Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea.
Nanotechnology. 2013 May 10;24(18):185601. doi: 10.1088/0957-4484/24/18/185601. Epub 2013 Apr 11.
We present a simple and novel strategy to synthesize TiO2 nanoparticles (NPs) based on electrochemical anodization of a Ti wire in an aqueous KCl electrolyte. The Ti wire is very rapidly and directly converted to TiO2 NPs by the anodization process, allowing mass production of TiO2 NPs. The size of the synthesized NPs can be readily tuned by changing the concentration of the electrolyte. We found that the field-assisted etching related to a strong electric field and the rapid etching rate caused by chloride ions play important roles for the formation of TiO2 NPs. This approach can also be applied to the mass production of other semiconducting metal oxide NPs such as tungsten-oxide NPs. TiO2 NPs showed higher photocatalytic activity compared to Degussa (P 25) under the same conditions. The higher photocatalytic activity of TiO2 NPs is attributed to the polymorphism. We believe that our approach can be used in broad areas including biomedical applications, photovoltaics, optics, and electronics.
我们提出了一种简单新颖的策略，通过在含有 KCl 的水溶液中对钛丝进行电化学阳极氧化，来合成 TiO2 纳米颗粒（NPs）。在阳极氧化过程中，钛丝被迅速直接转化为 TiO2 NPs，从而可以大规模生产 TiO2 NPs。通过改变电解液的浓度，很容易调节合成 NPs 的尺寸。我们发现，与强电场相关的场辅助刻蚀以及氯离子引起的快速刻蚀速率对于 TiO2 NPs 的形成起着重要作用。这种方法还可以应用于其他半导体金属氧化物 NPs（如氧化钨 NPs）的大规模生产。在相同条件下，与 Degussa（P25）相比，TiO2 NPs 表现出更高的光催化活性。TiO2 NPs 具有更高的光催化活性归因于其多晶型性。我们相信，我们的方法可以应用于包括生物医学应用、光伏、光学和电子学等广泛领域。
