Nano-scale study of polymeric nanofilters

A nano-scale characterization of polyethersulfone nanofiltration membranes (NF-PES-10), both as received and after employing in an aqueous solution nanofiltration process for 72h, is presented. The surface of polyethersulfone (PES) membranes was studied by horizontal attenuated total reflection Fourier transform IR spectroscopy (HATR-FTIR) to investigate the functional groups and by atomic force microscope (AFM) to measure topographical characteristics. We also performed scanning near-field optical microscopy (SNOM) experiments to correlate the morphology and the local nanoscopic reflectance capability of the membrane surface.