Fig. 4. (a) Proposed formation scheme of the Cu2O–Cu composite microspheres under the irradiation of different laser energy (10 mA, 20 mA, 30 mA); (b) photocatalytic degradation of MB in the presence of catalysts fabricated by laser-reduced reduction method and hydrothermal method, respectively; (c) typical absorbance spectra of MB dye after irradiation by 450 nm, 600 nm and full spectrum light; (d) UV-vis spectra of halogen lamp and catalysts fabricated by laser-reduced reduction method.
