Abstract: A method for surface treatment of a metal substrate, suitable for use as electrode support in electrochemical processes by: (a) immersion of the metal substrate and of at least one counter electrode in an electrolyte selected from hydrochloric acid, nitric acid, boric acid or sulfuric acid at a weight concentration of between 10-40%; (b) application of an anodic current density to the metal substrate of between 0.1 and 30 A/dm2 for a time of between 0.5 and 120 minutes. An electrode for gas evolution in electrochemical processes obtained from a correspondingly treated substrate.

Abstract: The invention relates to an electrode suitable for use as a cathode for hydrogen evolution in industrial electrolytic processes. The electrode comprises a metallic substrate, an internal catalytic layer containing rhodium and an external catalytic layer containing ruthenium.

Abstract: The invention relates to an electrode for electrolytic processes, particularly to a cathode suitable for hydrogen evolution in an industrial electrolysis process comprising a metal substrate coated with an external catalytic layer containing crystalline ruthenium oxide having a highly ordered rutile-type structure with Ru Ru and Ru O bond length characterized by a Debye-Waller factor lower than a critical value. The catalytic outer layer may contain rare earth oxides, such as praseodymium. The electrode may also comprise an internal catalytic thin layer platinum-based, which gives an enhanced protection against accidental current reversal events.

Abstract: An electrode suitable for use as hydrogen-evolving cathode in electrolytic processes is obtained by thermal decomposition of a precursor consisting of an acetic solution of nitrates of ruthenium, and optionally of rare earths. The electrode displays a low cathodic hydrogen evolution overpotential, an improved tolerance to current reversal phenomena and a high duration in industrial operating conditions.

Abstract: The invention relates to an electrode for electrolytic processes, particularly to a cathode suitable for hydrogen evolution in an industrial electrolysis process comprising a metal substrate coated with an external catalytic layer containing crystalline ruthenium oxide having a highly ordered rutile-type structure with Ru Ru and Ru O bond length characterised by a Debye-Waller factor lower than a critical value. The catalytic outer layer may contain rare earth oxides, such as praseodymium. The electrode may also comprise an internal catalytic thin layer platinum-based, which gives an enhanced protection against accidental current reversal events.

Abstract: An electrode suitable for use as hydrogen-evolving cathode in electrolytic processes is obtained by thermal decomposition of a precursor consisting of an acetic solution of nitrates of ruthenium, and optionally of rare earths. The electrode displays a low cathodic hydrogen evolution overpotential, an improved tolerance to current reversal phenomena and a high duration in industrial operating conditions.

Abstract: A cathode for electrolytic processes, particularly suitable for hydrogen evolution in chlor-alkali electrolysis comprises a metal substrate provided with a catalytic coating made of two layers containing palladium, rare earths (such as praseodymium) and a noble component selected between platinum and ruthenium. The rare earth percent amount by weight is lower in the outer layer than in the inner layer.

Abstract: A cathode for electrolytic processes, particularly suitable for hydrogen evolution in chlor-alkali electrolysis comprises a metal substrate provided with a catalytic coating made of two layers containing palladium, rare earths (such as praseodymium) and a noble component selected between platinum and ruthenium. The rare earth percent amount by weight is lower in the outer layer than in the inner layer.

Abstract: The invention relates to a cathode for electrolytic processes with evolution of hydrogen comprising a metal substrate with a noble metal-based activation layer and two protective layers, one interposed between the activation layer and the substrate and one external, containing an electroless-depositable alloy of a metal comprising one of nickel, cobalt and iron with a non-metal selected from phosphorus and boron, with the optional addition of a transition element selected between tungsten and rhenium.