Without the assistance of any template and surfactant, In2S3 microspheres constructed with nanoflakes or nanoparticles were controllably synthesized via the hydrothermal reaction of InCl3 4H(2)O and Na2S2O3 5H(2)O in 6 25 vol.% acetic acid aqueous Solution (pH = 3)at 150-180 degrees C for 6-24 h The nanostructured In2S3 can be completely transformed into In2O3 when subjected to calcination in an at 600-700 degrees C for 5h The In2O3 produced at 600 degrees C consisted of microspheres built LIP with the nanoparticles of 20-30 nm in diameter. X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, field emission scanning electronic microscope. Raman and photoluminescence spectra have been used to characterize the structures, compositions and optical properties of the obtained products (C) 2009 Elsevier B V All rights reserved