The effect of ZIF-8 nanoparticle concentration on microwave-assisted synthesis of poly (vinyl alcohol)-co-acrylic acid copolymeric membranes and their potential application in fuel cell

Copolymeric membranes were created by microwave-assisted synthesis of poly (vinyl alcohol) (PVA) and acrylic acid (AA) using a one-step polymerization technique using potassium persulfate (KPS) as an initiator, culminating in the creation of PVA-co-AA. Furthermore, zeolitic imidazolate framework-8 (ZIF-8) nanoparticles (NPs) were generated using the sol–gel method, and the ZIF-8 NPs were integrated in situ to the manufactured PVA-co-AA copolymers to form the PVA-co-AA-ZIF-8 nanocomposite. In the final composite membrane, ZIF-8 and copolymer served as a filler and adsorbent, respectively. The fabrication circumstances, such as the percent composition, the amount of copolymer and ZIF-8 added to the polymer solution, were studied. The gas permeability of the PVA-co-AAm/ZIF-8 nanocomposite membranes was investigated, altering the ZIF-8 content as a filler, i.e., 1, 2.5, 5, and 10 wt.%. All of the copolymeric nanocomposite membranes were cross-linked with tetra ethyl orthosilicate (TEOS). The membranes were subjected to FTIR measurement to validate the copolymerization reaction. A scanning electron microscopy (SEM) technique was used to examine the surface morphology and cross-sections of the produced membranes. The thermal stability of the produced membranes was evaluated using thermogravimetric analysis (TGA). The membranes were tested for usage in fuel cells. When the amount of ZIF-8 in the membranes grew, so did their ionic exchange capacity and, as a result, proton conductivity. The introduction of a little amount of ZIF-8 as a filler increased the membrane’s efficiency in terms of proton conductivity qualities. The membranes showed a low H₂ concentration and a good proton conductivity (10^-2 S cm^-1).