Investigation on sturdy centipede-configured PVDF based proton exchange membrane for water electrolysis

This study outlines an approach for investigating centipede-type structured PVDF oxy-tethered-styrene sulfonic acid (O-PVDF-t-SSA) proton exchange membranes, emphasizing their applicability in proton exchange membrane (PEM) water electrolysis. PEMs were fabricated using different weight percentages of PVDF to SSA, encompassing 15, 20 and 25 w/w % (of SSA). The PEMs were assessed using a universal testing machine (UTM) and thermogravimetric (TGA) analysis, confirming their mechanical and thermal stability respectively. A dense structure with closely packed ionic channels was confirmed with surface and phase morphology using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Performance assessment of PEMs in a water electrolyzer configuration was conducted in a two-compartment cell at 80°C, employing Nafion-117 membrane for comparison. This elucidated that the O-PVDF-t-SSA-25 membrane demonstrated a reduced potential value of 1.64 V at 200 mA cm-2, in contrast to the state-of-art Nafion-117 (1.72 V) at the same current density. Results suggest that integration of an O-PVDF-t-SSA-based membrane into the electrolysis cell shows potential for shrinking the overall cost of the electrolyzer while concurrently yielding high-purity hydrogen.