Abstract: A membrane-electrode assembly in a polymer electrolyte/proton exchange membrane fuel cell includes the electrodes (anode and cathode), with a thin layer of catalyzed conductive support particles bonded to either side of the membrane. Where the polymer membrane comprises pendant chains of fluorinated carbon atoms with mobile proton containing terminal groups, proton conductivity with the catalyst particles is improved by chemically attaching like pendant chains to carbon atoms at surfaces of carbon particles. In certain implementations, an amino aryl perfluorinated sulfonic acid precursor is prepared. This precursor is converted to an aryl diazonium cation in the presence of carbon particles. The diazonium cation is reduced to the aryl radical which reacts with carbon atoms of the carbon substrate.

Abstract: The invention relates to membrane-electrode assemblies for the electrolysis of water (electrolysis MEAs), which contain an ion-conducting membrane having a front and rear side; a first catalyst layer on the front side; a first gas diffusion layer on the front side; a second catalyst layer on the rear side, and a second gas diffusion layer on the rear side. The first gas diffusion layer has smaller planar dimensions than the ion-conducting membrane, whereas the second gas diffusion layer has essentially the same planar dimensions as the ion-conducting membrane (“semi-coextensive design”). The MEAs also comprise an unsupported free membrane surface that yields improved adhesion properties of the sealing material. The invention also relates to a method for producing the MEA products. Pressure-resistant, gastight and cost-effective membrane-electrode assemblies are obtained, that are used in PEM water electrolyzers, regenerative fuel cells or in other electrochemical devices.

Abstract: A method of preparing a supported catalyst, a supported catalyst prepared by the method, and a fuel cell using the supported catalyst. In particular, a method of preparing a supported catalyst by preparing a primary supported catalyst containing catalytic metal particles that are obtained by a primary gas phase reduction reaction of a portion of the final loading amount of a catalytic metal, and reducing the remaining portion of the catalytic metal by a secondary liquid phase reduction reaction using the primary supported catalyst. The supported catalyst contains catalytic metal particles having a very small average particle size, which are uniformly distributed on a carbon support at a high concentration, and thus exhibits maximal catalyst activity. A fuel cell produced using the supported catalyst has improved efficiency.

Abstract: A composite catalyst for a chemical reaction includes a porous metal catalyst that catalyzes a plurality of reactants to provide a reaction product, and a reaction-enhancing material disposed within pores defined by the porous metal catalyst. The reaction-enhancing material enhances attraction of at least one reactant of the plurality of reactants into the pores defined by the porous metal catalyst and enhances expulsion of the reaction product from the pores defined by the porous metal catalyst. A fuel cell according to an embodiment of the current invention has a first electrode, a second electrode spaced apart from the first electrode, and an electrolyte arranged between the first and the second electrodes. The at least one of the first and second electrodes is at least one of coated with or comprises a composite catalyst.

Abstract: A gas diffusion electrode comprises at least one gas diffusion media, at least one supported catalyst layer disposed on top of the gas diffusion media, the supported catalyst layer comprising at least one supported catalyst, and an unsupported catalyst layer disposed on top of the supported catalyst layer, the unsupported catalyst layer having a higher total catalyst loading than the supported catalyst layer.

Abstract: The present invention relates to a direct oxidation fuel cell system including at least one electricity generating element including at least one membrane-electrode assembly which includes an anode and a cathode on opposite sides of a polymer electrolyte membrane, and a separator. The direct oxidation fuel cell generates electricity through an electrochemical reaction of a fuel and an oxidant. An oxidant supplier supplies the electricity generating element with the oxidant. A fuel supplier supplies the anode with a combination of fuel and hydrogen to provide improved power output.

Abstract: A tubular fuel cell module having improved current collecting efficiency. In one embodiment, the fuel cell module includes: a fuel cell unit; a first current collector extending along an outer side of the fuel cell unit; and a second current collector wound around the first current collector and around the outer side of the fuel cell unit. Here, the outer side of the fuel cell unit is a curved outer side, the first current collector has a curved inner side facing the curved outer side of the fuel cell unit, and the curved inner side of first current collector is shaped to match the curved outer side of the fuel cell unit.

Abstract: A method of preparing a supported catalyst includes dissolving a cation exchange polymer in alcohol to prepare a solution containing cation exchange polymer; mixing the cation exchange polymer containing solution with a catalytic metal precursor or a solution containing catalytic metal precursor; heating the mixture after adjusting its pH to a predetermined range; adding a reducing agent to the resultant and stirring the solution to reduce the catalytic metal precursor; mixing the resultant with a catalyst support; adding a precipitating agent to the resultant to form precipitates; and filtering and drying the precipitates. The method of preparing a supported catalyst can provide a highly dispersed supported catalyst containing catalytic metal particles with a reduced average size regardless of the type of catalyst support, which provides better catalytic activity than conventional catalysts at the same loading amount of catalytic metal.

Abstract: A solid polymer electrolyte fuel cell includes a membrane electrode assembly having an anode, a cathode arranged facing the anode, and a polyelectrolyte membrane arranged between the anode and the cathode, and a pair of separator plates that are arranged facing each other so as to sandwich the membrane electrode assembly, and have an anode side gas channel for supplying a fuel gas to the anode, and a cathode side gas channel for supplying an oxidant gas to the cathode, formed thereon, wherein the catalyst layer of the anode contains at least one electrode catalyst selected from the group consisting of Pt particles and Pt alloy particles, having a particle diameter of from 6 to 10 nm, the catalyst layer of the anode has a thickness of from 1 to 5 ?m, Pt volume density in the catalyst layer of the anode is from 1 to 5 g/cm3, the catalyst layer of the cathode has a thickness of 10 ?m or more, and Pt volume density in the catalyst layer of the cathode is from 0.1 to 0.5 g/cm3.

Abstract: The invention is directed to iridium oxide based catalysts for use as anode catalysts in PEM water electrolysis. The claimed composite catalyst materials comprise iridium oxide (IrO2) and optionally ruthenium oxide (RuO2) in combination with a high surface area inorganic oxide (for example TiO2, Al2O3, ZrO2 and mixtures thereof). The inorganic oxide has a BET surface area in the range of 50 to 400 m2/g, a water solubility of lower than 0.15 g/l and is present in a quantity of less than 20 wt. % based on the total weight of the catalyst. The claimed catalyst materials are characterised by a low oxygen overvoltage and long lifetime in water electrolysis. The catalysts are used in electrodes, catalyst-coated membranes and membrane-electrode-assemblies for PEM electrolyzers as well as in regenerative fuel cells (RFC), sensors, and other electrochemical devices.

Abstract: According to at least one aspect of the present invention, a fuel cell electrode assembly is provided. In one embodiment, the fuel cell electrode assembly includes a substrate and a plurality of catalyst regions supported on the substrate to provide a passage way formed between the catalyst regions for passing fuel cell reactants, at least a portion of the plurality of catalyst regions including a number of atomic layers of catalyst metals. In certain instances, the number of atomic layers of catalyst metals is greater than zero and less than 300. In certain other instances, the number of atomic layers of catalyst metals is between 1 and 100. In yet certain other instances, the number of atomic layers of catalyst metals is between 1 and 20.

Abstract: Noble metal catalysts and methods for producing the catalysts are provided. The catalysts are useful in applications such as fuel cells. The catalysts exhibit reduced agglomeration of catalyst particles as compared to conventional noble metal catalysts.

Abstract: According to one aspect of the present invention, a catalyst assembly is provided for use in a fuel cell. In one embodiment, the catalyst assembly includes a first layer containing a first noble metal catalyst supported on a first support material having a first average surface area, and a second layer containing a second noble metal catalyst supported on a second support material having a second average surface area less than the first average surface area. In another embodiment, the catalyst assembly is disposed next to an ionic exchange membrane, wherein the first layer is positioned between the first layer and the ionic exchange membrane. In yet another embodiment, the first and second support materials collectively define channels of differential hydrophobicity.

Abstract: According to one aspect of the present invention, a hybrid catalyst system is provided. In one embodiment, the hybrid catalyst system includes a support mixture and a catalyst material supported on the support mixture, wherein the support mixture includes a first support material having a first average surface area and a second support material having a second average surface area different from the first average surface area, the first and second support materials collectively defining regions of differential hydrophobicity. In certain instances, the hybrid catalyst system can be configured as a catalyst layer to be disposed next to a proton exchange membrane of a fuel cell.

Abstract: In one aspect a substrate such as a sheet metal product, in particular for use as a bipolar plate in a fuel cell or in an electrolyzer, is characterized in that it has, on at least one side, a conductive and corrosion-resistant protective coating of a metal oxide having a treatment which ensures the conductivity. The coating can be produced by introducing a piece of sheet metal into a coating plant and providing it with the conductive and corrosion-resistant protective coating of the metal oxide. In another aspect, an electrochemical cell such as a fuel cell comprises an electrically conductive contact element having a first surface facing an electrode for conducting electrical current, and the contact element comprises an electrically conductive substrate and an electrically conductive coating comprising a doped metal oxide, desirably a doped tin oxide, and preferably a fluorine doped tin oxide.

Abstract: A solid oxide fuel cell (SOFC) includes a cathode electrode, a solid oxide electrolyte, and an anode electrode. The anode electrode includes a first portion made of a first anode material and a second portion made of a second anode material. The first anode material is a higher performance, lower oxidation resistant material than the second anode material.

Abstract: A direct oxidation fuel cell of this invention has at least one unit cell including: a membrane-electrode assembly including an electrolyte membrane sandwiched between an anode and a cathode, each of the anode and the cathode including a catalyst layer and a diffusion layer; an anode-side separator with a fuel flow channel for supplying a fuel to the anode; and a cathode-side separator with an oxidant flow channel for supplying an oxidant to the cathode. The catalyst layer of at least one of the anode and the cathode includes high-porosity regions and low-porosity regions, and the high-porosity regions and the low-porosity regions are arranged in a mixed configuration.

Abstract: A method for improving performance of an SOFC by impregnation of the cathode with metallic silver. A solution of AgNO3 in acetonitrile is imbibed into a perovskite cathode fabricated on a electrolyte layer supported by an anode, defining an SOFC cell. The cathode imbibition may be repeated a plurality of times as may be needed depending upon the thickness of the cathode. The amount of solution soaked into the cathode results a total final weight percent of Ag in the cathode between about 0.5% and about 10%. The cathode is then fired in air at high temperature to drive off the acetonitrile and to reduce the silver ions to metallic silver. In this way, cathode electrical resistance may be reduced by as much as 52%.

Abstract: The present teachings relate to an electrochemical system including an electrochemical device and multiple independent circuits which permit independent control of the reaction rates at different sections of the electrochemical device. The electrochemical device can be a fuel cell or an electrolyzer, and can include a common electrode in electrical communication with two or more independent circuits. The present teachings also relate to operating methods of the electrochemical system described.

Abstract: One embodiment includes a method of forming a hydrophilic particle containing electrode including providing a catalyst; providing hydrophilic particles suspended in a liquid to form a liquid suspension; contacting said catalyst with said liquid suspension; and, drying said liquid suspension contacting said catalyst to leave said hydrophilic particles attached to said catalyst.

Abstract: A fuel cell includes a first electrically conductive plate and a first gas diffusion layer. The first gas diffusion layer is disposed over the first electrically conductive plate. Characteristically, the first gas diffusion layer comprises a first fibrous sheet having fibers coated with an electrically conductive layer. A first catalyst layer is disposed over the first gas diffusion layer and an ion conducting membrane is disposed over the first catalyst layer. The fuel cell also includes a second catalyst layer disposed over the ion conducting membrane with a second gas diffusion layer disposed over the second catalyst layer. A second electrically conductive plate is disposed over the second gas diffusion layer. Methods for forming the gas diffusion layers and the fuel cell are also provided.

Abstract: According to at least one aspect of the present invention, a fuel cell catalyst layer is provided. In one embodiment, the fuel cell catalyst layer includes first spaced apart strands extending longitudinally in a first direction, second spaced apart strands extending longitudinally in a second direction, the first and second spaced apart strands collectively defining openings bounded by an adjacent pair of the first spaced apart strands and an adjacent pair of the second spaced apart strands, a number of wires extending longitudinally in a third direction from one of the first and second spaced apart strands, and a catalyst contacting at least a portion of the plurality of wires.

Abstract: A structure of fuel cell electrode comprises a diffusion layer having a surface, a conductive particle layer formed on the surface of the diffusion layer and a catalyst layer. The conductive particle layer has a plurality of conductive particles and a concavo-convex surface being composed of the conductive particles. The catalyst layer is formed on the concavo-convex surface of the conductive particle layer.

Abstract: One embodiment includes at least one of the anode and cathode of a fuel cell comprises a first layer and a second layer in intimate contact with each other. Both the first layer and the second layer comprise a catalyst capable of catalyzing an electrochemical reaction of a reactant gas. The second layer has a higher porosity than the first layer. A membrane electrode assembly (MEA) based on the layered electrode configuration and a process of making a fuel cell are also described.

Abstract: The membrane-electrode assembly of the present invention includes an anode and a cathode facing each other, and a polymer electrolyte membrane interposed therebetween. At least one of the anode and the cathode includes an electrode substrate and a metal catalyst layer disposed thereon. The metal catalyst layer includes a metal catalyst and a liquid crystal material.

Abstract: A membrane-electrode assembly comprising a cathode catalyst layer for reducing an oxidant gas, a polymer electrolyte membrane and an anode catalyst layer, the polymer electrolyte membrane being sandwiched between the catalyst layers, wherein the cathode catalyst layer exhibits super-water-repellency. The disclosure is also concerned with a method of manufacturing the membrane-electrode assembly and a fuel cell using the membrane-electrode assembly.

Abstract: A method for the deposition of metals in bacterial cellulose and for the employment of the metallized bacterial cellulose in the construction of fuel cells and other electronic devices is disclosed. The method for impregnating bacterial cellulose with a metal comprises placing a bacterial cellulose matrix in a solution of a metal salt such that the metal salt is reduced to metallic form and the metal precipitates in or on the matrix. The method for the construction of a fuel cell comprises placing a hydrated bacterial cellulose support structure in a solution of a metal salt such that the metal precipitates in or on the support structure, inserting contact wires into two pieces of the metal impregnated support structure, placing the two pieces of metal impregnated support structure on opposite sides of a layer of hydrated bacterial cellulose, and dehydrating the three layer structure to create a fuel cell.

Abstract: The invention relates to a sulphide catalyst for electrochemical reduction of oxygen particularly stable in chemically aggressive environments such as chlorinated hydrochloric acid. The catalyst of the invention comprises a noble metal sulphide single crystalline phase supported on a conductive carbon essentially free of zerovalent metal and of metal oxide phases, obtainable by reduction of metal precursor salts and thio-precursors with a borohydride or other strong reducing agent.

Abstract: The invention provides an electrode and an electrochemical device including the electrode. The electrode comprises a spatial confining structure such as grooves and an active compound such as glucose oxidase (GOx). The grooves spatially confines GOx, and stabilizes its enzymatic activity. Also provided is a method of stabilizing the activity of an active compound such as GOx. The invention can be widely used in development of an energy-generation device such as a fuel cell, a memory, an electrochemical reactor, a supercapacitor, a biosensor and a medical device thereof such as artificial pancreas, and a sensor such as detector of redox reactant.

Abstract: A polymer electrolyte having a repetitive structure represented by the following formula (1): wherein B represents a single bond or a bivalent group, A represents a bivalent aromatic group, Y represents —SO2—, —SO— or —CO—, R1 represents a substituent, n1 represents an integer of from 0 to 3, L represents a perfluoroalkylene group, and M represents an ionic group.

Abstract: A fuel reformer which can easily achieve high weight energy density and high volume energy density, and a method for producing the fuel reformer with ease and high efficiency as well as an electrode for electrochemical device, such as a fuel cell, and an electrochemical device are provided. The present invention is to feed hydrogen obtained from a fuel reformer having a catalyst layer containing Pt for taking out hydrogen from a liquid fuel, such as methanol, and a hydrogen permeable layer, such as a Pd thin film, which is impermeable to liquid and permeable to hydrogen to an electrochemical device such as a fuel cell, which comprises a negative electrode, a positive electrode and a proton conductive film sandwiched therebetween. The present invention provides a method of producing the hydrogen permeable layer in the reformer by forming the hydrogen permeable layer and the catalyst layer on a base layer comprising Al or the like, and removing the base layer by dissolution.

Abstract: A system and method for improving electrochemical power sources through the dispensing encapsulation and dispersion into galvanic chambers of an electrochemical cell. Features of the method include the optimization of the concentration levels of chemicals involved in desired energy producing reactions.

Abstract: Improved polymer-based materials are described, for example for use as an electrode binder in a fuel cell. A fuel cell according to an example of the present invention comprises a first electrode including a catalyst and an electrode binder, a second electrode, and an electrolyte located between the first electrode and the second electrode. The electrolyte may be a proton-exchange membrane (PEM). The electrode binder includes one or more polymers, such as a polyphosphazene.

Abstract: The present invention generally relates to electrochemical devices such as fuel cells and, in particular, to various component configurations including configurations for converting common fuels directly into electricity without additional fuel reforming or processing. Certain aspects of the invention are generally directed to configurations in which an anode of the device surrounds the electrolyte and/or the cathode of the device. In some embodiments, all single cells in a fuel cell stack share a common anode fuel chamber. The anode, in some cases, may be exposed to a fuel. In one set of embodiments, the anode of the device may be fluid during operation of the fuel cell, and in some cases, a porous container may be used to contain the anode during operation of the fuel cell. Other aspects of the invention relate to methods of making such devices, methods of promoting the making or use of such devices, and the like.

Abstract: The present invention relates to an electrochemical device. The device features an anode constructed of materials such that the device can be chemically recharged. In addition, the device is capable of switching between operating as a fuel cell or as a battery. The switch can occur without cessation of electrical output. In certain aspects of the invention, the device is capable of operating at a temperature of less than 1000° C. Other aspects feature a liquid anode which allows higher output, dispersion of fuel and minimal stresses in an interface comprising the anode. Preferably the anode is a liquid at a temperature of less than 1000° C. The invention also relates to methods for energy conversion in which a continual electrical output can be produced in both the presence of fuel without anode consumption or the absence of fuel.

Abstract: The present invention measures a quantity of attachment (such as density) of a material (such as catalyst and promoter) attached to a carrier. A carrier 1 includes attachment holes 12 to which a catalyst 24 attaches, and non-attachment holes 14 to which the catalyst 24 does not attach, where extension directions of the attachment holes 12 and the non-attachment holes 14 are parallel with each other (perpendicular to a first end surface 1a), and are opened on the first end surface 1a and a second end surface 1b. An attachment quantity measurement device includes an electromagnetic wave output device 2 that outputs a terahertz wave at a frequency equal to or more than 0.

Abstract: A composition useful in electrodes provides higher power capability through the use of nanoparticle catalysts present in the composition. Nanoparticles of transition metals are preferred such as manganese, nickel, cobalt, iron, palladium, ruthenium, gold, silver, and lead, as well as alloys thereof, and respective oxides. These nanoparticle catalysts can substantially replace or eliminate platinum as a catalyst for certain electrochemical reactions. Electrodes, used as anodes, cathodes, or both, using such catalysts have applications relating to metal-air batteries, hydrogen fuel cells (PEMFCs), direct methanol fuel cells (DMFCs), direct oxidation fuel cells (DOFCs), and other air or oxygen breathing electrochemical systems as well as some liquid diffusion electrodes.

Abstract: A fuel cell of the present invention comprises a cathode and an anode, one or both of the anode and the cathode including a catalyst comprising a bundle of longitudinally aligned graphitic carbon nanotubes including a catalytically active transition metal incorporated longitudinally and atomically distributed throughout the graphitic carbon walls of said nanotubes. The nanotubes also include nitrogen atoms and/or ions chemically bonded to the graphitic carbon and to the transition metal. Preferably, the transition metal comprises at least one metal selected from the group consisting of Fe, Co, Ni, Mn, and Cr.

Abstract: A fuel cell including a membrane electrode assembly composed of a ionically conductive member sandwiched between a pair of electrodes. At least one of the electrodes including a catalyst loading characterized by catalytic activity that varies in proportion to the catalyst loading. Moreover, the fuel cell includes a flow path for supplying gaseous reactants to the electrodes and the catalyst loading is varied according to the flow path geometry.

Abstract: A method for preparing an electrode in which droplets of a first electrode ink composition and droplets of a second electrode ink composition are ejected from an ink jet device onto a base material. The first electrode ink composition contains at least one electrode active material and the second electrode ink composition contains at least one binder material. The two ink compositions are deposited in combination to form one of a positive electrode and a negative electrode layer. The resulting electrode is suitable for use in a battery.

Abstract: A polymer electrolyte membrane including an ionic conducting polymer and a light-irradiated product of a photoacid generator (PAG), a method of manufacturing the same, and a fuel cell using the same. The polymer electrolyte membrane has excellent proton conductivity and homogeneity by radiating light such as UV light onto the PAG, thereby producing an acid radical which generates an acid. The polymer electrolyte membrane also suppresses methanol crossover well. The polymer electrolyte membrane can be used as an electrolyte membrane of a fuel cell, for example, a direct methanol fuel cell.

Abstract: An electrode catalyst for a fuel cell, which has improved performance compared with conventional platinum alloy catalysts, a method for producing the electrode catalyst, and a polymer electrolyte fuel cell using the electrode catalyst are provided. The electrode catalyst for a fuel cell comprises a noble-metal-non-precious metal alloy that has a core-shell structure supported on a conductive carrier. The composition of the catalyst components of the shell is such that the amount of the noble metal is greater than or equal to the amount of the non-precious metal.

Abstract: A corrosion-resistant electrode catalyst for oxygen reduction includes a main catalyst composed of at least one transition metal oxide selected from oxygen-deficient ZrO2, Ta2O5, Nb2O5, TiO2, V2O5, MoO3, and WO3 and a co-catalyst composed of gold. The electrode catalyst is used in contact with an acidic electrolyte at a potential at least 0.4 V higher than the reversible hydrogen electrode potential. The catalyst may be used, for example, in such a form that the transition metal oxide in the form of fine particles and gold in the form of fine particles, or fine particles including fine gold particles coated with the transition metal oxide are dispersed on a catalyst carrier which is an electron conductive powder. This electrode catalyst is suitable as an electrode catalyst for an electrochemical system using an acidic electrolyte in the fields of water electrolysis, inorganic/organic electrolysis, fuel cells, etc.

Abstract: The present invention provides an oxygen gas diffusion cathode for sodium chloride electrolysis comprising: a porous conductive substrate comprising silver, a hydrophobic material and a carbon material; a catalyst comprising silver and palladium, coated on the porous conductive substrate.

Abstract: A flow field plate for fuel cell applications includes a metal with a carbon layer disposed over at least a portion of the metal plate. The carbon layer is overcoated with a silicon oxide layer to form a silicon oxide/carbon bilayer. The silicon oxide/carbon bilayer may be activated to increase hydrophilicity. The flow field plate is included in a fuel cell with a minimal increase in contact resistance. Methods for forming the flow field plates are also provided.

Abstract: An electrode for a fuel cell includes an electrode substrate and a catalyst layer on the electrode substrate. The catalyst layer includes an active catalyst and a heteropoly acid additive including a heteropoly acid supported by an inorganic carrier.

Abstract: A method of manufacturing an anode for a fuel cell including: performing an acid treatment for a carbon-based compound; washing the resultant obtained from the acid treatment with water and then performing a freeze-drying (lyophilization) process; forming a microporous diffusion layer by dispersing the lyophilized resultant in a solvent, coating the dispersed resultant on a porous carbon support, and drying; and forming a catalyst layer on top of the microporous diffusion layer, an anode for a fuel cell obtained according to the method herein, and a fuel cell using the same. An anode having improved efficiency on liquid fuel diffusion can be obtained when using the fuel diffusion layer including the microporous diffusion layer formed of the carbon-based compounds obtained after an acid treatment and a freeze-drying process according to the present invention. A fuel cell having improved performance can be manufactured by using such an anode.

Abstract: The invention provides an electrode comprising an electrically conductive material having a surface capable of producing surface enhanced Raman scattering of incident light from a complex adsorbed at the surface of the electrode, the complex including the electrically conductive material combined with a second material that is substantially reducible and not substantially oxidizable. The surface of the electrode can be microroughened. The invention also includes a method for making various embodiments of the electrode, and a method of generating electricity using the electrode. In accordance with a further aspect of the invention, a fuel cell is provided including the electrode of the invention.

Abstract: An oxygen-reducing catalyst layer, and a method of making the oxygen-reducing catalyst layer, where the oxygen-reducing catalyst layer includes a catalytic material film disposed on a substrate with the use of physical vapor deposition and thermal treatment. The catalytic material film includes a transition metal that is substantially free of platinum. At least one of the physical vapor deposition and the thermal treatment is performed in a processing environment comprising a nitrogen-containing gas.

Abstract: The invention relates to an ink for producing catalyst layers for electrochemical devices. The ink comprises catalyst material, ionomer material, water and at least one organic solvent. The organic solvent belongs to the class of tertiary alcohol's and/or the class of aliphatic diketones and bears functional groups which are stable to oxidative degradation in the ink. This prevents formation of decomposition products in the ink. The ink of the invention displays a high storage stability and is used for producing catalyst-coated substrates for electrochemical devices, in particular fuel cells (PEMFCs, DMFCs).