Apolinário Arlete, Sousa Célia T, Oliveira Gonçalo N P, Lopes Armandina M L, Ventura João, Andrade Luísa, Mendes Adélio, Araújo João P
Instituto de Física de Materiais Avançados, Nanotecnologia e Fotónica (IFIMUP), Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Rua do Campo Alegre, 678, 4169-007 Porto, Portugal.
Laboratory for Process Engineering, Environment, Biotechnology and Energy (LEPABE), Departamento de Engenharia Química, Faculdade de Engenharia, Universidade do Porto, R. Dr. Roberto Frias, 4200-465 Porto, Portugal.
Nanomaterials (Basel). 2020 Feb 22;10(2):382. doi: 10.3390/nano10020382.
Highly ordered anodic hafnium oxide (AHO) nanoporous or nanotubes were synthesized by electrochemical anodization of Hf foils. The growth of self-ordered AHO was investigated by optimizing a key electrochemical anodization parameter, the solvent-based electrolyte using: Ethylene glycol, dimethyl sulfoxide, formamide and N-methylformamide organic solvents. The electrolyte solvent is here shown to highly affect the morphological properties of the AHO, namely the self-ordering, growth rate and length. As a result, AHO nanoporous and nanotubes arrays were obtained, as well as other different shapes and morphologies, such as nanoneedles, nanoflakes and nanowires-agglomerations. The intrinsic chemical-physical properties of the electrolyte solvents (solvent type, dielectric constant and viscosity) are at the base of the properties that mainly affect the AHO morphology shape, growth rate, final thickness and porosity, for the same anodization voltage and time. We found that the interplay between the dielectric and viscosity constants of the solvent electrolyte is able to tailor the anodic oxide growth from continuous-to-nanoporous-to-nanotubes.
通过对铪箔进行电化学阳极氧化合成了高度有序的阳极氧化铪（AHO）纳米多孔结构或纳米管。通过优化关键的电化学阳极氧化参数——使用基于溶剂的电解质（乙二醇、二甲基亚砜、甲酰胺和N - 甲基甲酰胺等有机溶剂），研究了自有序AHO的生长情况。结果表明，电解质溶剂对AHO的形态特性有很大影响，即自有序性、生长速率和长度。由此获得了AHO纳米多孔和纳米管阵列，以及其他不同的形状和形态，如纳米针、纳米薄片和纳米线团聚体。在相同的阳极氧化电压和时间下，电解质溶剂的固有化学物理性质（溶剂类型、介电常数和粘度）是主要影响AHO形态形状、生长速率、最终厚度和孔隙率的性质的基础。我们发现，溶剂电解质的介电常数和粘度常数之间的相互作用能够将阳极氧化物的生长从连续结构调整为纳米多孔结构再到纳米管结构。
