With glucose as reducing agent, Cu2O particles with different size and morphology were synthesized selectively by a seed-mediated growth approach. The major advantage of this process is that Cu(II) cannot be reduced to Cu metal. The size of the Cu2O Particles can be controlled by changing the Cu(II) concentration in colloid solution. Square-shaped Cu2O particles (20-700 run in diameter) were obtained in the presence of PEG 400, and polygonal-shaped Cu2O particles (similar to1000 nm) were observed upon using triblock copolymer as modifier, while sphere-shaped Cu2O particles with a diameter of 400-700 nm were obtained in the absence of a modifier. (C) 2003 Elsevier Science (USA). All rights reserved.