A novel strategy for efficient removal of hazardous metal ions based on thermoresponsive phase separation of the PNIPAM/GO system

•The poly(N-isopropyl acrylamide) (PNIPAM)/graphene oxide (GO) mixed system gives temperature-responsive phase separation.•The phase separation produces a gel phase and a water phase.•Metal ions can be adsorbed on GO surface and then transferred into the gel phase.•The phase separation can achieve efficient removal of metal ions from polluted water in an extraction-like process.