Study On ZIF-8 Derived Fe Mesoporous Carbon As Carrier Of 5-Fluorouracil And Electrocatalytic Performance

The rapid growth of the world's population and the deepening of its aging issue,irregular living and eating habits have led to the emergence of non-communicable diseases as the leading cause of global death currently.Among them,cancer is a direct and serious threat to human health.Drug therapy is a very important link and means in the treatment of cancer.The use of effective anticancer drugs can help patients to survive longer and hopefully even cure the cancer completely.However,these anticancer drugs have more or less some detrimental effects on the human body.Therefore,how to reduce the detrimental effects and make them the most likely to play a therapeutic effect has become an urgent problem to be resolved.Hydrogen evolution reaction(HER)and oxygen reduction reaction(ORR)are two important electrochemical reactions for various energy conversion and storage systems.On one hand,hydrogen is an ideal clean energy with high energy density and environmental friendliness,and HER is considered to be one of the most effective method for mass production of high-purity hydrogen.On the other hand,ORR,a key reaction occurring at the cathode of fuel cellsand metal-air batteries,is a major bottleneck which limits the energy conversion efficiency due to its sluggish reaction kinetics and complicated reaction pathway.Pt-based materials have been widely employed as the high-efficiency electrocatalysts for both HER and ORR,but such catalysts suffer from high costs,low Pt utilities,poor stability for long-term operation and so on.Therefore,there is an urgent need to design and develop cheap,efficient and durable catalysts to replace platinum-based catalysts.The main contents of this thesis include the following parts:1?Taking iron acetylacetonate as the magnetic source,using different masses of Zn(NO3)2·6H2O as the metal source,2-methylimidazole as the organic ligand,synthesizing ZIF-8 containing Fe at room temperature,and carbonizing them at different temperatures to prepare a mesoporous carbon material(Znx Fe/NC-y,where x is the mass ratio of Zn(NO3)2·6H2O and iron acetylacetonate added,and y is the calcination temperature).The effects of temperature and metal mass ratio on the morphology and structure of the material were investigated by SEM,TEM,EDX analysis,X-ray diffraction and nitrogen adsorption.It is preliminarily determined that when x is 0.5 and y is 900.The obtained Zn0.5Fe/NC-900 not only retains the unique regular dodecahedral structure of ZIF-8,but also has a large specific surface area and rich mesoporous pores,and has the potential to be employed as a drug carrier and excellent electrocatalyst.And it is the material built a foundation for the follow-up studies.2 ? Using the prepared ZIF-8(Fe)mesoporous carbon as the carrier,5-fluorouracil was loaded on ZIF-8(Fe)by centrifugation and volatile solvent method,and the difference in drug loading upon different methods and different solvents was systematically investigated.The drug-carrier complex with the highest drug loading was selected.ZIF-8(Fe)before and after drug loading was characterized by XRD,Fourier transform infrared spectroscopy(FTIR),thermogravimetry(TG)and differential scanning calorimetry(DSC).It is proved that 5-fluorouracil was successfully loaded into the vector.Finally,different release buffer solvents were selected for the in vitro release assay of ZIF-8(Fe)@5-Fu.The results showed that the drug-carrier complex prepared by loading 5-fluorouracil onto ZIF-8(Fe)had a certain p H selectivity.3 ? Fe-containing mesoporous carbon prepared by using ZIF-8 as a template,and Ru was introduced by Galvanic exchange reaction to prepare core-shell Fe@Ru nanoparticles embedded in nitrogen-doped porous dodecahedral carbon as a catalyst for HER in alkaline electrolyte and ORR in both acid and alkaline electrolytes.By means of SEM,TEM,line scan and EDX mapping,the core-shelled Fe@Ru nanoparticles embedded in porous carbon with normal dodecahedron were fully revealed.A series of electrochemical tests were conducted,and the results showed that Fe@Ru/NC-9% has excellent bifunctional catalytic performance and good stability.Such remarkable electrocatalytic performance could be largely attributable to the distinct Fe@Ru core-shell structure resulted lattice strain atthe interface,in conjunction with the synergistic catalytic effects between the core-shell structure and the porous dodecahedron carbon support.