一步法制备BN/Si复合团簇结构

Synthesis of Composite Clusters of BN/Si by One Step Route

以球磨的B/BN混合物为原料,采用一步法在蘸有催化剂的硅片上合成了大量BN纳米刺包裹在Si纳米或微米线上的复合团簇结构。EDS和SAED表明外层的纳米刺是六方BN多晶,里面包裹的Si纳米或微米线则是立方的Si单晶。实验结果表明合成温度对BN/Si复合结构形成有重要影响,只有在1250℃以上的温度才会生成BN/Si复合团簇结构,另外只有当硅片与样品接触时才会形成复合产物。PL光谱显示复合产物在360 nm的激发下,其发光峰在303 nm(4.1 eV)和423 nm(2.93 eV)处。

Using ball-milled B/BN mixture powders as raw materials,BN sheathing layers stacked by thorn-like nanostructures on silicon nanowires or micronwires were synthesized on the iron-deposited silicon substrate by one-step route.The as-synthesized products grew self-assembled forming the microsize clusters of BN/Si.The results of EDS and SAED indentified that the nanowires or micronwires inside were cubic Si with single crystalline structure and the outer layers were hexagonal BN with polycrystalline structure.Experiments showed that the composite clusters of the BN /Si were able to grow only above 1250 ℃.The position of Si substrate was also an important factor for the formation of BN/Si product.If the sample didn＇ t contact on the Si substrate,no BN/Si products formed.The photoluminescence（PL） spectrum showed two emissions peaks at 303 nm（4.1 eV）and 423 nm（2.93 eV） exsit under excitation at 360 nm.