Enhanced photoelectrochemical performance of NiO-doped TiO₂ nanotubes prepared by an impregnation–calcination method

To improve the photocatalytic activity of TiO 2 , a series NiO–TiO nanotubes (NTbs) is prepared by impregnating in solution NiCl ·6H O at different concentrations. Self-organized are two-step anodization process. Scanning electron microscopy images show that large particle agglomerates formed for higher precursor concentrations, and X-ray energy-dispersive spectroscopy results indicate atomic percentages Ni NTbs with concentrations 100 300 mM 1.95% 4.23%, respectively. Electronic lifetime measurements recombination rate photogenerated electron–hole pairs lower compared to . Specifically, sample 50 lowest, which associated longest lifetime. Compared unmodified nanotubes, exhibit improved degradation rhodamine B.