Brockmann 1

Acryloyl chloride (>97%, Sigma-Aldrich (Munich, Germany), contained 400 ppm phenothiazine as stabilizer, stored at 4 °C), anhydrous dichloromethane (DCM) (99.9%, extra dry, Acros Organics (Geel, Belgium)), 4,4′-azobis(4-cyanovaleric acid) (ACVA) (>98%, Sigma-Aldrich, stored at 4 °C), 2-(dodecylthiocarbonothioylthio)propionic acid (DTPA) (97%, Sigma-Aldrich, stored at 4 °C) and N,N-dimethylformamide (DMF) (>99.5%, VWR Chemicals (Darmstadt, Germany)) were used as received. Pyrrolidine (>99%, Acros Organics) and piperidine (99%, Acros Organics) were stored at 4 °C over molecular sieves (mesh size = 4 Å). Styrene (99%, Grüssing (Filsum, Germany), stored at 4 °C) and N,N-dimethylacrylamide (DMA) (99%, Sigma-Aldrich, stored at 4 °C) were freshly percolated through a column of basic alumina (>98%, Brockmann I, Sigma-Aldrich) prior to use to remove the inhibitor methyl ether hydroquinone. DOX (99%, Grüssing) was stored over KOH pellets (>85%, Merck (Darmstadt, Germany)) and freshly percolated through a basic alumina column prior to use to remove peroxides. Ultrapure water (MilliQ quality, resistivity >18.2 MΩ·cm⁻¹) was obtained from a Millipore (Darmstadt, Germany) MilliQ water purification system. All other chemicals were used as received in at least analytical grade.

The substances such as di-n-butyl itaconate (DBI), lauryl methacrylate (LMA), itaconic acid (IA), sodium dodecyl sulfate (SDS) surfactant, potassium persulfate (KPS) initiator, and hydroquinone (HQ) inhibitor were acquired from Sigma-Aldrich (Saint Louis, MO, USA). In addition, ethanol, petroleum ether, sodium hydroxide (NaOH), and ammonia (28 wt % in H₂O) were obtained from Fermont (Monterrey, Nuevo Leon, Mexico). The degree of purity of the above substances was of reagent grade. Deionized water (DI-H₂O) was used throughout the investigation. Tetrahydrofuran (THF, HPLC grade from JT Baker (Phillipsburg, NJ, USA)) solvent was used in the polymer characterization. Argon gas (Praxair, Danbury, CT, USA) was used to purge the reactor. Cellulose extraction thimbles (Whatman^™, Marlborough, MA, USA) were used in gel content measurements. DBI and LMA were purified prior to polymerization, passing them through an inhibitor removal column of basic alumina or Brockmann I (Sigma-Aldrich, Saint Louis, MO, USA). SDS was purified by Soxhlet extraction with petroleum ether for 24 h, followed by recrystallization with absolute ethanol. All other chemicals were used as supplied.

Graphene oxide water dispersions (4 mg/mL) were purchased from Graphenea (Cambridge, MA, USA). Alumina powder (activated, neutral, Brockmann I, Sigma Aldrich, Burlington, MA, USA), aluminum chloride hexahydrate (ReagentPlus, 99%, Sigma Aldrich, Burlington, MA, USA), Aluminum (Al) foil (0.024 cm thick, Puratronic, 99.997% purity, Alfa Aesar, Haverhill, MA, USA) were used as Al³⁺ sources. All the reagents were used as received without further purification. Solutions of the GO sheets and 0.5 mmol of the Al-containing species were prepared by simply dissolving the Al³⁺ sources in the GO solutions followed by 4 weeks of stirring. Free-standing GO and AGO membranes were obtained by an ambient evaporation drying process (21^°C, humidity of 50~60%) in a Teflon evaporating dish. The entire drying process took about 5 days to obtain a membrane with an average thickness of 12 ± 2 µm as measured by a thickness gauge (DeFelsko, PosiTector 6000, Ogdensburg, NY, USA).