The present invention provides an organic light emitting diode, characterized in that it has the following layers, each on top of the preceding one: - optionally a down conversion phosphor layer, - a substrate, - optionally a hole injecting layer, - a non-emissive hole transporting layer which is crosslinked, - a non-crosslinked emissive layer consisting of electron and hole transporting hosts doped with electron blue phosphorescent emitters, - an electron transporting layer, - a cathode layer. It further provides a method of preparation of such diode and materials for such diode.