The Controllable Preparation,Propeties And Applications Research Of Few- Layer Boron Nitride Hollow Nanostructures

Hexagonal boron nitride (h-BN) have a wide range of attractive properties, including high temperature stability, a low dielectric constant, high mechanical strength, a large thermal conductivity, high hardness, and high corrosion resistance, leading to a number of potential applications. Hexagonal boron nitride has a two dimensional strong sp2 covalent bond-containing honeycomb structure that is similar to that of graphene, which make it has high mechanical strength and thermal conductivity, can be used as an additive to improve mechanical properties and thermal properties of the polymer film material. However, graphene exhibits semimetallic properties and has a zero band gap, while h-BN is an insulator with a direct band gap of 5-6 eV. This is attributable to the partially ionic character of the B-N bonds.Highly purified h-BN exhibits intense excitonic luminescence bands for wavelengths ranging from 215 to 227 nm, which are sufficiently strong to cause stimulated emission. Therefore, high-quality h-BN is a promising material for deep UV optoelectronic devices. h-BN also shows great potential in high-performance electronic devices. In recent years, graphene, one monolayer of graphite, has been considered to be an ideal material for the fabrication of nanoelectronic devices due to its excellent electrical properties.It was suggested that due to the close match of the lattice parameters between h-BN and graphene, epitaxial graphene on h-BN would give rise to a band gap opening of graphene, and potentially h-BN can also serve as a good gate dielectric for graphene transistors. Have excellent chemical stability, adsorption properties and good biocompatibility, it can be used as energy storage materials, adsorption materials, template material and drug deliverWith the development of the carbon material, BN material with various morphologies were prepared.The discovery of graphene raised the interest of preparing atomically thin boron nitride nanomaterials. However, due to the characteristics of boron nitride material itself, BN material were often obtained in extremely harsh conditions, tedious process and other issues. The graphene can be obtained by oxidation reduction and exfoliation,but these methods can not be used to preparing atomically thin boron nitride because of its high oxidation resistance and strong interaction between layers. Developing We have developed a one-step reaction under mild conditions prepared boron nitride material, and as the nature of basic research and application of boron nitride material.1^ We prepared boron nitride hollow spheres with a facile template-free solid state synthesis route. In this reaction, the ratio of the reaction volume and the amount of starting materials determine on the morphology and quality of boron nitride sample. Finally, at about 300℃, a high purity, uniform morphology boron nitride hollow spheres were obtained in 100ml autoclave. Further Study on the adsorption, we controlling the pH change to achieve a certain selective adsorption by using the difference of maximum adsorption between positive and negative organic dyes ions. Finally by using partially hydrolyzed assisted exfoliation method in a mixed solvent of water and DMF, atomically thin shells of boron nitride hollow spheres are local present.2、Atomically thin boron nitride (BN) hollow nanospheres were directly synthesized via a modified CVD method followed by subsequent high-temperature degassing treatment. The encapsulated impurities in the hollow nanospheres were effectively removed during the reaction process. The BN shells of most nanospheres consisted of 2-6 atomic layers. Because of the low thickness, the obtained BN hollow nanospheres presented excellent performance in many aspects. For instance, they were demonstrated as useful nanocontainers for controllable multistep release of iodine, which could diffuse and be encapsulated into the few-layer BN hollow nanospheres when heating. They were also promising support materials that could markedly increase the photocatalytic activity of TiO2 nanocrystals.3、We obtained few-layer (～3nm) fluorinated hexagonal boron nitride (F-BN) nanocages with zigzag-edge triangular antidot defects were synthesized via a facile one-step solid-state reaction. They are free of metallic impurities confirmed by X-ray photoelectron spectroscopy, electron energy loss spectroscopy, and inductively coupled plasma atomic emission spectroscopy. Ferromagnetism is obviously observed in the BN nanocages. Saturation magnetization values of them differed by less than 7% between 5 and 300 K, indicating that the Curie temperature (Tc) was much higher than 300 K. By adjusting the concentration of triangular antidot defects and fluorine dopants, the ferromagnetic performance of BN nanocages could be effectively varied, indicating that the observed magnetism originates from triangular antidot defects and fluorination. The corresponding theoretical calculation shows that antidot defects and fluorine doping in BN lattice both favor spontaneous spin polarization and the formation of local magnetic moment, which should be responsible for long-range magnetic ordering in the sp material.4、We prepared MoS2 nanoflowers by a hydrothermal process. The boron nitride hollow spheres were used to be a self-corrosion template to provide a substrate for the growing of the curve MoS2 sheets, and the MoS2 nanosheets self-assemble along the interface between boron nitride and solution.