Abstract: A detecting electrode comprises a first cermet electrode layer formed directly on a solid electrolyte layer and a second cermet electrode layer formed on the first cermet electrode layer. A ratio between an alloy of Pt—Rh and ZrO2 in the first cermet electrode layer ranges from 20:80 to 50:50 by volume ratio. On the other hand, a ratio between an alloy of Pt—Rh and ZrO2 in the second cermet electrode layer ranges from 60:40 to 50:50 by volume ratio.

Abstract: A detecting electrode comprises a first cermet electrode layer formed directly on a solid electrolyte layer and a second cermet electrode layer formed on the first cermet electrode layer. The ratio between Pt and Rh in the first cermet electrode layer ranges from 100:0 to 25:75 by weight. The ratio between Pt and Rh in the second cermet electrode layer ranges from 25:75 to 0:100 by weight.

Abstract: A solution useful for forming a solid that supports mass transfer includes carbon nanotubes and a solvent. Solids formed using the solution thereby have carbon nanotubes dispersed therein that are useful for communicating gas and/or electric charges within the solid. Catalyst layers of the invention that include carbon nanotubes can provide high levels of efficiency while requiring low catalyst concentrations.

Abstract: A large surface area electrode well-suited to electrochemical applications is produced by winding many turns of a metallic fiber tow on to a sheet metal rectangle. In the preferred embodiment, an anode that can be used to purify water by electrochemical production of hydroxyl free radical is made by winding titanium fiber tow on to a rectangular substrate made of titanium sheet, and applying a suitable multilayered electrocatalytic coating. Made of other metals, an electrode of this description can also serve as the cathode of an electrochemical cell, or as a battery plaque.

Abstract: An oxygen-depolarized cathode for aqueous hydrochloric acid electrolysis membrane cells is described, the cathode being in contact with the membrane and capable of preventing the release of hydrogen into oxygen even at the highest current densities. Hydrochloric acid may also be of technical grade with a concentration limited to 15%, whereas the operating temperature must not exceed 60° C. The cathode contains a mixture of rhodium sulphide and a metal of the platinum group applied in a single layer or alternatively applied separately in two distinct layers.

Abstract: A locally distributed electrode is made by placing a conducting metallic oxide layer and a counter electrode in contact with a noble metal electroplating solution and applying a negative potential to the metallic oxide layer relative to the counter electrode, such that the noble metal is electrodeposited from the solution preferentially at defect sites on a surface of the metallic oxide layer. The noble metal nuclei are selectively electrodeposited at the defect sites to form a locally distributed electrode made up of a dot matrix of metallic islands. For reversible electrochemical mirror (REM) devices, the presence of the noble metal renders mirror metal electrodeposition at the defect sites reversible so that the defects become part of the dot matrix electrode and extraneous deposition of the mirror metal on the conducting metallic oxide is avoided.

Abstract: A catalytic powder comprising a plurality of support metal particles with a porous coating (12) surrounding the metal particles (11), the porous coating comprising either an electrocatalytic metal or an electrocatalytic metal continuous phase in admixture with a particulate material (14). An electrode made with the catalytic powder and a method to make the electrode is also disclosed. The present invention is advantageous because the porous coating mixture is first applied to a powder rather than being applied directly to a metal substrate, thereby creating a large internal surface area on the electrode and accordingly, lower overpotential requirements.

Abstract: An electrochemical device (18) for generating a desired gas of the type includes an ionically conductive electrolyte layer (20), a porous electrode layer (22), and a current collector layer (16) that has a high electrical conductivity and is porous to a desired gas (24) generated by the electrochemical device (18). The current collector layer (16) is substantially formed as a film comprised of a layer of spherical refractory material objects (26) having a conductive coating (12) of a precious metal. The coated spherical objects (26) have a desired diameter (28) making them suitable for forming into the film.

Abstract: A rhodium sulfide electrocatalyst formed by heating an aqueous solution of rhodium salt until a steady state distribution of isomers is obtained and then sparging hydrogen sulfide into the solution to form the rhodium sulfide and a membrane electrode assembly with the said electrode and a process for electrolyzing hydrochloric acid.

Abstract: There is disclosed a method for cooper electrowinning and a modified lead electrode for use in such method. The modified electrode is suitable for use as an oxygen anode in low current density, oxygen-evolving applications.

Abstract: The present invention relates to an electrocatalytic coating and an electrode having the coating thereon, wherein the coating is a mixed metal oxide coating, preferably platinum group metal oxides, with or without low levels of valve metal oxides. The electrocatalytic coating can be used especially as an anode component of an electrolysis cell and in particular a cell for the electrolysis of aqueous chlor-alkali solutions.

Abstract: The present invention discloses a process for the production of a gas diffusion electrode, in particular for the electrolysis of an aqueous solution of hydrogen chloride, in a first step a) a dispersion of a catalyst containing a noble metal and of a proton-conducting ionomer in an organic solvent being sprayed onto an electrically conductive support optionally provided with a coating material containing an acetylene black/polytetrafluoroethylene mixture and, in a second step b), the organic solvent being removed.

Abstract: Described are preferred electrode structures which desirably include multiple thin conductive layers stably bonded to an electrode substrate through a bonding layer. Also described are preferred electrode structures which include reinforcing carbon layers, which include an embrittlement-sensitive material and a protective oxygen-free copper layer, and which include at least one thin metal layer including a bamboo grain pattern. Additional embodiments of the invention include electric cells incorporating such electrode structures, and methods for their operation.

Abstract: The invention relates to a gas diffusion electrode (1) comprising a hydrophobic gas diffusion layer (3b), a reaction layer (3a), and a hydrophilic layer (5) arranged in the mentioned order wherein the reaction layer (3a) is arranged to a barrier layer (4), which barrier layer (4), on its opposite side, is arranged to the hydrophilic layer (5). The invention also relates to a method for manufacturing such a gas diffusion electrode (1), and to an electrolytic cell, and use thereof.

Abstract: An oxygen-depolarised cathode for aqueous hydrchloric acid electrolysis membrane cells is described, the cathode being in contact with the membrane and capable of preventing the release of hydrogen into oxygen even at the highest current densities. Hydrochloric acid may also be of technical grade with a concentration limited to 15%, whereas the operating temperature must not exceed 60° C. The cathode contains a mixture of rhodium sulphide and a metal of the platinum group applied in a single layer or alternatively applied separately in two distinct layers.

Abstract: A solution useful for forming a solid that supports mass transfer includes carbon nanotubes and a solvent. Solids formed using the solution thereby have carbon nanotubes dispersed therein that are useful for communicating gas and/or electric charges within the solid. Catalyst layers of the invention that include carbon nanotubes can provide high levels of efficiency while requiring low catalyst concentrations.

Abstract: There are provided an electrode for electrolysis which takes into consideration safety to human bodies and environmental pollution upon disposal of the electrode, produces ozone with high efficiency and has excellent durability, a production process of the electrode, and an active oxygen producing device using the electrode. In an electrode 5 for electrolysis which has an electrode catalyst at least on the surface and produces ozone or active oxygen in for-treatment water by electrolysis, the electrode catalyst contains a dielectric which constitutes more than 70% of the surface area of the electrode catalyst.

Abstract: The present invention discloses a gas sensing device, an oxygen pumping cell, and a gas detection apparatus using the same for detecting lower ranges of gas concentration with high accuracy and stability. An under layer made of oxygen-ion-conductive solid electrolyte was formed between an electrolyte substrate and a sensing electrode, a conversion electrode or a gas treatment electrode. This allows the physical and chemical adhesion between these electrodes and the electrolyte substrate, thereby improving the sensing properties and stability.

Abstract: Disclosed is a microchip-based differential-type potentiometric oxygen gas sensor, which comprises a working electrode and a reference electrode. The working electrode is composed of a cobalt-plated electrode, a buffered hydrogel, and an ion sensitive gas permeable membrane while the reference electrode is composed of an oxygen non-sensitive silver chloride electrode and the same ion-selective gas-permeable membrane of working electrode. By taking advantage of the corrosion potential, the microchip-based oxygen gas sensor can accurately and quickly detect the content of dissolved oxygen in a sample solution. With this structure, the oxygen gas sensor is applied to a microchip-based all potentiometric multi-sensor capable of detecting two or more ions and gas species on a single chip.

Abstract: Preferred electrode devices (10) including a substrate (11) and cathode (13) and anode material (12) coated thereon in discreet locations are described. The cathode materials desirably include multiple layers of thin metal films (14). Preferred cell devices including conductive elements and a solid state source of charged ions for migration into and through the conductive elements are also described.

Abstract: An electrolytic process of ozone generation using platinum-coated titanium grid as cathode, &bgr;-PbO2 deposited on the grid as anode, and batteries in conjunction with supercapacitors as a DC power source is described. No membrane is required to separate the electrodes, and a neutral salt such as NaCl is used to enhance the generation of ozone gas. The electrolytic apparatus comprising a cell, the electrodes, and a bubbler can also be inserted directly in water that needs ozone treatment. As batteries can power the ozone generation, the apparatus can be disposed at point-of-use and away from the city electricity. The electrolytic apparatus can be used for sterilization of water for pharmaceutical industry, household water supply, for surface cleaning of semiconductors, meats, fish, fruits, as well as for disinfection of SPA water and personal hygiene.

Abstract: Described are preferred multilayer, thin-film electrodes (11) that have improved resistance to flaking or cracking under conditions of operation. Also described are electrolytic cells (17) incorporating such electrodes (11), and methods for selecting electrode materials to facilitate reaction rates, energy production, and/or to shift the average mass number of transmuted products to lighter or heavier values. Preferred electrodes (11) have a plurality of thin-film conductive layers (14) supported on generally concave surfaces (13).

Abstract: The invention is relative to an electrode for gas evolution in electrolytic and electrometallurgical industrial applications, made of a metal substrate having a surface morphology characterized by a combination of micro-roughness and macro-roughness which favors high adherence of a superficial catalytic layer in order to prevent detachment of the same and passivation of the substrate even under critical operating conditions.

Abstract: An electrode with large active surface area is made by winding a Ti-fiber tow around a rectangular Ti-plate, and an electrocatalytic coating of three layers is applied. A precoat comprising a mixture of iridium dioxide and tantalum pentoxide is applied first, using a solution of the corresponding chloride salts in hydrochloric acid with some nitric acid added to inhibit corrosion of the metal. A sealing coat is then applied, comprising tin dioxide doped with antimony, in order to improve adhesion of the final oxide coat to the precoat. The third and final coat comprises particles of titanium dioxide doped with niobium in the +4 oxidation cemented with titanium dioxide that is doped with antimony. Anodes of this description are preferably assembled together with corrosion resistant cathodes in an alternating sequence, with a plastic coated fiber glass mesh placed between the anodes and cathodes to prevent short circuiting.

Abstract: A catalytically active layer that is used, for example, as an electrode for a solid electrolyte-based sensor element of a gas sensor for determining a gas component in a gas mixture. The catalytically active layer includes a metallic component, that includes a noble metal in the form of platinum, rhodium, and/or palladium, and additionally a base metal. At least a portion of the originally present base metal is replaced by cavities in the metallic component.

Abstract: An electrolytic cell producing sodium chlorate uses an electrode, specifically an anode, having a surface or coating or treatment of a mixed metal oxide having ruthenium oxide as an electrocatalyst, a precious metal of the platinum group or its oxide as a stability enhancer, antimony oxide as an oxygen suppressant and a titanium oxide binder. The electrocatalytic coating is about 21 mole percent ruthenium oxide, about 2 mole percent iridium oxide, about 4 mole percent antimony oxide and the balance is titanium oxide. The coating is characterized by high durability and low oxygen content in an off-gas.

Abstract: A metal anode useful in a galvanic or impressed current cathodic protection system for a steel reinforced concrete article is a unitary, multi-plane, porous, metal anode strip or ribbon having a plurality of louvers defining a plane or planes at the lateral extremities of said louvers. In one embodiment, louvers extending in their long dimension longitudinally on the anode strip are spaced apart from adjacent louver units by an intermediate plane. Louvered anode strips consisting of a valve metal or alloy or mixture thereof are useful at an anode current density of up to about 20 milliamps per square foot. Louvered metal anodes comprising an electrocatalytically active coating on a valve metal substrate are useful at higher anode current densities. Sacrificial metal anodes such as zinc anodes are useful in galvanic cathodic protection systems.

Abstract: An electrodeionization apparatus and method of use includes an expanded conductive mesh electrode. The expanded conductive mesh electrode may be formed from any conductive material that is dimensionally stable and may be coated with conductive coating suitable for use in anode or cathode service. The expanded conductive mesh electrodes are formed by slitting a sheet of metal and pulling its sides in a direction perpendicular to the slits. The fabricated mesh may be flattened after stretching. The expanded conductive mesh electrodes typically have a diamond-shaped pattern of any size that provides support for an adjacent ion-permeable membrane while allowing an electrode or fluid stream to flow through. The mesh size typically has a long-wise dimension and a short-wise dimension. The conductive mesh electrode may also be placed against an endblock having fluid channels. These channels may be serpentine or parallel channels, which allow fluid flow to wash away any accumulation.

Abstract: A deposition process for coating a substrate with a ruthenium-containing oxide material, or a precursor thereof, is described. Preferably, the reagent solution is substantially devoid of a halide, such as chlorine. The coated substrate is useful as an electrode in a capacitor.

Abstract: A cathode comprising an electrically conductive substrate made of titanium, nickel, tantalum, zirconium, niobium, iron or alloys thereof, coated with an intermediate layer of oxides of titanium and of a precious metal, and with an outer layer comprising metal oxides of titanium, zirconium and a precious metal, can be used for the electrolysis of solutions, in particular for the electrolysis of aqueous solutions of alkali metal chlorides.

Abstract: Disclosed is A flow-through electrochemical reactor comprising a body having an internal chamber, and an inlet port and an outlet port in communication with said internal chamber to permit flow of wastewater therethrough, at least one porous anode arranged in said internal chamber such that the wastewater flowing between said inlet port and said outlet port flows through the pores of said at least one porous anode, said at least one porous anode having activity for the destruction of a target substance, and at least one cathode disposed in the internal chamber to permit an electric current to be established between said at least one cathode and said at least one anode, said electric current reducing the concentration of said target substance in the wastewater flowing through the chamber.

Abstract: An electrode having an electrocatalytic surface or coating composed of a mixture with iridium oxide is used in a reversible polarity electrolytic cell to selectively produce an alkali metal hypohalite, preferably sodium hypochlorite, from brine made from hard water. The mixture also may have a platinum group metal oxide and a valve metal oxide, preferably, ruthenium oxide and titanium oxide respectively.

Abstract: Gas Diffusion Electrodes (GDEs) play a pivotal role in clean energy production as well as in electrochemical processes and sensors. These gas-consuming electrodes are typically designed for liquid electrolyte systems such as phosphoric acid and alkaline fuel cells, and are commercially manufactured by hand or in a batch process. However, GDEs using the new electrolytes such as conductive polymer membranes demand improved electrode structures. This invention pertains to GDEs and gas diffusion media with new structures for systems using membrane electrode assemblies (MEAs), and automated methods of manufacture that lend themselves to continuous mass production. Unexpected improvements in gas and vapor transport through the electrode are realized by incorporating a new dispersion process in the construction, reformulating the applied mix with solution additives, and creating a novel coating structure on a conductive web.

Abstract: A cermet anode of an electrolytic cell is protected from thermal shock during cell start-up by coating an outer surface portion of the anode with a coating composition comprising carbon or aluminum or a mixture thereof. A particularly preferred coating composition includes an aluminum underlayer adjacent the outer surface portion of the anode, and a carbon overlayer overlying the underlayer. A support structure assembly supporting the cermet anode includes a high alumina ceramic material. In a preferred embodiment, the high alumina ceramic material is protected from thermal shock and corrosion by the coating composition of the invention.

Abstract: The present invention pertains to electrolytic diaphragm cells, particularly for the electrolysis of brine to produce chlorine and caustic. The innovation resides generally in the discovery that electrolytic cell operation can be desirably enhanced by compressing the diaphragm between anode and cathode. This compression of the diaphragm reduces the diaphragm thickness from an original thickness, e.g., from an original thickness of a diaphragm freshly deposited on a cathode. The reduced thickness of the diaphragm provides for cell operation that is less than zero gap operation. By maintaining the diaphragm under compression and in a reduced thickness, the cell operates with a narrower interelectrode gap and consequently at a desirably reduced cell voltage.

Abstract: A non-carbon metal-based anode of a cell for the electrowinning of aluminium comprising an electrically conductive metal substrate resistant to high temperature, the surface of which becomes passive and substantially inert to the electrolyte, and a coating adherent to the metal substrate making the surface of the anode electrochemically active for the oxidation of oxygen ions present at the electrolyte interface. The substrate metal may be selected from nickel, cobalt, chromium, molybdenum, tantalum and the Lanthanide series. The active constituents of the coating are for example oxides such as spinels or perovskites, oxyfluorides, phosphides or carbides, in particular ferrites. The active constituents may be coated onto the substrate from a slurry or suspension containing colloidal material and the electrochemically active material.

Abstract: An electrode (10, 112) containing platinum has its surface modified with sulfur, tellurium, or selenium, or compounds thereof, which renders the surface highly selective for the conversion of oxygen to hydrogen peroxide. The high selectivity of the electrode, and its ability to function in acidic electrolytes make it suitable to a variety of electrochemical processes. In a preferred embodiment, an oxygen concentration device (A) incorporating the electrode as a cathode (10) also includes an anode (12) and a selective membrane (14), formed from a solid polymer electrolyte material, between the anode and the cathode. An oxygen-containing atmosphere is brought into contact with the cathode where it is converted to hydrogen peroxide. The hydrogen peroxide passes through the membrane to the anode where it is reconverted to purified oxygen.

Abstract: An anode is configured to be used within a metal film plating apparatus. The anode has a substantially planar electric field generating portion and an electrolyte solution chemical reaction portion. The planar electric field generating portion is coated with an inert material that is impervious to the electrolyte solution. In one embodiment, the anode is formed as a perforated anode. In one aspect, the electric field generating portion is formed contiguous with the electrolyte solution chemical reaction portion. In another aspects, the planar electric field generating portion is formed as a distinct member from the electrolyte solution chemical reaction portion.

Abstract: The invention relates to a specific cathode comprising a substrate made of an element chosen from the group formed by titanium, nickel, tantalum, zirconium, niobium and alloys thereof, the said substrate being coated with an interlayer of a mixed oxide based on titanium and on ruthenium and with an external layer of metal oxides comprising titanium, zirconium and ruthenium. The subject of the invention is also its manufacturing process and its applications in electrolysis.

Abstract: The invention concerns a bipolar electrode with a semiconductor coating and a cathode, as well as a procedure for the electrolytic dissociation of water, especially for the recovery of hydrogen. The body material of the cathode and/or the anode in this procedure is preferably comprised of titanium or platinum coated titanium, whereby, on the anode an additional semiconductor coating is applied, said coating being preferentially titanium dioxide (TiO2), which is dosed with iron (Fe). The advantage of the bipolar electrode is that an increased volume of hydrogen per time unit can be recovered and further, with these bipolar electrodes a simple procedure at ambient surroundings and conditions is achieved without expensive equipment for hydrogen production. In addition the anode of the invented bipolar electrodes can also be radiated with UV-radiation for the purpose of an increase in efficiency.

Abstract: The invention is relative to an electrode for gas evolution in electrolytic and electrometallurgical industrial applications, made of a metal substrate having a surface morphology characterized by a combination of micro-roughness and macro-roughness which favors high adherence of a superficial catalytic layer in order to prevent detachment of the same and passivation of the substrate even under critical operating conditions.

Abstract: An electrolytic apparatus which comprises effecting electrolysis of an electrolytic solution in an electrolytic chamber separated from a reaction chamber by a hydrogen-storing metal member with one surface of the hydrogen-storing metal member as a cathode opposing an anode so that hydrogen thus produced is adsorbed by the hydrogen-storing metal member while allowing hydrogen thus adsorbed and a material to be treated to undergo continuous catalytic reaction in the reaction chamber on the other surface of the hydrogen-storing metal member to cause hydrogenation or reduction reaction by hydrogen thus adsorbed, wherein an electrolytic apparatus having a porous catalyst layer provided on the catalytic reaction surface of the hydrogen-storing metal member is used.

Abstract: An electrolysis cell (1) includes an anodic plate (3), a cathodic plate (4) and a PEM (2) sandwiched between these plates (3, 4). The cell also includes a layer (5) containing a catalyst for generation of ozone. The layer (5) contains lead dioxide and PTFE and is interposed between the anodic plate (3) and the PEM (2). At least some portion of the anodic plate surface contacting the layer (5) is coated with platinum (6). The electrode plates (3,4) are not only electrically conductive but also in some portions are permeable to gas and liquid. A PTFE dispersion, lead dioxide powder and volatile dispersion medium are mixed are kneaded. The PTFE concentration relative to lead dioxide in the mixture is 5% by weight. The kneaded mixture (20) is spread to be a half-dried sheet (20) on paraffin paper plate (22). The half-dried sheet (20) is left standing or heated in an atmosphere at or below 100° C. to volatilize the dispersion medium and become dry.

Abstract: An activated cathode comprising an electrically conductive substrate, an interlayer comprising a nickel oxide formed on the surface of the electrically conductive substrate, and a catalyst layer containing at least one lanthanum component selected from oxides and hydroxides of lanthanum metals and at least one platinum component selected from platinum metals and silver and oxides and hydroxides thereof formed on the interlayer. A process for the preparation of an activated cathode is also disclosed which comprises forming an interlayer comprising a nickel oxide on the surface of an electrically conductive substrate, and then forming a catalyst layer containing at least one lanthanum component selected from oxides and hydroxides of lanthanum metals and at least one platinum. component selected from platinum metals and silver and oxides and hydroxides thereof on the surface of the interlayer.

Abstract: This invention relates generally to an electrically conductive valve metal mesh of extreme void fraction. More particularly the invention relates in a most important aspect to an application thereof for an electrode structure in such a way as to prevent the corrosion of steel, including reinforcing steel in concrete, by cathodic protection.

Abstract: An electrode adapted for chromium plating from trivalent chromium baths which comprises a conductive base, an electrode material layer comprising iridium oxide formed thereon, and a porous layer formed on the surface of the electrode material layer. The porous can comprise an oxide containing at least one element selected from the group consisting of silicon, molybdenum, titanium, tantalum, zirconium, and tungsten. Use of this electrode for chromium plating reduces the oxidation of trivalent chromium into hexavalent chromium.

Abstract: A cathode for electrolysis comprising a hydrogen-occluding material for use in an electrolytic cell partitioned by the cathode into two chambers including a reaction chamber and an electrolysis chamber. The cell is arranged so that a reactant is reduced or hydrogenated in the reaction chamber. The cathode comprises an ion exchange membrane or porous membrane. A first layer made of a hydrogen-occluding metallic palladium or a palladium alloy is formed on the reaction chamber side of the membrane. A second layer which is a porous catalyst layer made of a platinum metal black or gold is formed on the first layer. Also disclosed is an electrolytic cell using the cathode for electrolysis.

Abstract: An electrolyzing electrode which is for electrolyzing a metal electrolytic solution, shows a long lifetime in use as an ordinary anode and has sufficient durability even when in a poor potential region, and a process for the production thereof. The electrolyzing electrode of the present invention has an undercoating layer which is formed of platinum metal and tantalum oxide and contains, as metals, 1 to 20 at % of platinum and 80 to 99 at % of tantalum, on an electrically conductive electrode substrate, has an intermediate layer which is formed of iridium oxide and tantalum oxide and contains, as metals, 70 to 99.9 at % of iridium and 0.1 to 30 at % of tantalum, on the undercoating layer, and further has an overcoating layer which is formed of platinum metal and iridium oxide and contains, as metals, 60 to 99.9 at % of platinum and 0.1 to 40 at % of iridium, on the intermediate layer.

Abstract: The invention relates to a process for the electrolysis of sodium chloride-containing brine with parallel operation of amalgam electrolysis units (5) and membrane electrolysis units (4) with a common brine circuit using a mercury-resistant oxygen consumable cathode in the membrane electrolysis unit (4).

Abstract: The present invention provides an improved anode formulation and an improved method of manufacture. More specifically, the invention provides a tri-layer anode having an improved service life when used, for example, for steel strip electrogalvinizing. In one embodiment of the invention, the anode is comprised of a titanium substrate which is roughened and heat treated and subsequently coated with a first coating of iridium oxide/tantalum oxide. After the anode is heat treated, it is next coated, preferably by an electrodeposition process with a second coating of platinum. Finally, the anode is coated with a third coating of iridium oxide/tantalum oxide and subsequently heat treated.