ZnS semiconductor nanodisks are directly prepared from zinc chloride perovskite organic-inorganic layered crystals (CnH2n+1NH3)(2)ZnCl4 (n=10 and 12) by reacting their spin-casting films with H2S gas. The alkyl amine layers in the template act both for structure-direction and for surface-passivation during the formation of nanodisks. Transmission electron microscopy (TEM), UV-vis spectroscopy and small-angle X-ray diffractornetry (SAXD) are used to characterize the product morphology and the matrix structure. Quartz Crystal Microbalance (QCM) is also applied to explore the kinetics of such gas-solid reaction. Obtained results indicate an effective way to prepare functional inorganic nanoparticles from structured hybrids. (C) 2004 Published by Elsevier B.V.