One-Pot Room Temperature Synthesis of Cu 2 O/Ag Composite Nanospheres with Enhanced Visible-Light-Driven Photocatalytic Performance

Cu 2 O/Ag composite nanospheres (CNSs) with tunable Ag coverage and optical properties have been prepared based on a one-pot room temperature method by adding AgNO 3 solution to fresh Cu 2 O nanosphere-produced mother solution in various ratios. Ag + ions can be reduced by the primary Cu 2 O nanospheres in the acidic solution, and the obtained Ag nanoparticles can be deposited on the surfaces of the Cu 2 O nanospheres. The photocatalytic activity of Cu 2 O/Ag CNSs has been evaluated for photodegradation of methyl orange (MO) dye under visible-light irradiation, which demonstrates that Cu 2 O nanospheres with Ag loading exhibit significantly enhanced photocatalytic activity compared with pure Cu 2 O counterparts, and their photocatalytic properties depend on the coverage density of Ag nanoparticles. The enhanced photocatalytic activity can be attributed to the deposition of Ag acting as electron sinks to prevent the recombination of the photogenerated electrons and holes, and the plasmon resonances of the Ag nanoparticles generating more electron–hole pairs in the semiconductor.