A fuel cell is taught comprising an anode support with an anode functional layer situated on top of and in contact with the anode support. A ScCeSZ electrolyte layer is then disposed on top of and in contact with the anode functional layer. A SDC electrolyte layer is then disposed on top of and in contact with the ScCeSZ electrolyte layer. Finally, a cathode layer is disposed on top of and in contact with the SDC electrolyte layer.

An electrode can include a functional layer having an Ln.sub.2MO.sub.4 phase, where Ln is at least one lanthanide optionally doped with a metal and M is at least one 3d transition metal, and a heavily-doped ceria phase. In an embodiment, the ceria phase can be present in the functional layer in an amount of at least 40 vol % based on a total volume of the functional layer absent any porosity. An electrochemical device or a sensor device can include the electrode.

An intermediate layer containing CeO.sub.2 with which a rare earth element (excluding Ce) forms a solid solution and a first electrode layer may be disposed in this order on a surface on one side of a solid electrolyte layer containing Zr, and a second electrode layer may be disposed on a surface on another side opposite the surface of the one side of the solid electrolyte layer. The intermediate layer includes a first layer located closer to the solid electrolyte layer and a second layer disposed on the first layer and located closer to the first electrode layer, and a concentration of the rare earth element of the first layer may be greater than a concentration of the rare earth element of the second layer.

An energy conversion device for conversion of chemical energy into electricity. The energy conversion device has a first and second electrode. A substrate is present that has a porous semiconductor or dielectric layer placed thereover. The porous semiconductor or dielectric layer can be a nano-engineered structure. A porous catalyst material is placed on at least a portion of the porous semiconductor or dielectric layer such that at least some of the porous catalyst material enters the nano-engineered structure of the porous semiconductor or dielectric layer, thereby forming an intertwining region.

Electrode-supported tubular solid-oxide electrochemical cells suitable for use in electrochemical synthesis and processes for manufacturing such are provided.

A cell stack device includes a fuel cell, a first separator and a first bonding member. The fuel cell includes a solid electrolyte and a cathode that is provided on one surface of the solid electrolyte. The first separator includes a protrusion that protrudes towards the cathode. The first bonding member bonds the cathode and the first protrusion. The thickness of a first bonding member that is positioned on an outer peripheral portion is greater than the thickness of a first bonding member that is positioned in a central portion.

An electrolyte membrane for a reformer-less fuel cell is provided. The electrolyte membrane is assembled with fuel and air manifolds to form the fuel cell. The fuel manifold receives an oxidizable fuel from a fuel supply in a gaseous, liquid, or slurry form. The air manifold receives air from an air supply. The electrolyte membrane conducts oxygen in an ionic superoxide form when the fuel cell is exposed to operating temperatures above the boiling point of water to electrochemically combine the oxygen with the fuel to produce electricity. The electrolyte membrane includes a porous electrically non-conductive substrate, an anode catalyst layer deposited along a fuel manifold side of the substrate, a cathode catalyst layer deposited along an air manifold side of the substrate, and an ionic liquid filling the substrate between the anode and cathode catalyst layers. Methods for manufacturing and operating the electrolyte membrane are also provided.

An electrochemical device can include a cathode layer including an ionic conductor material and an electronic conductor material. The cathode layer can include a ratio of (Vi/Ve) of a volume of the ionic conductor material (Vi) to a volume of the electronic conductor material (Ve) of at least 1.3. In an embodiment, the cathode layer can include a median surface diffusion length (Ls) greater than 0.33 microns. In an embodiment, the cathode layer can include a cathode functional layer.

A metal substrate for use in a metal-supported electrochemical cell is disclosed, the substrate containing a porous metal support comprising a first metal, such as a ferritic alloy, having applied on one side thereon a barrier layer comprising a bimodal distribution of micron-sized grains of a second metal, for example, nickel, and submicron-sized grains of a metal oxide, for example, gadolinium-doped ceria. A method of fabricating the metal substrate is disclosed. A metal-supported electrode and a metal-supported electrochemical cell are fabricated with the metal substrate.

Cobalt and copper-doped nickel Cu/CoNi-ferrite nanoparticles having a general formula Cu.sub.xCo.sub.xNi.sub.(1-x)Fe.sub.2O.sub.4 can be a catalyst for electrooxidation of methanol in direct methanol fuel cells (DMFC). The catalyst can be an efficient anode for DMFC in alkaline electrolytes. The Cu/CoNi-ferrite nanoparticles can have a sponge-like structure with irregular pores. A diameter of the Cu/CoNi-ferrite nanoparticles can range from about 8 nm to about 30 nm.