Enhanced photocatalytic activity of copper-doped ZnO nanocrystals synthesized by a hydrothermal route

Zn(1-x)CuxO (x = 0, 1, 3, 5%) nanocrystals were synthesized via a hydrothermal method at 150°C for 24 h. The structural, morphological, optical and photocatalytic properties of the samples were investigated, and found to be dependent on the content of the copper dopant. The UV photocatalytic activities of Zn(1-x)CuxO nanocrystals were evaluated by the photodecomposition of the methyl orange (MO) dye. The nanocrystals with a Cu content of 5% exhibited the highest UV photocatalytic activity with a photodegradation efficiency of 94% during 120 min as compared to that of pure ZnO with 73%. The enhancement of the photocatalytic activity of Zn0.95Cu0.05O originates from the better separation of the photogenerated electron-hole pairs.