Experimental evidence of the interference between ionic and electronic flows in an oxide with prevailing electronic conduction
Abstract Linear transport theory prescribes that for, e.g. a binary oxide Co1−δO, a flow of cations (J1) may be induced not only by its direct cause which is a gradient of the cationic electrochemical potential (▿η1), but also indirectly by a gradient of the electronic electrochemical potential (▿η2), orJ1=−L11▿η1−L12▿η2,Lik being the transport coefficient. Routine practice, however, has been neglecting the cross coefficient, i.e. L12=0. We have determined experimentally the charge of transport of the cation α∗1 (≡ L 12 L 11 ) for Co1-δO with three different and independent techniques, and concluded that the cross coefficient is not negligible by any means. All the numerical data on α∗1 up to date are compiled. Consequences of the non-zero cross coefficient and the physico-chemical nature of the charge of transport are discussed.