In this work, the anodization of Ti spheres using bipolar electrochemistry is reported for the first time. TiO₂ nanotubes were found over the entire surface area of the Ti spheres when a square-wave potential was employed. The TiO₂ nanotubes were ∼77 nm in inner diameter and had a thickness of ∼2 µm on the extremities of the Ti spheres. Due to their increased surface area, the Ti spheres covered with TiO₂ nanotubes had a rate constant for the photocatalytic degradation of methylene blue which was approximately 2.15 times higher than that of non-anodized Ti spheres with a thin thermal oxide layer.

中文翻译：

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双极电化学法在钛球上制备TiO ₂纳米管

在这项工作中，首次报道了使用双极电化学技术对Ti球进行阳极氧化的方法。当使用方波电势时，在Ti球的整个表面积上发现了TiO ₂纳米管。TiO ₂纳米管的内径约为77 nm，在Ti球的末端厚度约为2 µm。由于其表面积增加，被TiO ₂纳米管覆盖的Ti球具有亚甲基蓝光催化降解的速率常数，该速率常数比具有薄的热氧化物层的未阳极化Ti球的速率常数高约2.15倍。