High temperature H-1 NMR study of proton conducting oxide SrCe0.95Y0.05H0.004O3-delta

The ionic motion of protons in yttrium doped SrCeO3, perovskite has been in vestigated by means of high temperature H-1 NMR and ac electric conductivit y measurements. The temperature dependences of line shapes and spin-lattice relaxation times (T-1,) were obtained. The inverse temperature versus loga rithm of T-1, plot shows asymmetric temperature dependence with respect to its minimum value, and was well interpreted using the classical Bloembergen , Purcell and Pound (BPP) formula with introducing distributions of the act ivation energies. The averaged correlation times of the proton hopping were obtained from the T-1, data. The conductivity calculated from the Einstein equation using NMR correlation times assuming the jump distance of proton hopping as 1 Angstrom yields quantitative agreement with the measured condu ctivity in a wide temperature range. (C) 1999 Elsevier Science B.V. All rig hts reserved.