A process for direct compression of hydrogen separated from a hydrocarbon source is described herein. The process comprises a first zone wherein a hydrocarbon reaction that produce hydrogen occurs, a ceramic proton conductor which under an applied electric field transport hydrogen from said first zone to said second zone, and a second zone where compressed hydrogen is produced. The heat energy generated by ohmic resistance in the membrane is partially recuperated as chemical energy in the hydrocarbon reforming process to generate hydrogen.

The oxygen evolution reaction (OER) system includes a bismuth strontium cobalt oxide.

Provided are an oxidation catalyst for anion exchange membrane water electrolysis exhibiting excellent catalytic activity and electrical conductivity, a uniform particle size distribution and a large surface area, and excellent durability, and a preparation method thereof, an anode for anion exchange membrane water electrolysis and an anion exchange membrane water electrolysis system, each including the oxidation catalyst.

A perovskite-type oxide catalyst for water-splitting reactions is provided. The catalyst, Ca.sub.2-ySr.sub.yFe.sub.1-xCo.sub.1-xMn.sub.2xO.sub.6- where y=0.10-1.90 and x=0.05-0.95, has catalytic activity for both hydrogen- and oxygen-evolution reactions. An exemplary catalyst is CaSrFe.sub.0.75Co.sub.0.75Mn.sub.0.5O.sub.6-.

The present invention provides an electrode for electrolysis in which electrolysis performance is hard to deteriorate and excellent catalytic activity is kept stable over a long period of time even when electric power in which there is a large fluctuation in output, such as renewable energy, is used as a power source. The electrode for electrolysis is an electrode 10 for electrolysis provided with an electrically conductive substrate 2 at least the surface of which contains nickel or a nickel-based alloy, an intermediate layer 4 formed on the surface of the electrically conductive substrate 2 and containing a lithium-containing nickel oxide represented by composition formula Li.sub.xNi.sub.2-xO.sub.2 (0.02x0.5), and a catalyst layer 6 of a nickel cobalt spinel oxide, an iridium oxide, or the like, the catalyst layer 6 formed on the surface of the intermediate layer 4.

The present invention provides an electrode for electrolysis in which electrolysis performance is hard to deteriorate and excellent catalytic activity is kept stable over a long period of time even when electric power in which there is a large fluctuation in output, such as renewable energy, is used as a power source. The electrode for electrolysis is an electrode 10 for electrolysis provided with an electrically conductive substrate 2 at least the surface of which contains nickel or a nickel-based alloy, an intermediate layer 4 formed on the surface of the electrically conductive substrate 2 and containing a lithium-containing nickel oxide represented by composition formula Li.sub.xNi.sub.2-xO.sub.2 (0.02x0.5), and a catalyst layer 6 of a nickel cobalt spinel oxide, an iridium oxide, or the like, the catalyst layer 6 formed on the surface of the intermediate layer 4.

A CaTiO.sub.3TiO.sub.2 composite electrode and method of making is described. The composite electrode comprises a substrate with an average 2-12 m thick layer of CaTiO.sub.3TiO.sub.2 composite particles having average diameters of 0.2-2.2 m. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a calcium complex, and a titanium complex. The CaTiO.sub.3TiO.sub.2 composite electrode is capable of being used in a photoelectrochemical cell for water splitting.

Disclosed herein are doped perovskite oxides. The doped perovskite oxides may be used as a cathode material in an electrochemical cell to electrochemically generate ammonia from N.sub.2. The doped perovskite oxides may be combined with nitride compounds, for instance iron nitride, to further increase the efficiency of the ammonia production.

A method of carbon dioxide hydrogenation comprises introducing gaseous water to a positive electrode of an electrolysis cell comprising the positive electrode, a negative electrode, and a proton-conducting membrane between the positive electrode and the negative electrode. The proton-conducting membrane comprises an electrolyte material having an ionic conductivity greater than or equal to about 102 S/cm at one or more temperatures within a range of from about 150 C. to about 650 C. Carbon dioxide is introduced to the negative electrode of the electrolysis cell. A potential difference is applied between the positive electrode and the negative electrode of the electrolysis cell to generate hydrogen ions from the gaseous water that diffuse through the proton-conducting membrane and hydrogenate the carbon dioxide at the negative electrode. A carbon dioxide hydrogenation system is also described.

Disclosed is a biphasic electrically conductive perovskite-based mixed oxide of the structure ABO.sub.3 with A=Ba, and B=Co, comprising additionally 5-45 at %, preferably 15 to 30 at %, particularly preferably 25 at % Co.sub.3O.sub.4 (at % Co based on the total number of Co atoms in the perovskite ABO.sub.3 and 0.5 to 3 at %, preferably 1 to 2.5 at %, particularly preferably 2 at % (wherein the at % are referred to the total number of B cations in the perovskite ABO.sub.3) Ti as dopant. Preferably, the mixed oxide has the stoichiometric formula BaCo.sub.1xTi.sub.xO.sub.3:Co.sub.3O.sub.4 with x=0.005 to 0.03, preferably x=0.01 to 0.025, particularly preferably x=0.02, wherein defines the vacancies in the perovskite structure and is in the range of about 0.1 to 0.8, preferably 0.3 to 0.7, particularly preferably about 0.5 to 0.6. Further disclosed are a catalyst and an anode comprising the mixed oxide, the use of the catalyst in alkaline water electrolysis or in metal-air batteries, the use of the mixed oxide for the preparation of an anode for alkaline water electrolysis or metal-air batteries. Further, manufacturing processes for a precursor solution for the mixed oxide and for the inventive anode are disclosed, as well as an amorphous mixed oxide having a Co:Ba ratio of about 2:1 and a TTB (Tetragonal Tungsten-Bronze)-like near structure obtainable by using the mixed oxide according to the invention as catalyst in the oxygen evolution reaction of alkaline water electrolysis, whereby said amorphous product is formed by leaching out Ba.