NOVELTY - Producing (P1) a surface-modified carbon-comprising support, involves: mixing a carbon-comprising support with at least one metal compound, a carbon- and/or nitrogen-comprising organic substance, and optionally a dispersion medium; optionally evaporating the dispersion medium at 40-200 degrees C; and heating a resulting mixture to 500-1200 degrees C to form at least one selected from metal carbide, metal nitride, metal oxycarbide, metal oxynitride, metal carboxynitride and metal carbonitride on the carbon-comprising support.    USE - For producing surface-modified carbon-comprising support, particularly a material comprising carbide, nitride, oxycarbide, oxynitride, carboxynitride and carbonitride-functionalized carbon. The support is useful as a catalytically active metal in electrochemical cells, particularly fuel cells, electrolysis cells or batteries; and as a catalyst, a corrosion-resistant filler in electrodes, or as support for a catalytically active metal (claimed).    ADVANTAGE - The process modifies the surface of the carbon-comprising support. This modification leads to an increase in the corrosion stability of the support. As a result of the metal carbides, metal nitrides, metal oxynitrides, metal carboxides, metal carboxynitrides and/or metal carbonitrides produced in heating step, the carbon is bound to the surface of the support and no longer undergoes any reaction with the oxygen surrounding the support. Thus, corrosion of the carbon-comprising support can be reduced and even avoided completely. As a result of the use of carbon- and/or nitrogen-comprising substance in mixing step, the reaction proceeds quantitatively even at temperatures lower than in the prior art and can be applied to various transition metals. Due to the lower temperature, the carbides, nitrides, carbonitrides, carboxides, oxynitrides and/or carboxynitrides are more finely divided, have a higher BET surface area (preferably 30-1000 m2/g) and are more catalytically active. Compared to finely divided unsupported carbides, nitrides, carbonitrides, carboxides, oxynitrides and/or carboxynitrides, the carbon-supported carbides, nitrides, carbonitrides, carboxides, oxynitrides and/or carboxynitrides produced are more sintering and oxidation stable than unsupported compounds of this type. In contrast to known processes in which a metal carbide layer is produced on the carbon-comprising support, the present process makes it possible to produce a larger number of compounds, e.g. various metal carbides or metal nitrides and also mixed phases derived from it.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a surface-modified carbon-comprising support produced by the process (P1).