Synthesis And Adsorption Performance Research Of Hexagonal Boron Nitride

As a kind of the most important inorganic non-metallic materials,boron nitride materials a series of excellent performance characteristics including excellent physical and chemical properties,especially have the good mechanical properties,high thermal conductivity,chemical stability,antioxidant ability.The boron nitride materials with high specific surface has a potential application value in hydrogen storage materials,catalyst carrier,environmental protection and other fields.In recent years,scholars at home and abroad had done a large number of studies on the preparation,properties and application of boron nitride materials.How to make use of raw materials with cheap,low toxicity to get boron nitride with high specific surface area under the condition of low temperature and low pressure and make full use of its superior properties would be one of the hot issues in boron nitride materials research in the future.In this paper,we use boric acid and borax as source of boron,melamine and urea as the nitrogen source,under the condition of high temperature with nitrogen protection to get different morphology of hexagonal boron nitride.X-ray diffraction(XRD)results show that the products are hexagonal boron nitride,field emission scanning electron microscopy(SEM)and transmission electron microscopy(TEM)have carefully observed the morphology of hexagonal boron nitride.It is found that disc-like hexagonal boron nitride with high purity and better crystallization can be prepared by boric acid,borax and urea as raw materials.Fibrous hexagonal boron nitride can be prepared by boric acid and melamine as raw materials under the condition.Transmission electron microscopy(TEM)showed that there is mesoporous structure on the surface of fibrous hexagonal boron nitride.Both of the different morphology boron nitride are tested by BET,and the results show that they have different specific surface area.Under the optimum synthetic process conditions,the specific surface area of fibrous hexagonal boron nitride can reach 626.703 m2/g(STP).Due to fibrous boron nitride has a larger specific surface area and has a great effect on methylene blue dye adsorption,adsorption of methylene blue dye separation experiment was carried out,and discuss the factors affecting adsorption separation of organic dyes.Experimental results showed that fibrous hexagonal boron nitride has a good adsorption on methylene blue and has a selective adsorption of methylene blue from the mixed solution of methylene blue and copper sulfate.Molecular adsorbent and the adsorbate molecule are mainly happened between intermolecular van der Waal interactions.The innovation of this article lies in the synthesis of hexagonal boron nitride by most basic chemical raw materials under the condition of normal pressure and obtain the fibrous hexagonal boron nitride materials with high specific surface area.What is more,we have done some researches in order to explore methylene blue dye adsorption performance of hexagonal boron nitride,which lay a foundation for the development and utilization of hexagonal boron nitride materials in the future.