Enhanced visible light photocatalysis of cuprous oxide nanoparticle modified zinc oxide nanowires

• Cu2O nanoparticle modified ZnO nanowires are grown.
• Modified ZnO nanowires have excellent visible light photocatalysis.
• Photodegradation of a 50 μM rhodamine B solution is evaluated.
• The kinetic constant of modified nanowires is 8.8 times the unmodified value.
• A degradation efficiency of 97% in 2 h is obtained by using direct sunlight.

We report on the excellent photocatalytic activity of Cu2O nanoparticle (NP) modified ZnO nanowires (NWs) in the visible light range. The NP modification is realized by photoreduction and subsequent thermal annealing in vacuum. Transmission electron microscopy analysis confirms that the NPs are in the form of Cu2O. For the degradation of a 50 μM rhodamine B solution under the illumination of a halogen lamp, the zeroth-order kinetic constant of the NP modified NWs is around 0.22 μM min−1 and 8.8 times as high as that of as-grown NWs. The achieved performance compares well with reported results of visible light photocatalysis of NP modified ZnO NWs. Furthermore, a kinetic constant of 0.53 μM min−1 and a degradation efficiency of 97% in 2 h have been obtained by using sunlight illumination.