Method For Monitoring A Process For Powder-Bed Based Additive Manufacturing Of A Component And Such A System

Abstract

A gas diffusion electrode and electrolysis cells containing gas diffusion electrodes are provided. The gas diffusion electrodes include a copper-containing carrier, and first and second layers. The first layer comprising at least copper and at least one binder having hydrophilic and hydrophobic pores. The second layer comprising copper and at least one binder. The second layer present atop the carrier and the first layer atop the second layer, wherein the content of binder in the first layer is less than the binder in the second layer.

What is claimed is: 
     
         1 . A gas diffusion electrode comprising:
 a copper-containing carrier, and   a first layer comprising at least copper and at least one binder, the first layer comprising hydrophilic and hydrophobic pores,   a second layer comprising copper and at least one binder, the second layer present atop the carrier and the first layer atop the second layer, wherein the content of binder in the first layer is less than the binder in the second layer, and wherein the second layer comprises 3-30% by weight of binder, and the first layer comprises 0-10% by weight of binder.   
     
     
         2 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer does not comprise charcoal-based and/or carbon black-based fillers. 
     
     
         3 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer does not comprise surface-active substances. 
     
     
         4 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises at least 40 at % of copper, based on the layer. 
     
     
         5 . The gas diffusion electrode as claimed in  claim 1 , wherein the copper-containing carrier is a copper mesh. 
     
     
         6 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises at least one metal oxide having a lower reduction potential than the evolution of ethylene selected from the group consisting of ZrO 2 , Al 2 O 3 , CeO 2 , Ce 2 O 3 , ZnO 2 , and MgO. 
     
     
         7 . The gas diffusion electrode as claimed in  claim 1 , wherein the second layer partly penetrates the first layer. 
     
     
         8 . A process for producing a gas diffusion electrode, comprising:
 producing a first mixture comprising at least copper and optionally at least one binder,   producing a second mixture comprising at least copper and at least one binder,   applying the second mixture comprising at least copper and at least one binder to a copper-containing carrier, in the form of a sheetlike structure,   applying the first mixture comprising at least copper and optionally at least one binder to the second mixture, and   dry rolling the first and second mixtures onto the carrier to form at least first and second layers,   wherein the proportion of binder in the second mixture is 3-30% by weight of binder, based on the second mixture, and wherein the proportion of binder in the first mixture is 0-10% by weight, based on the first mixture, where the content of binder in the first mixture is smaller than in the second mixture.   
     
     
         9 . The process as claimed in  claim 8 , wherein the copper-containing carrier comprises a copper mesh having a mesh size w of 0.3 mm<w<2.0 mm and a wire diameter x of 0.05 mm<x<0.5 mm. 
     
     
         10 . The process as claimed in  claim 8 , wherein the bed height y of the first mixture on the carrier is in the range of 0.3 mm<y<2.0 mm. 
     
     
         11 . The process as claimed in  claim 8 , wherein the gap width in the rolling application H 0  is the height of the carrier +40% to 50% of the total bed height Hf of the first mixture. 
     
     
         12 . The process as claimed in  claim 8 , wherein the rolling is effected by a calender. 
     
     
         13 . The process as claimed in  claim 8 , wherein the copper content in the mixture is at least 40 at % of copper, based on the mixture. 
     
     
         14 . The process as claimed in  claim 8 , wherein the mixture further comprises
 at least one metal oxide having a lower reduction potential than the evolution of ethylene including at least one of ZrO 2 , Al 2 O 3 , CeO 2 , Ce 2 O 3 , ZnO 2 , and MgO.   
     
     
         15 . An electrolysis cell comprising a gas diffusion electrode as claimed in  claim 1 . 
     
     
         16 . The gas diffusion electrode as claimed in  claim 1 , wherein the second layer comprises 10-30% by weight binder and the first layer comprises 0.1-10% by weight binder. 
     
     
         17 . The gas diffusion electrode as claimed in  claim 1 , wherein the second layer comprises 10-20% by weight binder and the first layer comprises 1-10% by weight binder. 
     
     
         18 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises 1-7% by weight binder. 
     
     
         19 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises 3-7% by weight binder. 
     
     
         20 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises at least one copper-rich intermetallic phase selected from the group of systems consisting of Cu—Al, Cu—Zr, Cu—Y, Cu—Hf, CuCe, Cu—Mg, Cu—Y—Al, Cu—Hf—Al, Cu—Zr—Al, Cu—Al—Mg, Cu—Al—Ce with copper contents >60 at %. 
     
     
         21 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises one or more of copper-containing perovskites, defect perovskites, and perovskite-related compounds. 
     
     
         22 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises YBa 2 Cu 3 O 7  where 0≤δ≤1. 
     
     
         23 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises a compound selected from the group consisting of CaCu 3 Ti 4 O 12 , La 1.85 Sr 0.15 CuO 3.930 Cl 0.053 , and (La,Sr) 2 CuO 4 . 
     
     
         24 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises at least 50 at % of copper, based on the layer. 
     
     
         25 . The gas diffusion electrode as claimed in  claim 1 , wherein the first layer comprises at least 60 at % of copper, based on the layer. 
     
     
         26 . The process as claimed in  claim 8 , wherein the copper-containing carrier comprises a copper mesh having a mesh size w of 0.5 mm<w<1.0 mm and a wire diameter x of 0.1 mm×x≤0.25 mm. 
     
     
         27 . The process as claimed in  claim 8 , wherein the bed height y of the first mixture on the carrier is in the range of 0.5 mm≤y≤1.0 mm. 
     
     
         28 . The process as claimed in  claim 8 , wherein the mixture further comprises at least one copper-rich intermetallic phase selected from the group of the systems consisting of Cu—Al, Cu—Zr, Cu—Y, Cu—Hf, CuCe, Cu—Mg, Cu—Y—Al, Cu—Hf—Al, Cu—Zr—Al, Cu—Al—Mg, and Cu—Al—Ce with copper contents >60 at %. 
     
     
         29 . The process as claimed in  claim 8 , wherein the mixture further comprises at least one metal for formation of a copper-rich metallic phase selected from the group consisting of Al, Zr, Y, Hf, Ce, Mg, Y—Al, Hf—Al, Zr—Al, Al—Mg, and Al—Ce, such that the copper content is >60 at %. 
     
     
         30 . The process as claimed in  claim 8 , wherein the mixture further comprises at least one of copper-containing perovskites, defect perovskites, and perovskite-related compounds. 
     
     
         31 . The process as claimed in  claim 8 , wherein the mixture further comprises YBa 2 Cu 3 O 7-δ  where 0≤δ≤1. 
     
     
         32 . The process as claimed in  claim 8 , wherein the mixture further comprises at least one of CaCu 3 Ti 4 O 12 , La 1.85 Sr 0.15 CuO 3.930 Cl 0.053 , and (La,Sr) 2 CuO 4 .