Highlights •An amphipathic molecular layer is constructed on Zn surface to inhibit the zinc dendrites and side reactions.•The amphipathic molecular layer on Zn surface results in lower de-solvation energy barrier.•PAA can balance the interfacial electrostatic field on Zn surface and guide Zn ions to deposit uniformly.•The Zn/Zn symmetric cell acquires a cycle life of over 4600 h.