Cuprous oxide and related materials in nanosizes are of much interest and investigated
extensively recently. It is reported here that cubic Cu2O nanocubes were synthesized successfully in
aqueous solutions at room temperature in air condition. Copper (II) salts in water were reduced with
ascorbate acid in air, using the nonionic pluronic amphiphilic triblock copolymer EO20PO70EO20
(P123) as the template-directing and protecting agent. The average edge length of the cubes varied
from 50 to 100 nm. Transmission electron microscopy (TEM) has been used for the shape and
structural characterization of the obtained Cu2O nanocubes. The UV-Vis spectra showed an obvious
blue-shift (0.53 eV), compared to the band gap of the bulk Cu2O crystal, which makes it a
promising candidate in solar energy conversion since this sample can make use of higher energy
visible rays of solar spectrum. In the FT-IR spectra the peak of Cu-O bond for the Cu2O is clearly
distinguished and several weak peaks of the C-H, C-C and C=O bonds for the organic species can
also be detectable, implying a little P123 residua in the products. The effect of the triblock
copolymer P123 on the growth of the Cu2O nanocubes is discussed.
