M. Caldararu et al., THE ELECTRICAL AND CATALYTIC PROPERTIES OF YBA2CU3O7-X FOR OXIDATION REACTIONS BELOW 400 DEGREES-C, Journal of Materials Science, 32(11), 1997, pp. 2895-2902
The a.c. electrical and catalytic properties of YBa2Cu3O7-x have been
investigated by in situ dynamic experiments. The data indicate a stron
g dependence of surface conduction on chemisorbed spec ies which, if l
oosely bound, cause fluctuations. Proton-donating compounds produce an
increase in conductivity and an oscillating behaviour. Fluctuations c
an also be associated with instability of the basic matrix at low temp
eratures in various atmospheres, and may explain the somewhat erratic
catalytic properties of this material. In particular, the presence of
water may lead to blocking of some adsorption-active catalytic sites.