XPS study of size effects of Fe3O4 nanoparticles on crosslinking degree of magnetic TFN membrane

The control of thin film nanocomposite (TFN) membranes cross-linking degree is an important factor to design new membranes and optimizing permeation characteristics. The Fe3O4 nanoparticle's based TFN membranes due to potentially added magnetic responsive properties to the membrane has a great importance in developing membrane architectures. Fe3O4/polyamide (PA) TFN membranes filled with nanoparticles in different sizes and concentrations have been synthesized. Cross-linking degree of PA layer characterized with Fourier transform spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) methods to evaluate size dependency of the cross-linking degree of PA layer network. Obvious correlations and competitions between concentration and size of nanoparticles which affect cross-linking degree have been developed. It has proven that with changing the size of the nanoparticles the concentration effects on polymerization and cross-linking can be tuned. Therefore optimization of size and concentration for fine tuning cross-linking degree in a proposed value is one of the consequences of this research. It concluded that size can be used as a powerful tool to design and engineer new and optimized membrane architectures.