阳极氧化法制备氧化铝纳米线

将Al片在较高的电压下进行阳极氧化,制备了氧化铝纳米线。其形成机制主要是多孔氧化铝膜生长的同时,其微结构单元阵列在薄膜应力作用下沿薄壁处破裂,从而生成了氧化铝纳米线。扫描电镜和透射电镜观测表明,所得产物结构外形基本一致,呈凹柱面正三棱柱形,表观直径约30～300nm,长度为几微米至数十微米。采用BET法对产物的比表面积进行测量,实验值为5.8×104m2/kg,接近于理论计算值6.2×104m2/kg。实验表明,这种氧化铝一维纳米结构材料对超小Ag和CdS纳米颗粒具有较强的吸附能力,对很难用传统的过滤和离心沉淀法去除的超小纳米颗粒(直径小于10nm)也能做到有效吸附,有望成为超级吸附与过滤材料。

Fabrication of Alumina Nanowires via Anodic Oxidation of Aluminum

Alumina nanowires were fabricated by high voltage anodization of an aluminum sheet.The formation mechanism was discussed in detail.During the anodization procedure,the microstructure cell array split along the thinnest positions under mechanical stress existing in alumina membranes when the porous alumina membranes grew,thus the alumina nanowires were fabricated.According to the characterizations of scanning electron microscope(SEM)and transmission electron microscope(TEM),the morphologies of separated alumina nanowires are uniform triangular prism with concave and cylindrical side-faces.The alumina nanowires are 30-300 nm in diameter and several to tens of micrometers in length.The specific surface value of brunauerem-mett-teller(BET)measurement is 5.8×104 m2/kg,approximating to the theoretical value of 6.2×104 m2/kg.The experimental results show that these one-dimensional alumina nanostructures have strong absorbability to ultrafine nanoparticles of Ag and CdS.They can absorb nanoparticles(the diameter less than 10 nm)that are too small to be eliminated by conventional filters or centrifuges.Therefore,the as-prepared alumina nanowires will be useful as super absorbents or filters.