Journal of The Electrochemical Society, 158 (12) C410-C415 (2011)
Conclusion
C415
In summary, the following conclusions can be drawn on the thermal
driving fast fabrication of PAAs:
(a)
1
2
3
.
.
.
TDA process can be easily realized by increasing the electrolyte
◦
temperature to the range of 30–70 C. In both oxalic acid and
◦
phosphoric acid, electrolyte temperature of 30 to 50 C is recom-
mended considering both the surface morphology of PAA and
feasibility of fabrication.
The growth rate is obviously increased at TDA process. In the
◦
oxalic acid, the growth rates under 30 and 50 C can be enhanced
to be 15 to 90 μm/h, respectively. In phosphoric acid, the growth
◦
rate of 1 μm/h at 0 C can be improved to be 26.4 and 37.0 μm/h
◦
at 30 and 50 C, respectively.
(
b)
The electrolyte’s erosion on the oxide layer is un-neglectable
during the TDA process in oxalic acid, which can be confirmed
by the formation of nanowires and funnel-like nanopores. The
electrolyte’s erosion on the PAA in phosphoric acid electrolyte
seems to be slow since the nanopores are intact after 30 minutes’
1
2
4
3
4
5
6
1
0 μm
◦
anodization under 60 C.
◦
4.
The TDA process in phosphoric acid under 50–70 C brings
unique microstructures, such as serrated, branched, micro-nano
combined and periodic nanpores. These innovative nanochan-
nels may pave the way for PAAs’ new applications.
(
c)
3
5
5
μm
Acknowledgments
This work was supported by Qing Lan Project (2008–04), Jiangsu
333” Project (201041) the Priority Academic Program Development
“
◦
Figure 7. (a) The current-time curve of the anodization under 150 V 70 C in
phosphoric acid, (b) and (c) the cross-sectional FESEM images of the obtained
PAA.
of Jiangsu Higher Education Institutions and Changzhou Science and
Technology project (CE20100047).
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◦
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