Preparation And Performance Of Hierarchical Mixed Metal Oxides Composites

Due to its unique metal composition and structural properties,nano-composite metal oxides have a wide range of applications in various fields.However,the composition of the metal oxide material is difficult to be controlled,and the structural framework of the material has a significant influence on its properties.In this paper,Mg-Al composite metal oxides at different molar ratios are prepared.The Zn-Al composite metal oxides with biological stem-like structure are prepared using alfalfa as a template.The structure and morphology of the samples are investigated by various characterization methods including XRD,SEM,TEM,FTIR and Zeta potential,and methyl blue adsoprtion and antibacterial properties of composite metal oxides are also studied in detail.Mg-Al LDH with different molar ratios are prepared by hydrothermal method using different molar ratios of magnesium nitrate,aluminum nitrate and urea.Then obtained LDH are processed by high temperature calcination to acquire Mg-Al LDO with different molar ratios oxide.The prepared series of samples have a very pronounced hierarchical structure and hexagonal structure.The study results on the adsorption of methyl blue shows that the prepared LDO with different the moral ratio of Mg and Al have excellent adsorption performance,and the adsorption amount increases with the initial concentration of methyl blue.LDO has the best methyl blue adsorption performance under neutral environment.Raising temperature is advantageous for the adsorption of methyl blue,and the adsorption process can reach equilibrium within 1 h.The adsorption kinetics and adsorption rmodynamic model fittings show that the process of adsorbing methyl blue conforms to the Pse-second kinetic model and the Langmuir thermodynamic model.Meanwhile,these samples are applied to the antibacterial experiment.Mg₃Al LDO has superior antibacterial activity against Escherichia coli（E.coli）and Staphylococcus auras（S.auras）.Using valerian as template,zinc acetate,aluminum nitrate and urea as raw materials,bio-formed Zn-Al LDH is prepared by hydrothermal method,and subjected to high temperature roasting to obtain stalk-like Zn-Al LDO.The experimental study on the adsorption of methyl blue shows that the prepared Zn-Al LDO can be obtained by exploring the most suitable adsorption conditions,including the optimum adsorbent dosage,pH,adsorption concentration and temperature.The prepared samples have excellent removal efficiency and raising temperature is not conducive to the adsorption of methyl blue experiment.Through the adsorption kinetics and adsorption thermodynamic model fitting,it is found that the process of adsorbing methyl blue conforms to the Pse-second kinetic model and the Freundlich thermodynamic model.At the same time,these samples are applied to the antibacterial experiment and the Zn-Al LDO are prepared by the plant template has excellent antibacterial effect against E.coli and S.auras.