Quantification of water states in thin proton exchange membrane manufacturing using terahertz time-domain spectroscopy

Water states in proton exchange membranes have previously been extracted using terahertz time-domain spectroscopy (THz-TDS) for thick Nafion membranes. In this work, we have developed a parametric based algorithm for data analysis and applied it to thin industrially relevant membranes (13-70μm), processed under different conditions, producing results consistent with conventional gravimetric analysis and prior demonstrations. This therefore opens up opportunities for rapid membrane investigations and understanding

Evaluation of water states in thin proton exchange membrane manufacturing using terahertz time-domain spectroscopy

Perfluorinated sulfonic-acid ionomers are the most common proton exchange membrane material whose structure underpins their unique water and chemical/mechanical stability properties. Understanding this performance-stability trade-offs is therefore vital for realising optimal membranes. Terahertz time-domain spectroscopy has been demonstrated to resolve molecular water states and retention properties inside thick Nafion membranes. By developing a parametric-based algorithm for data analysis, we demonstrate the broad applicability of this technique to industrially relevant thin ionomers (13–70 μm) prepared under various processing conditions where results are supported by conventional gravimetric analysis and prior demonstrations. Using this technique therefore opens up opportunities for rapid future parameter space investigation for membrane optimisation