Fabrication, Modification, and Emerging Applications of TiO₂ Nanotube Arrays by Electrochemical Synthesis: A Review

Figure 1

SEM images of TNA layers grown with different electrolytes. (a) Typical morphology obtained in acidic fluoride or HF electrolytes, (b) glycerol/fluoride electrolytes, and (c) ethylene glycol/fluoride electrolytes containing small amount of water. The insets show top views, bottom views, and side walls in detail. (d) Fluoride ions free electrolyte; these tubes grow in disordered bundles within seconds at comparably high anodic potentials. (e) Morphology of new type TNAs with time.

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