Alginate/PVA Polymer Electrolyte Membrane Modified by Hydrophilic Montmorillonite for Structure and Selectivity Enhancement for DMFC Application

Abstract

Nafion is a commercial membrane that is widely used in direct methanol fuel cells (DMFC) but has critical constraints such as being expensive and having high methanol crossover. Efforts to find alternative membranes are actively being carried out, including in this study, which looks at producing a Sodium Alginate/Poly (Vinyl Alcohol) (SA/PVA) blended membrane with modification by montmorillonite (MMT) as an inorganic filler. The content of MMT in SA/PVA-based membranes varied in the range of 2.0–20 wt% according to the solvent casting method implemented. The presence of MMT was seen to be most optimal at a content of 10 wt%, achieving the highest proton conductivity and the lowest methanol uptake of 9.38 mScm−1 and 89.28% at ambient temperature, respectively. The good thermal stability, optimum water absorption, and low methanol uptake of the SA/PVA-MMT membrane were achieved with the presence of MMT due to the strong electrostatic attraction between H+, H3O+, and −OH ions of the sodium alginate and PVA polymer matrices. The homogeneous dispersion of MMT at 10 wt% and the hydrophilic properties possessed by MMT contribute to an efficient proton transport channel in SA/PVA-MMT membranes. The increase in MMT content makes the membrane more hydrophilic. This shows that the loading of 10 wt% MMT is very helpful from the point of view of sufficient water intake to activate proton transfer. Thus, the membrane produced in this study has great potential as an alternative membrane with a much cheaper cost and competent future performance.

Influence of cesium bromide nanoparticles on the structural, optical, electrical, and antibacterial properties of polyvinyl alcohol/sodium alginate for biological applications

“…The broad peak observed at 2989–3638 cm −1 indicates the stretching of the OH groups existing in all films. The occurrence of a peak at 2912 cm −1 in the spectrum indicates stretching on the CH groups, affirming that all films are composed of hydrocarbons 36 . In the fingerprint region, there is a distinct alteration in peak intensity observed between 1300 and 1600 cm −1 , corresponding to COO − stretching, and 600–1200 cm −1 , involving CC, CO, and CH bending.…”

“…The occurrence of a peak at 2912 cm À1 in the spectrum indicates stretching on the C H groups, affirming that all films are composed of hydrocarbons. 36 In the fingerprint region, there is a distinct alteration in peak intensity observed between 1300 and 1600 cm À1 , corresponding to COO À stretching, and 600-1200 cm À1 , involving C C, C O, and C H bending. The noteworthy peaks and its respective wavenumbers are summarized in Table 2.…”

Enhanced proton conductivity and mechanical stability of crosslinked sodium alginate as a biopolymer electrolyte membrane in fuel cell application

“…Proton conductivity, = 𝐿 𝐴𝑅 (4) In this formula, L represents the thickness of the sample in cm, R stands for the membrane's resistance measured in Ohms, and A denotes the cross-sectional area of the membrane in cm 2 [13]. To ensure accuracy, this experiment was conducted three times to assess result reproducibility.…”