Co-doped titanate nanotubes

Co-doped titanate nanotubes were synthesized through 130 °C treatment of Co-doped TiO2 powders in high concentration NaOH aqueous solutions in a hydrothermal autoclave. The obtained nanotubes were identified to be of a monoclinic layered trititanate structure, the same as H2Ti3O7, their un-doped counterpart. The incorporation of Co ions was identified by energy dispersive spectroscopy. The Ti:Co atomic ratio in the obtained nanotubes was found significantly less than the value in the powder precursor. This indicates that the precursor powders were deformed in NaOH solution before the formation of nanotubes. Magnetic measurement showed a hysteresis loop at room temperature.