Previously, hollow Cu2O configurations have been fabricated with the use of template or etchant. However, in this study, simply mixing aqueous sodium dodecyl sulfate (SDS), CuCl2, NaOH, and NH2OH center dot HCl in the order listed, Cu2O polyhedron with empty interior arise, which is rarely reported. Observations made on the novel particles confirm the hollow polyhedral feature and reveal that the uniform particles exhibit a narrow size distribution at around 300-400 nm in diameter and ca. 50 nm in wall thickness. It was recorded that, upon the addition of reductant (NH2OH center dot HCl), the solution color changed orderly from light blue to green, yellow, and then orange within 1 h, while the basic mixture solution turned to acid immediately. We have reason to attribute the formation of hollow polyhedron to the surfactant role of SDS and the co-etching effect of oxidative etching and acidic etching, acting on dissolving Cu2O nanocrystals via oxidation with oxygen and reaction with HCl (from NH2OH center dot HCl). (C) 2015 Elsevier B.V. All rights reserved.