Electrode with electrocatalytic surface

In a method of forming an electrode for use in electrolytic processes comprising a base of film-forming metal with an operative electrocatalytic outer surface formed as an integral surface film of the film-forming metal base incorporating therein a platinum-group metal or compound thereof as electrocatalyst, the improvement comprising forming said electrocatalytic outer surface by a surface treatment by applying to the surface of the film-forming metal base at least one layer of a solution of at least one thermodecomposable compound which consists essentially of a platinum-group metal compound, drying and heating each applied layer to decompose said compound in a manner similar to methods known per se for the formation of platinum-group metal and platinum-metal oxide coatings, wherein said solution contains a halide agent which attacks the film-forming metal base and converts metal from the base into ions which are converted into a compound of the film-forming metal during the heating step, and wherein the concentration of said halide agent in the solution, the concentration of the platinum-group metal compound(s) in the solution, the drying, the heating and the number of applied layers are such that during the heating of each layer including the last layer, the electrocatalyst formed from the decomposed platinum-group metal compound is incorporated fully in a simultaneously-formed surface film of film-forming metal compound grown up from the base as a result of said halide agent attacking the film-forming metal base thereby forming an electrocatalytic outer surface, said outer surface being the surface film of film-forming metal compound integral with and wholly containing the electrocatalyst formed from the decomposed platinum-group metal compound.

In the production of an electrode for use in electrolytic processes, a method of activating the surface of a film-forming metal comprising applying to the surface of the film-forming metal at least one layer of a solution of at least one thermodecomposable compound which consists essentially of a platinum group metal compound, drying and heating each applied layer to decompose said compound, the improvement comprising said method is a surface treatment wherein a surface film of a compound of the film-forming metal which is electrocatalytic and electroconductive is formed by application of a solution containing a halide agent which attacks the film-forming metal surface and converts metal from the surface into ions which are converted into the compound of the film-forming metal during the heating step, wherein the concentration of said halide agent in the solution, the concentration of the platinum-group metal compound in the solution, the drying, the heating and the number of applied layers are such that during the heating of each layer including the last layer, the electrocatalyst formed from the decomposed platinum-group metal compound is incorporated fully in a simultaneously formed surface film of film-forming metal compound grown up from the film-forming metal as a result of said halide agent attacking the film-forming metal thereby forming an electrocatalytic outer surface, said outer surface being the surface film of film-forming metal compound integral with and wholly containing the electrocatalyst formed from the decomposed platinum-group metal compound.

In an electrode for use in electrolytic processes comprising particles of film-forming metal having an electrocatalytic surface formed by applying to the film-forming metal particles at least one layer of a solution of at least one thermodecomposable compound which consists essentially of a platinum-group metal compound, drying and heating each applied layer to decompose said compound, the improvement comprising a surface film of a compound of the film-forming metal which is electrocatalytic and electroconductive is formed on the particles by a surface treatment by applying a solution containing a halide agent which attacks the film-forming metal surface of the particles and converts metal from the surface into ions which are converted into the compound of the film-forming metal during the heating step, and wherein the concentration of said agent in the solution, the concentration of the platinum-group metal compound(s) in the solution, the drying, the heating and the number of applied layers are such that during the heating of each layer including the last one, the electrocatalyst formed from the decomposed platinum group metal compound is incorporated fully in a simultaneously-formed surface film of film-forming metal compound grown up on the surface of the particles as a result of said halide agent attacking the film-forming metal particles thereby forming an electrocatalytic outer surface, said outer surface being the surface film of film-forming metal compound integral with and wholly containing the electrocatalyst formed from the decomposed platinum-group metal compound.

In an electrode for use in electrolytic processes comprising a base of film-forming metal with an operative electrocatalytic outer surface formed as an integral surface film of the film-forming metal base incorporating therein a platinum group metal or compound thereof as electrocatalyst, the improvement comprising said electrocatalytic outer surface is formed by a surface treatment by applying to the surface of the film-forming metal base at least one layer of a solution of at least one thermodecomposable compound which consists essentially of a platinum-group metal compound, drying and heating each applied layer to decompose said compound, wherein said solution contains a halide agent which attacks the film-forming metal base and converts metal from the base into ions which are converted into a film-forming metal compound during the heating step, and wherein the concentration of said halide agent in the solution and the concentration of said platinum-group metal compound in the solution and the drying and the heat procedure and the number of applied layers of the solution are such that during the heating of each layer, including the last layer, the electrocatalytic surface thus formed is an integral film of decomposed platinum-group metal compound and film-forming metal compound wherein the film-forming metal compound in the electrocatalytic surface is provided by a surface film grown up from the film-forming metal base as a result of said halide agent attacking the film-forming metal base and said decomposed platinum-group metal compound is fully incorporated in said surface film grown up from the film-forming metal base whereby the electrocatalytic material formed from the decomposed platinum-group metal compound is an integral part of said surface film.