The invention concerns a method for preparing a thin ceramic material with controlled surface porosity gradient, including (A) infiltrating a porous pore-forming substrate of controlled thickness, with a ceramic material suspension; (B) evaporating the solvent; (C) a step which includes eliminating the pore-forming agents and the various organic additives, and (D) a sintering step. The invention also concerns the use of the ceramic material in the method for preparing a solid electrolyte and a mixed ionic-electronic conductor, in methods for preparing ultra-pure oxygen, for eliminating oxygen from a gaseous atmosphere, for producing heat energy, for preparing gas or liquid filtering membranes, for ceramic/metal joints, for biomaterials and sensors.