Fourier transform infrared (FTIR) spectroscopy was used to investigate the gas-solid interactions of dimethyl methylphosphonate (DMMP) with metal oxide surfaces. The surface species is bound to the surface through the P=0 bond. On titanium dioxide based powders, this bond could not be unambiguously seen. A correlation has been established between the labilization of the P=0 bond by chemisorption and the electronegativity of the cations. The adsorption is a slow activated process.

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The hydration process of cationic membrane protogenic groups was investigated using in situ ATR-FTIR spectroscopy. The aim of this study is to provide a relationship between the hydration degree of the membrane and the dissociation state of exchange sites inside the polymer material. IR spectra were recorded by means of an environmental device specifically manufactured to allow the control of water vapour pressure in equilibrium with the sample. The behaviour of Nafion 112 and sulfonated poly(ether ether ketone) (S-PEEK), in both proton and sodium forms, was compared. IR data, analyzed and fitted in the 800-1850 cm(-1) spectral range, gave precise information on the assignment of sulfonic group vibrational modes. The results of this study improve the understanding of the transition phenomena between dissociated and undissociated states of the grafted sites in protonic conductors.

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