New hybrid membranes for metal ion transport were synthesized with the aim of improving mechanical and chemical stabilities, mean lifetime and loss of carrier, Hybrid organic-inorganic materials present several advantages with respect to organic and inorganic materials considered independently. Organic-matrix membranes usually have limitations related to chemical and thermal stabilities while organosilicone materials may present serious difficulties for film formation. The new membranes proposed here are based on a mixture of organic (cellulose triacetate, CTA) and organosilicone materials (dichlorodimethylsilane and tetraethoxysilane, DDMS and TEOS, respectively) as membrane support. Membrane preparation was optimized varying the amount of metal carrier (bis(2-ethyl hexyl phosphoric acid), D2EHPA) and plasticizer (2-nitrophenyloctyl ether, NPOE and/or tris(2-butoxyethyl)phosphate), TBEP). Total Reflection Infrared Spectroscopy, Scanning Electron Microscopy, Thermogravimetric Analysis, Si-29 Nuclear Magnetic Resonance and X-Ray Diffraction were used to characterize the hybrid membranes and to correlate structural properties with permeability values for zinc metal ions. (c) 2006 Elsevier B.V. All rights reserved.