Inorganic-organic composite films containing the mixed-addenda heteropolytungsto-molybdate K10H3[Eu(SiMo9W2O39)(2)] center dot xH(2)O (abbreviated as EuSiMo9W2) and tris(2,2'-bipyridine)ruthenium(II) Ru(bpy)(3)(2+)(abbreviated as Ru(bpy)(3)) were fabricated by the layer-by-layer self-assembly method. UV-vis spectroscopy shows that the absorbance values at characteristic peaks increase linearly with the number of EuSiMo9W2/Ru(bpy)(3) bilayers, suggesting that the deposition process is linear and highly reproducible from layer to layer. The composition of the multilayer film was measured by X-ray photoelectron spectra. Atomic force microscopy presented a correspondingly uniform surface morphology and a homogeneity of the multilayer films. The film exhibited photoluminescence arising from the d-pi* metal-to-ligand transition of Ru2+, and D-5(0) metastable state to terminate levels in the F-7(J) (J = 0-4) ground-state multiplet transitions of Eu3+. The film also exhibited catalytic activities toward the reduction of IO3-, H2O2, BrO3, NO2 and the oxidation of C2O4. It may provide a novel material as bifunctional electrocatalysts and fluorescence probes in biochemistry, luminescence sensors, electroluminescent optical devices, and so on. (c) 2007 Elsevier Inc. All rights reserved.