Abstract: A proton-conductive electrochemical device and method for manufacturing the device. The device comprising a positive electrode able to reduce an oxidizing species, a negative electrode able to oxidize a reducing species, and a proton-conductive electrolyte, in contact with the positive and negative electrode. The device further comprises a layer able to diffuse protons and electrons, and forms a protective barrier against contaminants for the electrolyte. The layer is in contact with both the electrolyte and the negative electrode, and comprises a material of the type ABB?O3 or a material of the type ABO3, wherein A is an element chosen from group II of the periodic table, B is an element chosen from cerium and group IVB of the periodic table, B? is an element chosen from lanthanides or group VIIIB of the periodic table, and the layer has a porosity of less than 10% by volume.

Abstract: A proton-conductive electrochemical device. The device comprising a positive electrode able to reduce an oxidizing species, a negative electrode able to oxidize a reducing species, and a proton-conductive electrolyte, in contact with the positive electrode and the negative electrode. In addition, the device further comprises a layer able to diffuse protons and electrons, said layer forming a protective barrier against contaminants for the proton-conductive electrolyte. The layer is in contact with the proton-conductive electrolyte on the one hand and the negative electrode on the other hand. A method for manufacturing such device is also provided.