This paper concerns the microstructure of the anodic titanium oxide ͑ATO, TiO 2 ͒ nanotube ͑NT͒ and its use for the dye-sensitized solar cell ͑DSSC͒ device. The ATO length was controlled by various electrolytes and anodic time at various constant applied voltages. The lengths of the NTs at 0.3-0.5 and 0.9-22 m were controlled by 0.5 vol % HF and 0.58 wt % KF aqueous solutions for varied periods of anodization ͑1-24 h͒. The 0.5 wt % NH 4 F electrolyte in ethylene glycol can produce 4-41 m for varied periods of anodization ͑0.5-8 h͒. ATO made of 0.3 ͑0.5 vol % HF͒, 12 ͑0.5 wt % KF͒, and 18 m ͑0.5 wt % NH 4 F͒ was used for the DSSC anode; the best cell performance attained 0.13, 3.76, and 6.18%. The DSSC made of 18 m ATO has a short-circuit current density ͑J sc ͒ of 13.45 mA/cm 2 , a fill factor of 0.64, an open voltage ͑V oc ͒ of 0.72 V, and a photocurrent efficiency of 6.18% under an air mass 1.5 illumination test.

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