Facile fabrication method of nanocomposite pore filling ion exchange membrane: Impregnation method using dispersion solution of inorganic particles

Abstract

Research on composite ion exchange membranes (IEMs) focuses on compensating the limitations of homogenous IEMs. The fabrication of nanocomposite IEMs is relatively complex, as the dispersion of inorganic substances within a polymer matrix must be considered. In this study, we propose a simple method for preparing nanocomposite IEMs by combining a porous substrate and dispersion solution with inorganic nanoparticles. The nanocomposite porous substrate with nanoparticles is prepared by impregnating a solution into a porous substrate, where the nanoparticles penetrate the nanosized pores of the substrates by capillary forces. Subsequently, nanocomposite pore-filling IEMs (PIEMs) are fabricated by impregnating an electrolyte solution into the substrate and photopolymerization. Impregnation applies to the manufacture of nanocomposite PIEMs, regardless of the type, surface conditions, and size of inorganic particles in dispersion. Through the sequential impregnation of dispersion solutions, single- and multi-component PIEMs containing more than one type of nanoparticle are manufactured. The increased interconnectivity of ion conduction channels in PIEMs by nanoparticles causes permselectivity improvement in nanocomposite PIEMs. However, compared to PIEMs without inorganic particles, the addition of inorganic particles results in a lower electrolyte polymer content in the PIEMs, leading to deterioration of the ion exchange capacity and resistance of nanocomposite PIEMs.