The surface compositions of the membranes were measured by X-ray photoelectron spectroscopy (XPS), using a Thermo Fisher Scientific ESCALAB 250 K-Alpha X-ray photoelectron spectrometer equipped with a monochromatic Al Kα X-ray source (1486.6 eV).
The surfacecompositions of the membranes were measured by X-ray photoelectronspectroscopy (XPS), using a Thermo Fisher ScientificESCALAB 250 K-Alpha X-ray photoelectron spectrometer equippedwith a monochromatic Al Kα X-ray source (1486.6 eV).