| Metal-organic frameworks(MOFs)are porous crystal materials with a periodic network structure formed by self-assembly of metal ions and organic ligands by coordination bonding.Due to its variable topological structure and physicochemical properties,MOFs materials have many remarkable properties and are widely used in many fields,such as drug carriers and energy reserves.Due to poor water solubility of some drugs,increasing the solubility of insoluble drugs is one of the important areas of pharmaceutics research.Mesoporous carbon materials have good biocompatibility,rich pore structure and good stability.Therefore,mesoporous carbon materials are a kind of drug carrier materials widely concerned by researchers.As the different morphology and pore structure of MOFs,the mesoporous carbon material prepared by calcining MOFs is an excellent drug carrier.Rechargeable lithium/sodium ion batteries with high energy density,long cycle life and excellent rate capability have been considered as promising power sources for portable electronic devices.In recent years,the transition metal selenides have been found to provide much larger theoretical specific capacity than carbonaceous materials and is considered to be a promising lithium/sodium ion battery with high capacity anode material.Such electrode materials usually need to be compounded with carbon materials.And MOFs are ideal templates to synthesis the transitional selenide/carbon composites with unique microstructure.In this paper,the carbon composites was synthesized,using the metal organic frame ZIF-8 or ZIF-67 as the precursor,as the anode material of lithium/sodium ion battery and the drug carry.The specific works are as follows:1.The mesoporous carbon prepared by the Co-based zeolite imidazole metal organic framework(ZIF-67)was combined with graphene oxide to prepare a magnetic mesoporous carbon material with an ultra-large specific surface area of 804.66 m2/g,and the material was studied for adsorbing poorly soluble drug ketoconazole by the drug release experiment.The results of adsorption experiments showed that the drug loading of CoNC@r GO-2h was up to 10.7 %.In the release experiment,the cumulative release of Co-NC@r GO-2h within 180 min reached 75.5 %,much higher than the 33.2% of the drug substance.And the release of the drug was almost completed after 40 min.2.ZIF-8 was synthesized from Zn(NO3)·6H2O as metal source and 2-methylimidazole as organic ligand,and ZIF-8 was selenized at 600 °C with selenium powder.And the electrochemical performance was tested as a negative electrode material for lithium ion batteries.The results of XRD,SEM and TEM showed that the core-shell Zn Se@C was successfully synthesized,and the results of XPS and Raman spectroscopy indicated the effect of holding time on the external carbon layer.3.Zn Se@C core-shell nanocomposite was used as the negative electrode material to assemble the battery using two electrolytes,ether and carbonate electrolyte,respectively.Zn Se@C has a specific capacity of 617.1 m Ah/g after 800 cycles at a current density of 1 A/g in ether electrolyte,which is much better than carbonate electrolyte.The more stable SEI films are formed on Zn Se@C in ether electrolyte,which is responsible for the excellent cycling stability of LIBs in ether electrolyte..4.We used ascorbic acid to reduce graphene oxide to wrap the material to synthesize Zn Se@r GO composite with three-dimensional conductive structure.Zn Se@r GO-10:1 exhibits excellent electrochemical performance as a negative electrode for sodium ion batteries.At a super current density of 5 A/g,the specific capacity is still 223.7 m Ah/g after 1000 cycles,and the capacity retention rate is 90.4%.The experimental results show that the improvement of the mechanical strength by graphene encapsulation can effectively improve the electrochemical performance of the material. |
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