Preparation of polydopamine-functionalized polyamidoxime membrane for uranium recovery from seawater

•PDA@PAO membranes were facilely produced via a simple two-step process.•PDA@PAO membranes have high adsorption capacity and selectivity in U-spiked natural seawater and simulated wastewater.•PDA@PAO membranes exhibited the characteristics of easy collection and distinct recycling ability.•A synergistic adsorption between the functional groups of amidoxime and PDA enhanced U(VI) capacity.