Magnetic Coat Hooks
So, not all of these are exactly coat hooks, there are a few coat knobs and pegs, too. However, they are all magnetic and rather extremely so. These are not standard magnetic coat hooks; these are rather robust.
All these magnetic coat hooks have a heavy duty weight capacity of 12 pounds. Heavy duty means your coat isn't going to slowly slide down the wall over the course of the day.
Heavy duty magnetic coat hangers are not very common, but there are a few here for your consideration.
One final note: Most of these units have matching non-magnetic versions for wall or door attachment, so you can mix and match as your design requires.