Electrode and method for production
An electrode for an electrochemical reaction bath has a base body, an active side which is configured to come into contact with the reaction bath, and a passive side which is configured to come into contact with at least one electrical conductor. The passive side includes a doped carbon coating that is preferably less than 5 μm in thickness. Preferably the doped carbon coating is a doped polycrystalline diamond coating in sp 3 configuration and is doped with boron.
1 . A method for producing an electrode, comprising:
forming a base body comprising silicon to comprise
an active side configured to come into contact with a reaction bath, and
a passive side configured to come into contact with at least one conductor; then
coating the active side of the base body with a doped diamond coating;
then
cleaning a surface of the passive side of the base body by
grinding the surface of the passive side, and
etching the surface of the passive side; and then
coating the surface of the passive side with a doped carbon coating, wherein an electrode is produced with the doped diamond coating on the active side and the doped carbon coating on the passive side, wherein the doped carbon coating has sufficient electrical conductivity to permit current to operate the electrode, wherein the doped carbon coating is 1 μm to 5 μm thick.
2 . The method according to claim 1 wherein at least some of the silicon of the base body is ground during the cleaning.
3 . The method according to claim 1 wherein the surface of the passive side is subjected to the etching after the grinding.
4 . The method according to claim 3 wherein the etching is performed with one or more of potassium hydroxide and hydrofluoric acid.
5 . The method according to claim 1 wherein the cleaning of the surface of the passive side comprises at least one gas phase etching step.
6 . The method according to claim 5 wherein the at least one gas phase etching step comprises exposure of the surface of the passive side to a hydrogen (H 2 ) gas.
7 . The method according to claim 1 wherein the doped carbon coating is less than 2 μm thick.
8 . The method according to claim 1 wherein the surface of the passive side exhibits a surface roughness of 0.2 μm<R a <0.6 μm prior to coating with the doped carbon coating and/or of R z <10 μm and/or R a <1.0 μm after coating with the doped carbon coating.
9 . The method according to claim 1 wherein the doped carbon coating is a doped polycrystalline diamond coating in sp 3 configuration.
10 . The method according to claim 1 wherein coating the active side is performed by chemical vapor deposition.