Size effect and enhanced photocatalytic activity of CuO sheet-like nanostructures prepared by a room temperature solution phase chemical method

Size effect and photocatalytic activity of CuO sheet-like nanostructures, which were synthesized by a facile solution phase chemical method with ethanol and water mixture as solvent, have been investigated by UV-vis absorption spectrum and photocatalytic degradation of pollutant rhodamine B (RhB). UV-vis absorption spectrum indicated that the band gap energy was about 2.31 eV for the as-prepared CuO nanostructures. The result indicates that the band gap energy of the CuO sheet-like nanostructures is much larger than value of bulk CuO crystals, showing that the CuO sheet-like nanostructures exhibit a strong quantum size confinement effect. The photocatalytic activity indicates that the as-synthesized CuO sheet-like nanostructures show an enhanced photocatalytic activity with 96.7% degradation of RhB after 9 h reaction under UV light irradiation, which was much higher than that of commercial CuO powders (39.6%).

Highlights► Size effect and photocatalytic activity of CuO sheet-like nanoparticles were studied. ► UV-vis absorption spectrum of CuO nanostructures exhibits a strong size effect. ► Photocatalytic degradation of RhB of CuO sheet-like nanostructures was evaluated. ► CuO sheet-like nanostructures show 96.7% decomposition of RhB after 9 h reaction. ► CuO nanostructures may have potential in catalysis and environmental remediation.