Solid state NMR investigation of hydrous ruthenium oxide

Amorphous hydrous ruthenium oxide (RuO2.chiH(2)O) with different compositio n x has been studied using solid-state nuclear magnetic resonance (NMR) spe ctroscopy. The D-2 NMR spectra at different temperatures illustrate that th e water molecules undergo fast molecular motion even if the temperature is as low as 213 K. The static H-1 NMR spectra indicate the composition depend ent proton-proton dipolar interaction. It is demonstrated that the mobility of the water molecules and their interaction with ruthenium oxides play an important role in the proton charge density. In conclusion, the competitio n between these two antithetical effects provides a mechanism for the proto n charge storage of the RuO2 . chiH(2)O materials. (C) 2000 Elsevier Scienc e B.V. All rights reserved.