Biomineralization of ZrO2 nanoparticles on graphene oxide-supported peptide/cellulose binary nanofibrous membranes for high-performance removal of fluoride ions

Two-dimensional (2D) nanomaterial-based functional nanoporous membranes exhibit potential applications for economic, rapid, and highly efficient water purification. In order to improve the removal efficiency of various pollutants from water, it is necessary to introduce functional metal oxides into the 2D membranes to form hybrid membranes. In this work, we demonstrate the design and synthesis of graphene oxide (GO)-supported conjugation with cellulose nanofibers (CNFs) and self-assembled peptide nanofibers (PNFs). Ascribing to the biomimetic properties of both CNFs and PNFs, ZrO2 nanoparticles were synthesized along the as-formed binary nanofibers to form GO/PNF/CNF-ZrO2 nanohybrids via a biomineralization process. Through the vacuum filtration, nanofibrous membranes were fabricated easily, which exhibited high performance for the removal of fluoride ions (F-) from water. The removal efficiency of the designed hybrid membranes towards F- samples with the concentration range from 20 to 200 mg/L can exceed 96%. In addition, the nanofibrous filtration membranes showed good recyclability for continuous adsorption and removal of F-. The sustainability of the fabricated functional filtration membranes was further evaluated using the Sustainability Footprint method. This study will be valuable to promote the design and synthesis of nanoporous membranes via biomimetic synthesis with high sustainability for water purification applications.