A method of preparing an ionomer of an ion exchange membrane with a recombination catalyst to prevent gas crossover of species, such as hydrogen and/or oxygen, to anodic and cathodic cell compartments of an electrochemical cell. An ionomer of an ion exchange membrane is prepared with a recombination catalyst. The ionomer is a proton or anion exchange polymer and the recombination catalyst, selected from the precious metals group, is provided in ionic form in a liquid metal salt solution. The ion exchange membrane is immersed into the liquid metal salt solution to exchange ionic ionomer ports with the ionic form of the recombination catalyst. The membrane is then assembled in the electrochemical cell and the ionic form of the recombination catalyst is at least partly reduced to metallic form by forcing hydrogen to permeate through the ionomer of the ion exchange membrane.

A gas diffusion electrode for a fuel cell which comprises a gas-permeable substrate that has functional groups is provided, said groups being capable of complexing cations, and catalytically active noble metal particles and/or atoms, said particles and/or atoms being bonded by the functional groups to a surface of a first flat side of the substrate and/or in a surface-proximal region of a first flat side of the substrate. The gas diffusion electrode according to the invention combines the functions of a gas diffusion layer and a catalytic layer in an integral component and is distinguished by a high long-term stability with respect to degradation phenomena of the catalyst.

This disclosure provides systems, methods, and apparatus related to electrode structures. In one aspect, a method includes: providing an electrode layer comprising a ceramic, the ceramic being porous; providing a catalyst precursor, the catalyst precursor being a cathode catalyst precursor or an anode catalyst precursor; infiltrating the catalyst precursor in a first side of the electrode layer; after the infiltrating operation, heating the electrode layer to about 750° C. to 950° C., the catalyst precursor forming a catalyst, the catalyst being a cathode catalyst or an anode catalyst; infiltrating the catalyst precursor in the first side of the electrode layer; after the infiltrating operation, heating the electrode layer to about 300° C. to 700° C., the catalyst precursor forming the catalyst, the catalyst being the cathode catalyst or the anode catalyst.

A porous carbon-based metal catalyst, a preparation method and application thereof are provided. The preparation method includes: successively performing activation, surface corrosion, nitrogen-doping treatment and graphitization treatment on washed micro-grade porous carbon, then performing sensitization treatment, and subsequently carrying out loading, reduction and other treatments of catalytic metal, so as to finally obtain the porous carbon-based metal catalyst. The porous carbon-based metal catalyst provided by the present application has excellent catalytic performance, is especially suitable for producing hydrogen by efficiently catalytically decomposing ammonia borane, is not prone to inactivation, and is easy to regenerate after inactivation. Meanwhile, the preparation method is environmental-friendly, is suitable for large-scale production and has a wide application prospect in the fields such as hydrogen fuel batteries.

An anode catalyst layer for a fuel cell includes: electrode catalyst particles; a carbon carrier carrying the electrode catalyst particles; water electrolysis catalyst particles; a proton-conductive binder; and a graphitized carbon, wherein the content of graphitized carbon in the anode catalyst layer for a fuel cell is 15-70 volume % with respect to the total volume of the electrode catalyst particles, the carbon carrier, and the graphitized carbon.

This anode catalyst layer for a fuel cell contains electrode catalyst particles, a carbon carrier on which the electrode catalyst particles are loaded, water electrolysis catalyst particles, a proton-conducting binder, and graphitized carbon. At least part of the carbon carrier has a crystallite size La of 3.0 nm or more.

This anode catalyst layer for a fuel cell contains electrode catalyst particles, a carbon carrier on which the electrode catalyst particles are loaded, water electrolysis catalyst particles, a proton-conducting binder, and graphitized carbon. The graphitized carbon has a bulk density of 0.50/cm.sup.3 or less.

A gas diffusion electrode for a fuel cell which comprises a gas-permeable substrate that has functional groups is provided, said groups being capable of complexing cations, and catalytically active noble metal particles and/or atoms, said particles and/or atoms being bonded by the functional groups to a surface of a first flat side of the substrate and/or in a surface-proximal region of a first flat side of the substrate. The gas diffusion electrode according to the invention combines the functions of a gas diffusion layer and a catalytic layer in an integral component and is distinguished by a high long-term stability with respect to degradation phenomena of the catalyst.

The invention relates to aprocess for producing a catalyst comprising an intermetallic com-pound comprisingmixing of a salt comprising a metal selected from the group consisting of Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Auand Ru, a salt comprising a metal selected from the group consist-ing of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba,Sc, Y, La and the lanthanides, and a reducing agentcomprising a salt,wherein the mixing is carried out at a temperature where all compo-nents are solid; reacting the mixture obtained to form an intermetallic compound by heating said to a temperature in the range between the melting temperature of thereducing agent and the melting temperature of the intermetallic compound and holdingthe temperaturefor1 minute to 600 minutes; and washing the mixture to removeby-products andremainders of the salt of the cations of the reducing agent and at least one of the anions of the salts used in the first step. The invention further relates to a catalyst obtained by the process.

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 0.3 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.1−xTi.sub.xO.sub.3−δ: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 δ 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.