HYBRID MULTIFUNCTIONAL SPONGES FOR ADSORPTION AND DEGRADATION OF POLLUTANTS

The design of new hybrid nanocomposites based on poly (2-hydroxyethylmethacrylate) (pHEMA) graphene oxide (GO) cryo-sponges, wherein ZnO nanolayers have been deposited to impart them photocatalytic properties, is here reported. Atomic layer deposition (ALD) at low temperature is specifically selected as deposition technique to stable anchor ZnO molecules to the pendant polymer OH groups. Furthermore, to boost the PHEMA cryo-gel adsorption capability versus organic dyes, GO is added during the synthetic procedure. The morphology, the crystallinity, and the chemical composition of the samples were deeply investigated by scanning electron microscopy (SEM), X-ray diffraction analyses (XRD), Fourier transform infrared spectroscopy (FTIR) as well as thermogravimetric analysis (TGA). Swelling properties and adsorption kinetics models of the hybrid materials were also evaluated. Finally, the adsorption and photocatalytic performance were tested and compared for all samples by using methylene blue (MB) as simulant dye. Particularly, the adsorption efficiency of ZnO PHEMA and ZnO PHEMA GO nanocomposites, as well as they in situ regeneration via photocatalysis, render such devices very appealing for advanced wastewater treatment technology.