Process for the preparation of self-supporting, self-cleaning open-cell metal foams containing at least one of the following transition metals: Ag, Au, Co, Ni, Cr, Cu, Fe, Ir, Mn, Mo, Nb, Os, Pd, Pt, Re, Rh, Ru, Ta, Tc, W, and/or at least one of the following non-metals: Ge, Sb, Si, comprising that i) a polyurethane composite foam is prepared from the liquid components A and B being of a polyurethane foam and from the particle suspension of at least one of transition metal oxide and/or at least one of non-metal oxide, where A is a polyol, and B is a diisocyanate or its derivative, and the particle suspension of at least one of transition metal oxide and/or at least one of non-metal oxide is a) mixed with the mixture of the liquid components A and B, or b) mixed with liquid component A and then liquid component B is added, or c) mixed with liquid component B and then liquid component A is added, or d) mixed separately with liquid component A and liquid component B, and the resulting mixtures are then mixed with each other, and ii) the thus obtained polyurethane, and optionally an additional source of elemental carbon like graphite or graphite powder, is subjected to to a stepwise heat treatment in vacuum in the presence of a least a stoichiometric amount of elemental carbon in an amount sufficient to fix the oxygen present in the reactor, wherein the organic material is first decomposed, and the metal and/or non-metal oxide particles are reduced, in the presence of elemental carbon at a temperature below the melting point of the metal and/or non-metal particles, and then by further increasing the temperature for sintering the metal and/or non-metal particles thus gradually increasing the mechanical stability of the metal or non-metal foam, iii) optionally the obtained metal foam is subjected to heat treatment in the air or in an oxygen-containing medium for cleaning it from carbon contamination, and the resulting transition metal oxide or non-metal oxide is then reduced by heat treatment in vacuum, in the presence of the amount of elemental carbon necessary to fix the oxygen present in the reactor, at a temperature below the melting point of the transition metal oxide or non-metal oxide, and iv) optionally the metal on the surface of the foam may be exchanged by treatment with the solution of a metal which is more electropositive than the transition metal or non-metal constructing the metal foam. i) a polyurethane composite foam is prepared from the liquid components A and B being of a polyurethane foam and from the particle suspension of at least one of transition metal oxide and/or at least one of non-metal oxide, where A is a polyol, and B is a diisocyanate or its derivative, and the particle suspension of at least one of transition metal oxide and/or at least one of non-metal oxide is a) mixed with the mixture of the liquid components A and B, or b) mixed with liquid component A and then liquid component B is added, or c) mixed with liquid component B and then liquid component A is added, or d) mixed separately with liquid component A and liquid component B, and the resulting mixtures are then mixed with each other, and a) mixed with the mixture of the liquid components A and B, or b) mixed with liquid component A and then liquid component B is added, or c) mixed with liquid component B and then liquid component A is added, or d) mixed separately with liquid component A and liquid component B, and the resulting mixtures are then mixed with each other, and ii) the thus obtained polyurethane, and optionally an additional source of elemental carbon like graphite or graphite powder, is subjected to to a stepwise heat treatment in vacuum in the presence of a least a stoichiometric amount of elemental carbon in an amount sufficient to fix the oxygen present in the reactor, wherein the organic material is first decomposed, and the metal and/or non-metal oxide particles are reduced, in the presence of elemental carbon at a temperature below the melting point of the metal and/or non-metal particles, and then by further increasing the temperature for sintering the metal and/or non-metal particles thus gradually increasing the mechanical stability of the metal or non-metal foam, iii) optionally the obtained metal foam is subjected to heat treatment in the air or in an oxygen-containing medium for cleaning it from carbon contamination, and the resulting transition metal oxide or non-metal oxide is then reduced by heat treatment in vacuum, in the presence of the amount of elemental carbon necessary to fix the oxygen present in the reactor, at a temperature below the melting point of the transition metal oxide or non-metal oxide, and iv) optionally the metal on the surface of the foam may be exchanged by treatment with the solution of a metal which is more electropositive than the transition metal or non-metal constructing the metal foam.