Preparation of Cu2O/exfoliated graphite composites with high visible light photocatalytic performance and stability

Cu2O/exfoliated graphite composites (Cu2O/EG (1 wt%), Cu2O/EG (4 wt%), Cu2O/EG (7 wt%), Cu2O/EG (10 wt%), and Cu2O/EG (15 wt%)) were prepared by the precipitation method. The photocatalytic activity of the material was evaluated using the decolorization of methyl orange (MO) solution as model reaction. Results showed that Cu2O deposited on the worm-like flakes of EG in the form of nanocrystals. The EG provided a three-dimensional environment for photocatalytic reaction and endowed a high adsorption capacity for the sample. Under optimal conditions, the decolorization efficiencies of MO for 60 min reached 96.7%. Recycling of the catalyst showed Cu2O/EG composites (10 wt%) to possess high photocatalytic efficiency even when repeatedly used for five times.