| The discovery and use of antibiotics play a vital role in the development of human society.As a class of antibiotics,the residues of tetracycline antibiotics in the water environment can lead to a series of ecological,environmental and human health problems.Therefore,it is urgent to find an effective way to deal with the pollution of tetracycline antibiotics.The use of semiconductor photocatalytic degradation technology in tetracycline class antibiotics pollution,because of the characteristics of high efficiency and low toxicity,has become a more application prospects.However,most of the semiconductor photocatalyst has many defects,which greatly limits its application in the actual production and life.For example,the light response range is narrow?only4%of sunlight energy can be used?,and quantum efficiency is low.Based on this,the researchers focused more on the research and development of photocatalysts that use light efficiently.The study found that uranyl ions can be inspired to form catalytic activity centers under light,and the active center has a strong oxidizing,which can oxidize organic pollutants to realize effective degradation of pollutants.Uranyl complexes are used for the degradation of antibiotic pollutants in wastewater.It provides a feasible way for the treatment of antibiotic pollutants in the environment.At the same time,it also provides an effective place for the disposal of nuclear waste,so that nuclear waste can be turned into a treasure.Therefore,it is great significant to synthesize different uranyl complexes and to study the catalytic properties of photocatalytic materials.11 cases of uranyl complexes were synthesized in this paper:?H2-bpp?[?UO2??p-nba?3]2?1?,?H2-bpy?[?UO2?4??3-O?2?p-nba?6]?2?,[?UO2?2?ntp?2]?bpp??3?,?H2-bpe?[?UO2?2?ntp?3]·2H2O?4?,?H2-tmp?[?UO2??ntp?2]·H2O?5?,?H3O?2[?UO2?2?ndc?3]·H2O?6?,?H2-bpp?[?UO2?2?ndc?3]·EtOH·5H2O?7?,?H2-bpe?2/2[?UO2?2?ndc?3]·EtOH?8?,?H2-bpp?[?UO2?2?ndc?3]·5H2O?9?,?H2-bpp?[?UO2??Hndc??ndc?]2·2H2O?10?and?H2-bpy?[?UO2??ndc?2]?11??Hp-nba:p-nitrobenzoic acid,H2ntp:nitroterephthalic acid,H2ndc:1,4-naphthalene dicarboxylic acid,bpy:4,4?-bipyridine,bpp:1,3-di?4-pyridyl?-propane,bpe:1,2-Vinylenedipyridine,tmp:tetramethylpyrazine?.The above-mentioned uranyl complexes were used as photocatalyst respectively and tetracycline antibiotics are used as degradation targets for photocatalytic performance in ultraviolet or visible light.The research work of this paper can be divided into three parts:The first part is the synthesis of two complexes 1 and 2 with p-nitrobenzoic acid as ligands.And we studied the properties of tetracycline hydrochloride antibiotics.The optimum concentration of photocatalytic degradation and kinetics of the reaction process were investigated.The results showed that the optimal dosage concentration was 1.0 mg/mL,and it conforms to the first order kinetic model.In addition,their cyclic stability was investigated.In the second part,three cases of uranyl terephthalate complexes were synthesized by solvent-hydrothermal method.The complexes 3 and 4 were 2D structures,and the complex 5 were3D structures.They showed good degradation activity of tetracycline hydrochloride under the visible light.At the same time,the degradation effect of complex 4 on the other tetracycline antibiotics?chlorotetracycline,oxytetracycline,deoxytetracycline et al.?was also studied.The results suggest that it had similar degradation activity to different tetracycline antibiotics.In the third part,six cases of 1,4-naphthalene dicarboxylic complexes were prepared in different solvents and their photocatalytic properties were studied.Under the irradiation of ultraviolet light,the six cases showed a better catalytic effect with the highest up to 95%.And the degradation process conforms to the first order kinetic model.In addition,density functional theory is used to calculate these six complexes.They were analyzed from the molecular orbitals,the absorption spectra,and natural bond order three parties.The factors affecting photocatalytic performance were discussed in terms of the energy difference of the HOMO-LUMO,structure and the number of active sites. |
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