The present study is focused on the preparation of zirconia-based coatings obtained by Electrostatic Spray Deposition (ESD). Microstructural properties of ESD coatings were optimised versus the composition of the precursor solution and the substrate nature. This chemical approach includes the influence of zirconia precursors, yttrium chloride, solvent mixtures, zirconia precursor concentration, additives and substrate nature in order to optimally tune the microstructure of the coating. A smooth, dense and homogeneous thin layer was successfully deposited. (c) 2006 Elsevier B.V. All rights reserved.