Valota A, Leclere D J, Hashimoto T, Skeldon P, Thompson G E, Berger S, Kunze J, Schmuki P
Corrosion and Protection Centre, School of Materials, The University of Manchester, PO Box 88, Manchester M60 1QD, UK.
Nanotechnology. 2008 Sep 3;19(35):355701. doi: 10.1088/0957-4484/19/35/355701. Epub 2008 Jul 18.
The formation of nanotubes on titanium is compared for anodizing under controlled voltage and controlled current in a fluoride/glycerol electrolyte. Rutherford backscattering spectroscopy and nuclear reaction analysis are employed to determine the film compositions. Film morphologies are examined by electron microscopy. The findings reveal films of approximate composition TiO(2).0.15TiF(4) that probably also contain derivatives of glycerol. Controlled voltage conditions resulted in more uniform final nanotube dimensions, for a particular charge density, and the highest efficiency of film growth, with the charge of the titanium in the film representing ∼48% of the charge passed during anodizing. Under current control, the efficiency decreased from ∼40% to ∼23% with increase of the current density from 0.1 to 0.5 mA cm(-2). Further, the thickness of the barrier layer was sometimes enhanced under current control, possibly due to a non-uniform current distribution and consequently elevated local temperature.
在氟化物/甘油电解质中，比较了在控制电压和控制电流条件下钛表面纳米管的形成情况。采用卢瑟福背散射光谱和核反应分析来确定薄膜成分。通过电子显微镜检查薄膜形态。研究结果表明，薄膜的近似组成为TiO(2).0.15TiF(4)，可能还含有甘油衍生物。对于特定的电荷密度，控制电压条件导致最终纳米管尺寸更均匀，且薄膜生长效率最高，薄膜中钛的电荷量占阳极氧化过程中通过电荷量的约48%。在电流控制下，随着电流密度从0.1 mA cm(-2)增加到0.5 mA cm(-2)，效率从约40%降至约23%。此外，在电流控制下，阻挡层的厚度有时会增加，这可能是由于电流分布不均匀以及局部温度升高所致。
