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Morphological instability leading to formation of porous anodic oxide films

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Abstract

Electrochemical oxidation of metals, in solutions where the oxide is somewhat soluble, produces anodic oxides with highly regular arrangements of pores. Although porous aluminium and titanium oxides have found extensive use in functional nanostructures, pore initiation and self-ordering are not yet understood. Here we present an analysis that examines the roles of oxide dissolution and ionic conduction in the morphological stability of anodic films. We show that patterns of pores with a minimum spacing are possible only within a narrow range of the oxide formation efficiency (the fraction of oxidized metal atoms retained in the film), which should exist when the metal ion charge exceeds two. Experimentally measured efficiencies, over diverse anodizing conditions on both aluminium and titanium, lie within the different ranges predicted for each metal. On the basis of these results, the relationship between dissolution chemistry and the conditions for pore initiation can now be understood in quantitative terms.

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Figure 1: Morphological instability during growth of anodic Al2O3.
Figure 2: Effect of oxide formation efficiency on dispersion curves for growth of anodic Al2O3.
Figure 3: Comparison of measured oxide formation efficiencies with predicted limits.

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Change history

  • 09 December 2011

    In the version of this Article originally published online, the term Auger electron spectroscopy was incorrectly used; it should have read atomic emission spectroscopy. This error has been corrected in all versions of the Article.

References

  1. Masuda, H. & Fukuda, K. Ordered metal nanohole arrays made by a two-step replication of honeycomb structures of anodic alumina. Science 268, 1466–1468 (1995).

    Article  CAS  Google Scholar 

  2. Li, A. P., Müller, F., Birner, A., Nielsch, K. & Gösele, U. Hexagonal pore arrays with a 50–420 nm interpore distance formed by self-organization in anodic alumina. J. Appl. Phys. 84, 6023–6026 (1998).

    Article  CAS  Google Scholar 

  3. Macak, J. M., Tsuchiya, H. & Schmuki, P. High-aspect-ratio TiO2 nanotubes by anodization of titanium. Angew. Chem. Int. Ed. 44, 2100–2102 (2005).

    Article  CAS  Google Scholar 

  4. Macak, J. M., Tsuchiya, H., Taveira, L., Aldabergerova, S. & Schmuki, P. Smooth anodic TiO2 nanotubes. Angew. Chem. Int. Ed. 44, 7463–7465 (2005).

    Article  CAS  Google Scholar 

  5. Roy, P., Berger, S. & Schmuki, P. TiO2 nanotubes: Synthesis and applications. Angew. Chem. Int. Ed. 50, 2904–2939 (2011).

    Article  CAS  Google Scholar 

  6. Skeldon, P., Thompson, G. E., Garcia-Vergara, S. J., Iglesias-Rubianes, L. & Blanco-Pinzon, C. E. A tracer study of porous anodic alumina. Electrochem. Solid-State Lett. 9, B47–B51 (2006).

    Article  CAS  Google Scholar 

  7. Mercier, D., Van Overmeere, Q., Santoro, R. & Proost, J. In-situ optical emission spectrometry during galvanostatic aluminum anodizing. Electrochim. Acta 56, 1329–1336 (2011).

    Article  CAS  Google Scholar 

  8. Li, F. Y., Zhang, L. & Metzger, R. M. On the growth of highly ordered pores in anodized aluminum oxide. Chem. Mater. 10, 2470–2480 (1998).

    Article  CAS  Google Scholar 

  9. Van Overmeere, Q., Nysten, B. & Proost, J. In situ detection of porosity initiation during aluminum thin film anodizing. Appl. Phys. Lett. 94, 074103 (2009).

    Article  Google Scholar 

  10. Baron-Wiechec, A. et al. 18O tracer study of porous film growth on aluminum in phosphoric acid. J. Electrochem. Soc. 157, C399–C407 (2010).

    Article  CAS  Google Scholar 

  11. Parkhutik, V. P. & Shershulsky, V. I. Theoretical modeling of porous oxide-growth on aluminum. J. Phys. D 25, 1258–1263 (1992).

    Article  CAS  Google Scholar 

  12. Thamida, S. K. & Chang, H. C. Nanoscale pore formation dynamics during aluminum anodization. Chaos 12, 240–251 (2002).

    Article  CAS  Google Scholar 

  13. Singh, G. K., Golovin, A. A. & Aranson, I. S. Formation of self-organized nanoscale porous structures in anodic aluminum oxide. Phys. Rev. B 73, 205422 (2006).

    Article  Google Scholar 

  14. Sample, C. & Golovin, A. A. Formation of porous metal oxides in the anodization process. Phys. Rev. E 74, 041606 (2006).

    Article  CAS  Google Scholar 

  15. Sheintuch, M. & Smagina, Y. Nanopore formation dynamics during aluminum anodization. Physica D 226, 95–105 (2007).

    Article  CAS  Google Scholar 

  16. Stanton, L. G. & Golovin, A. A. Effect of ion migration on the self-assembly of porous nanostructures in anodic oxides. Phys. Rev. B 79, 035414 (2009).

    Article  Google Scholar 

  17. Houser, J. E. & Hebert, K. R. Modeling the potential distribution in porous anodic alumina films during steady-state growth. J. Electrochem. Soc. 153, B566–B573 (2006).

    Article  CAS  Google Scholar 

  18. Houser, J. E. & Hebert, K. R. The role of viscous flow of oxide in the growth of self-ordered porous anodic alumina films. Nature Mater. 8, 415–420 (2009).

    Article  CAS  Google Scholar 

  19. Lohrengel, M. M. Thin anodic oxide layers on aluminium and other valve metals: High-field regime. Mater. Sci. Eng. R11, 243–294 (1993).

    Article  CAS  Google Scholar 

  20. Hebert, K. R. & Houser, J. E. A model for coupled electrical migration and stress-driven transport in anodic oxide films. J. Electrochem. Soc. 156, C275–C281 (2009).

    Article  CAS  Google Scholar 

  21. Oh, J. & Thompson, C. V. The role of electric field in pore formation during aluminum anodization. Electrochim. Acta 56, 4044–4051 (2011).

    Article  CAS  Google Scholar 

  22. Oh, J. & Thompson, C. V. Abnormal anodic aluminum oxide formation in confined structures for lateral pore arrays. J. Electrochem. Soc. 158, C71–C75 (2011).

    Article  CAS  Google Scholar 

  23. Van Overmeere, Q., Blaffart, F. & Proost, J. What controls the pore spacing in porous anodic oxides? Electrochem. Commun. 12, 1174–1176 (2010).

    Article  Google Scholar 

  24. Van Overmeere, Q., Vanhumbeeck, J. F. & Proost, J. Effect of current density on the internal stress evolution during galvanostatic Ti thin film anodizing. J. Electrochem. Soc. 157, C166–C173 (2010).

    Article  Google Scholar 

  25. LeClere, D. J. et al. Tracer investigation of pore formation in anodic titania. J. Electrochem. Soc. 155, C487–C494 (2008).

    Article  CAS  Google Scholar 

  26. Ebihara, K., Takahashi, H. & Nagayama, M. Interpretation of the voltage-current characteristics observed when anodizing aluminum in acid solutions. Kinzoku Hyomen Gijutsu 35, 205–209 (1984).

    CAS  Google Scholar 

  27. Macak, J. M. et al. TiO2 nanotubes: Self-organized electrochemical formation, properties and applications. Curr. Opin. Solid State Mater. Sci. 11, 3–18 (2007).

    Article  CAS  Google Scholar 

  28. Nagayama, M. & Tamura, K. Dissolution of anodic oxide film on aluminium in a sulphuric acid solution. Electrochim. Acta 12, 1097–1107 (1967).

    Article  CAS  Google Scholar 

  29. Garcia-Vergara, S. J., Skeldon, P., Thompson, G. E. & Habakaki, H. Pore development in anodic alumina in sulphuric acid and borax electrolytes. Corros. Sci. 49, 3696–3704 (2007).

    Article  CAS  Google Scholar 

  30. Berger, S. et al. A lithographic approach to determine volume expansion factors during anodization: Using the example of initiation and growth of TiO2-nanotubes. Electrochim. Acta 54, 5942–5948 (2009).

    Article  CAS  Google Scholar 

  31. Albu, S. P., Roy, P., Virtanen, S. & Schmuki, P. Self-organized TiO2 nanotube arrays: Critical effects on morphology and growth. Isr. J. Chem. 50, 453–467 (2010).

    Article  CAS  Google Scholar 

  32. Garcia-Vergara, S. J., Skeldon, P., Thompson, G. E. & Habazaki, H. A tracer investigation of chromic acid anodizing of aluminium. Surf. Interface Anal. 39, 860–864 (2007).

    Article  CAS  Google Scholar 

  33. Thompson, G. E., Skeldon, P., Shimizu, K. & Wood, G. C. The compositions of barrier-type anodic films formed on aluminum in molybdate and tungstate electrolytes. Phil. Trans. R. Soc. A. 350, 143–168 (1995).

    Article  CAS  Google Scholar 

  34. Dell’Oca, C. J. & Fleming, P. J. Initial stages of oxide-growth and pore initiation in the porous anodization of aluminum. J. Electrochem. Soc. 123, 1487–1493 (1976).

    Article  Google Scholar 

  35. O’Sullivan, J. P. & Wood, G. C. Morphology and mechanism of formation of porous anodic films on aluminium. Proc. R. Soc. Lond. A 317, 511–543 (1970).

    Article  Google Scholar 

  36. Jessensky, O., Müller, F. & Gösele, U. Self-organized formation of hexagonal pore arrays in anodic alumina. Appl. Phys. Lett. 72, 1173–1175 (1998).

    Article  CAS  Google Scholar 

  37. Barkey, D. & McHugh, J. Pattern formation in anodic aluminum oxide growth by flow instability and dynamic restabilization. J. Electrochem. Soc. 157, C388–C391 (2010).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

This research was supported financially by the National Science Foundation (CMMI-100748) and the Deutsche Forschungsgemeinschaft (including DFG cluster of excellence EAM). We thank W. Hong (Iowa State University) for helpful discussions.

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Contributions

K.R.H. carried out linear stability analysis and project planning. S.P.A. and I.P. made measurements of oxide formation efficiency during growth of anodic titania nanotube layers. P.S. contributed to the planning and analysis of these experiments.

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Correspondence to Kurt R. Hebert.

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The authors declare no competing financial interests.

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Hebert, K., Albu, S., Paramasivam, I. et al. Morphological instability leading to formation of porous anodic oxide films. Nature Mater 11, 162–166 (2012). https://doi.org/10.1038/nmat3185

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