A sealing device for sealing a first side against a second side of a machine part, wherein the sealing device has a sealing element which contacts a counter element. At least a part of the sealing element and/or at least a part of the counter element is coated with a layer consisting of or containing fullerene-like carbon nitride (FL-CNx), wherein an inter-layer of chromium (Cr) or aluminum (Al) or molybdenum (Mo) or titanium (Ti) or tungsten (W) or a diamond-like coating (DLC) or a metal-mix diamond-like coating (Me-DLC) is arranged between the surface of the sealing element and the layer consisting of or containing fullerene-like carbon nitride and/or between the surface of the counter element and the layer consisting of or containing fullerene-like carbon nitride.