Photocatalytic activity of Cu2O nanoparticles prepared through novel synthesis method of precursor reduction in the presence of thiosulfate

A novel fabrication of Cu2O nanoparticles was successfully achieved through the reduction of Cu2+ in the interlayer of montmorillonite (denoted as MT). The Cu2O naroparticles formed in the clay interlayer (denoted as Cu2O/MT) had a lamellate shape of 20-100 nm in width and ca. 039 nm in thickness, and thus, the Cu2O/MT exhibited a higher specific surface area than neat Cu2O. The Cu2O/MT was applied to a photocatalyst, and its photocatalytic activity was examined in terms of water reduction (i.e., H-2 evolution) in the presence of methanol (electron donor). The Cu2O/MT showed a high photocatalytic activity in comparison with neat Cu2O; moreover, the photocatalytic activity was improved by loading a Pt catalyst onto the surface of Cu2O. Based on the dependencies of photocatalytic activity on light intensity as well as methanol concentration, it was revealed that the H-2 evolution from water on Cu2O/MT is the rate-determining step. Thus, the active and efficient photocatalysis of Cu2O/MT was associated with an increase in specific surface area corresponding to the number of active sites. (C) 2009 Elsevier Masson SAS. All rights reserved.