Cannabinol is a mildly psychoactive cannabinoid that binds to the cannabinoid receptors with more selectivity for CB2 over CB1 found in trace amounts in cannabis. CBN is mostly found in aged and stored, and is derived from the plant’s main psychoactive chemical, tetrahydrocannabinol. Wikipedia

CBN can be understood as a weaker version of THC. When THC components found in the cannabis plant age, they break down
Put simply, there’s no evidence in the literature that CBN will affect sleep in humans or animals on its own.
Can you vape CBN?
The convenience of CBN in a vape cartridge product is highly appealing. A few puffs of a CBN enhanced vape pen, and the user experiences the effects immediately, opposed to the 30-60 minute onset of an edible.