Composite sPEEK-TPyP membranes development for portable applications

Composite membranes based on sulphonated Polyetheretherketone (sPEEK) and 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP) were developed for portable applications. A sulphonation degree of 65% and different loadings (0-5wt%) of TPyP porphyrin were used. Spectroscopic studies (UV-Vis and fluorescence emission), ionic exchange capacity, water uptake, structural and morphological analyses were carried out. A good interaction between the filler and the polymer was found, probably due to specific supramolecular interactions among the nitrogenous atoms present in the periphery of the porphyrin ring and sulphonic groups of polymer. The membrane with the lowest loading (~1wt%) of TPyP, shows slightly lower water uptake and unaltered ? values than the reference membrane, resulting in quite unaltered proton conductivity also in anhydrous conditions. Electrochemical tests were performed in a PEFC 25cm² single cell at room temperature and anhydrous hydrogen/humidified air. A power density of 93mW/cm² was found in anhydrous conditions for sample with the lowest loading of TPyP.