Self-organized TiO_2 nanotube arrays by anodization of Ti substrate: Effect of anodization time, voltage and medium composition on oxide morphology and photoelectrochemical response

摘要

This study probes the relationship between the morphology of anodic titania (TiO_2) layers grown on Ti foil substrates and their subsequent photoelectrochemical response in 0.5 M Na_2SO_4 supporting electrolyte. The effects of anodization variables (voltage and time) and anodization medium composition [water, glycerol, poly(ethylene glycol), ethylene glycol] along with fluoride ion concentration on the oxide layer of morphology and photoresponse are described. The degree of order of the self organized TiO_2 nanotube arrays and the extent to which these arrays organize themselves over the entire substrate surface are key variables dictating the corresponding quality of the resultant photoresponse.