Interface-covalent coupled zeolite–graphene oxide membranes via NaOH-induced in situ crystallization for robust radionuclide adsorption

Abstract

The development of adsorptive membranes that combine high radionuclide removal efficiency with structural and radiation stability remains a major hurdle in aqueous separation materials. Herein, we present a novel interface-engineering strategy to fabricate covalently crosslinked zeolite–graphene oxide (GO) membranes. Specifically, NaOH-mediated in situ crystallization of EMT-type zeolite precursors within GO nanosheet assemblies concurrently induces formation of Si–O–C covalent linkages, thereby integrating the inorganic and carbon components at the molecular interface. The resulting membrane manifests a stabilized layered architecture, expanded interlayer spacing, and enhanced ion-accessible active sites while retaining GO's hydrophilicity. It exhibits high adsorption capacities toward Cs⁺ (199.0–224.4 mg g⁻¹) and Sr²⁺ (290.6–302.8 mg g⁻¹) ions, sustained operation across a wide pH range, and superior durability under γ-irradiation.