SPEEK-ZrP

Figure 5a displays spectra in the X-ray absorption near edge region given by sPEEK-ZrP samples after immersion in H3PO4 for periods of 10 min-... 

Fig. 6 Fourier transformed EXAFS spectra of sPEEK-ZrP membranes prepared by contact of ion-exchange membranes with H3PO4 (IM, 80 C) for 5 min (V) and 15h ( ), compared with that of well-crystallised a-ZrP prepared using the HE method ( )...

Fig. 7 Polarisation characteristics of sPEEK and sPEEK-ZrP (50 (Am) prepared by ion-exchange/precipitation with sPEEK membranes. The electrodes employed in these MEAs were standard ImgPtcm" E-TEK, Nafion dispersion was used at the mem-brane/electrode interface, and the cell was pressurised to 2.6barabs. sPEEK at 85 °C (A) sPEEK-ZrP at 85 °C ( ) and sPEEK-ZrP at 100°C ( )...

Fig. 10 Transmission electron micrograph of por-sPEEK-ZrP, pore diameter ca. 1-2 p.m. ZrP of thickness 30 nm coats the internal surfaces of the pores in an eggshell arrangement...

Fig. 16 Single fuel cell characterisation at 90-150°C of membrane electrode assemblies prepared using sPEEK-ZrP (20wt. % ZrP prepared in situ in sPEEK solution). Noncommercial electrodes, 1.2 mgcm PtRu anode, 1.2 mgcm Pt at cathode. 1 M methanol feed, 2.5 bar oxygen, 3 bar. Measurements at 90 °C, A lOO C, 110°C, 120 °C, 130 °C, A 140 °C, 150 °C. Unbroken line is current density vs. cell voltage dashed line is power density vs. cell voltage...

The in situ construction of the inorganic component within a cast polymer solution is not limited to metal oxides and in practice a range of other inorganic materials can be formed depending on the choice of precursor(s) incorporated in the polymer solution, and the nature of post-treatment following solvent removal. Roziere and Jones and co-workers have developed nano composite membranes in which zirconium phosphate is formed from zirconyl propionate introduced into a DMAc solution of sPEEK, by immersion of the cast film, after solvent removal, into phosphoric acid. This approach provides a robust synthetic route that can be generalised to other ionomers, and allows the amount of ZrP to be readily varied, even up to ca. 40-50 wt. %. 

SPEEK-inorganic (Si02, zirconium phosphate, and sulfenylphosphonate) nanocomposite PEMs are prepared either by infiltration of ZrOQ2, followed by reaction with phosphoric acid, or by blending of mesoporous ZrP/Si02 [60-64]. 

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