Synthesis And Properties Of Rare Earth Samarium Luminescent Materials

Rare earth organic complexes have strong absorption intensity in the ultraviolet region,because they mainly transmit energy to the rare earth ions through the intramolecular energy to generate fluorescence emission intensity,and the ligand has an extremely important role in improving the emission intensity of the central rare earth ions.Because of its high fluorescence quantum yield,it has been widely used in medical testing,drug analysis,environmental monitoring and security.In this thesis,rare earth lanthanum was selected as the central metal element,and a series of lanthanum rare earth organic ternary complexes were synthesized,which was successfully compounded on the surface of graphene oxide,and its fluorescence intensity was improved by adding inert rare earth elements.The properties of the above substances were characterized.?1?The GOSs/?Sm-Gd?BA₃Phen composite was successfully synthesized by non-covalent bond.Benzoic acid?BA?was used as the first ligand,and1,10-phenanthroline?Phen?was used as the second synergistic ligand to synthesize the benzoic acid/1,10-phenanthroline quinone heteronuclear rare earth complex.The surface of the graphene oxide is formed by?-?stacking.The composites emit characteristic peaks of rare earth Sm at ⁴G_5/2?⁶H_5/2?563 nm?,⁴G_5/2?⁶H_7/2?596,604 nm?,and ⁴G_5/2?⁶H_9/2?643 nm?,respectively.Produces bright red fluorescence at 365 nm UV light.The luminescence properties of the composites were explored by characterization methods.The results show that the fluorescence intensity of composites increases by 25%and the fluorescence lifetime is 77.64?s.In addition,we also found that in the GOSs/?Sm-Gd?BA₃Phen composite,the best luminescent properties were obtained when n(Sm³⁺):n(Gd³⁺)was 5:5.This work has great research value in the field of graphene oxide functional materials.?2?The GOSs/?Sm-La?TTA₃Phen composite was successfully synthesized by non-covalent bond.?-thiophenecarbonyl trifluoroacetone?TTA?was used as the first ligand,and 1,10-phenanthroline?Phen?was used as the second synergistic ligand to synthesize?-thiophene trifluoroacetone/1,10-phenanthroline is a heteronuclear rare earth complex and acts on the surface of the graphene oxide by?-?stacking.The composites emit characteristic peaks of rare earth Sm at ⁴G_5/2?⁶H_5/2?565 nm?,⁴G_5/2?⁶H_7/2?605,611 nm?,⁴G_5/2?⁶H_9/2?648 nm?,respectively.Produces bright red fluorescence at 365 nm UV light.The luminescence properties of the composites were explored by characterization methods.The results show that the fluorescence intensity of composites increases by 64%and the fluorescence lifetime is 220.67?s.In addition,we also found that in the GOSs/?Sm-La?TTA₃Phen composite,the best luminescent properties were obtained when n(Sm³⁺):n(La³⁺)was 6:4.This work has great research value in the field of graphene oxide functional materials.?3?The GOSs/?Sm-La?DBM₃Phen composite was successfully synthesized by non-covalent bond.Dibenzoylmethane?DBM?was used as the first ligand,and 1,10-phenanthroline?Phen?was used as the second synergistic ligand to synthesize dibenzoylmethane/1,10-phenanthroline A core rare earth complex and acts on the surface of the graphene oxide by?-?stacking.The optical properties of the composites were explored by characterization methods.The composites were ⁴G_5/2?⁶H_5/2?566 nm?,⁴G_5/2?⁶H_7/2?600,611 nm?,⁴G_5/2?⁶H_9/2?647 nm?,where characteristic peak of rare earth Sm emitted,produces bright red fluorescence at 365 nm ultraviolet light.The results show that the fluorescence intensity of composites increases by 131%and the fluorescence lifetime is 121?s.In addition,we have found that GOSs/?Sm-La?DBM₃Phen composites have good electrochemical properties with a capacitance of 2.67 F.And in the GOSs/?Sm-La?DBM₃Phen composite,the best luminescent properties were obtained when n(Sm³⁺):n(La³⁺)was 6:4.This work has great research value in the field of graphene oxide functional materials.