Controllable synthesis of Cu2O hierarchical nanoclusters with high photocatalytic activity

Abstract

Cu₂O nanocrystals with different morphologies and sizes were controllably synthesized by simply adjusting the reaction temperature and duration. The results suggested that Cu₂O nanocrystals obtained at 120 °C were hierarchical nanoclusters (NCs) with an average size of 25 nm and the NCs were made up of many ultrafine grains with the sizes of 2–7 nm. Such a structure facilitated the generation and transfer of carriers, leading to a high visible-light photocatalytic activity. Further analysis indicated that the Cu₂O nanocrystals with smaller size exhibited much better photocatalytic activities in degrading methyl orange (MO) under visible-light irradiation. The best result appeared in the NCs of 25 nm, which could degrade the MO solution (100 ml, 10 mg L⁻¹) completely in 12 minutes with a dosage of 10 mg. That work provides a good method for enhancing the photocatalytic activity of Cu₂O and other photocatalysts.