuth?III?chlorine.Beside,the neutral luminescent groups of pyrene and pyrene were successfully introduced.The crystal structure and other physicochemical properties of the three materials were also characterized.?2?Regulating the fluorescence emission via inserting neutral organic molecules.With the increase of organic molecular components,the band gap gradually becomes smaller.The measurements showed that the three compounds had wide yellow,red and orange light emission bands and the redshift of maximum fluorescence emission peak increase with the organic parts increasing.?3?6 novel organic fluorescent materials containing 2,2'-bipyridine were synthesized:BIPY,BIPYT,BIPY2T,BNBP,BNBPT and BNBP2T.Further,their physical and chemical properties were also characterized.?4?The addition of thiophene group increases the conjugate length of the material;The space structure and electronic characteristics of the materials are controlled by the increase of boron atomic coordination;By introducing B?N groups,the red shift of the corresponding materials occurred.All in all,it shows that the fluorescence regulation of this kind of material is realized.?5?Theoretical calculations show that the Value of HOMO/LUMO of three compounds?BIPY,BIPYT,BIPY2T?decreases gradually.Similarly,as the length of units of BNBP,BNBPT and BNBP2T increases,their value of HOMO/LUMO decreases significantly.Those all provide a reliable theoretical basis for the regulation of fluorescence in this paper.?6?Using the principle of CIE,the white light control can be realized by mixing BIPYT with one of the three:BNBP,BNBPT and BNP2T in a certain proportion.