Abstract
Co 3-x Cu x O 4 nanorods with a crystalline structure were synthesized via a solution process in this study. The Co 3-x Cu x O 4 nanorods exhibit dual direct bandgaps and could be adjusted to 1.3-1.5 eV, and 2.55-3.5 eV by using different Cu-doping concentrations. The Co 3-x Cu x O 4 nanorods show an absorption coefficient of ∼10 4 cm -1 which increases with the increase of the Cu doping concentration. © 2014 the Partner Organisations.