Self-Ordered Anodic Aluminum Oxide Formed by H2SO4 Hard Anodization
Citations Over TimeTop 10% of 2008 papers
Abstract
The self-ordering of nanoporous anodic aluminum oxide (AAO) in the course of the hard anodization (HA) of aluminum in sulfuric acid (H2SO4) solutions at anodization voltages ranging from 27 to 80 V was investigated. Direct H2SO4-HA yielded AAOs with hexagonal pore arrays having interpore distances Dint ranging from 72 to 145 nm. However, the AAOs were mechanically unstable and cracks formed along the cell boundaries. Therefore, we modified the anodization procedure previously employed for oxalic acid HA (H2C2O4-HA) to suppress the development of cracks and to fabricate mechanically robust AAO films with Dint values ranging from 78 to 114 nm. Image analyses based on scanning electron micrographs revealed that at a given anodization voltage the self-ordering of nanopores as well as Dint depend on the current density (i.e., the electric field strength at the bottoms of the pores). Moreover, periodic oscillations of the pore diameter formed at anodization voltages in the range from 27 to 32 V, which are reminiscent of structures originating from the spontaneous growth of periodic fluctuations, such as topologies resulting from Rayleigh instabilities.
Related Papers
- → Self-ordering of anodic nanoporous alumina fabricated by accelerated mild anodization method(2010)26 cited
- → Mechanisms of Nanoporous Alumina Formation and Self-organized Growth(2015)11 cited
- → Effects of anodization conditions of stainless steel on the formation of ordered nanoporous structures with high aspect ratios(2023)7 cited
- → Formation of spinel CoFe2O4 nanoporous oxide layers by electrochemical anodization(2021)2 cited
- → Rapid and tunable growth of a well-ordered hexagonal nanoporous anodic aluminum oxide (AAO) structure by two-step high-temperature anodization(2021)