Process for producing an electrode with a noble metal catalyst for alkaline water electrolysis

Abstract

A method for producing an electrode (4) with a noble metal catalyst for alkaline water electrolysis is specified. The method comprises (S1) providing the electrode substrate (1), (S2) providing a matrix material (2) and a catalyst material (3) as starting materials for the coating, (S3) mixing the matrix material (2) and the catalyst material (3), and (S4) coating the substrate (1) with the mixture of matrix material (2) and catalyst material (3) by means of high-velocity flame spraying (HVOF). Furthermore, a correspondingly produced electrode (4), an electrochemical cell (10) comprising this electrode, and an electrolyzer (20) are specified.

Claims

[1] A method for producing an electrode (4) with a noble metal catalyst for alkaline water electrolysis, comprising the following steps: - (S1) providing the electrode substrate (1), - (S2) providing a matrix material (2) and a catalyst material (3) as starting materials for the coating, - (S3) mixing the matrix material (2) and the catalyst material (3), and - (S4) Coating the substrate (1) with the mixture of matrix material (2) and catalyst material (3) by high velocity flame spraying (HVOF). [2] Method according to claim 1, wherein a metal fiber fleece, a metal foam, a metal mesh, or an expanded metal is used as the electrode substrate (1). [3] Method according to claim 1 or 2, wherein the matrix material (2) is in powder form and is mixed in weight proportions between 10% and 20% with a noble metal powder as catalyst material (3). [4] Method according to one of the preceding claims, wherein the matrix material (2) is a nickel aluminide, in particular Ni3Al. [5] Method according to one of the preceding claims, wherein the catalyst material (3) is in powder form and has a primary particle size of 3 µm to 10 µm. [6] Method according to one of the preceding claims, wherein the catalyst material (3) comprises nanoparticles of Pt, Ru, Ni, Rh, Re, and / or Pd. [7] Method according to one of the preceding claims, wherein the catalyst material (3) provided on a cathode of a corresponding electrochemical cell (10), such as an alkaline electrolysis cell, comprises so-called "Ptblack", a "RuPt"-black and / or "Ru"-black. [8] Method according to one of the preceding claims, wherein the substrate (1) is preheated to above 180°C, in particular about 200°C. [9] Electrode (4) which is produced according to the method according to one of the preceding claims, wherein the electrode (4) is distinguished - compared to known electrodes - by an improved mechanical strength as well as by an increased porosity, wherein a surface loading of the electrode surface with precious metal is in particular less than 30 mg / cm 2 amounts. [10] Electrochemical cell (10) with an electrode (4) according to claim 9. [11] Electrolyzer (20) comprising an electrochemical cell (10) according to claim 10.

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