The invention concerns a substrate that is electrical conductive on at least one of the faces of same, provided with a stack of thin layers comprising at least one layer of catalyst material suitable for accelerating the growth of carbon nanotubes, characterized in that the stack comprises the sequence of thin layers deposited in the following order on top of said at least one electrically conductive face of the substrate: a) optionally, a metal made from metal M or a layer of a metal alloy made from metal M or a graphene layer; b) a titanium layer (Ti); c) an aluminum layer (Al); d) a layer of catalyst material(s) for the growth of carbon nanotubes. The invention also concerns a functional substrate (6) comprising a substrate coated with a carbon nanotube (NTC) mat, a production method and the uses of such a functional substrate.