In this work, a facile route using simple hydrothermal reaction and sequential calcinations to synthesize 3-dimensional flower-like Y2O3:Eu3+ nanoarchitectures without employing templates or matrix for self-assembly is presented. The flower-like nanostructures are composed of nanosheets with thickness of about 30 nm, which is verified by the field-emission electron microscopy (FESEM). Influencing factors such as the dosage of reactants, the solvent, and pH are systematically investigated. The time-dependent experiments indicate a self-assembly mechanism. This method is also applicable in the preparation of other lanthanide oxides. The PL spectra of the as-synthesized Y2O3:Eu3+ are systematically studied. Both the Eu3+ concentration and the calcinations temperature have great effect on the luminescence intensity of D-5(0)-F-7(2) transition. The decay curve of the D-5(0) transition shows that the lifetime of the as-obtained Y2O3:Eu3+ is about 2.4 ms. (C) 2007 Elsevier Inc. All rights reserved.