High proton mobility in hydrogenated yttrium-barium cuprate with both normal and increased oxygen content (H2m + hBa2YCu3O6.5m + d'm = 0; 1; 2, h≥ O, d ≤ 1)
Abstract The two-step procedure for preparing yttrium-barium cuprates described by the general formula H 2m + h Ba 2 YCu 3 O 6.5 + m+d' ( m = 0; 1; 2, h ≥ O , d ≤ l ), is considered. The kinetic of hydrogen charging Ba 2 YCu 3 O 7 and the oxidation of hydrogenated samples is described. The proton migration in the bulk and hydrogen exchange with a gaseous phase have been studied by the isotope exchange method. The diffusion coefficient of hydrogen at 470 K is estimated to be 10 − 8 cm 2 s − 1