The thermotransport of H in 4N-purity Pd was studied by using a thermo-osmosis technique. A temperature gradient was maintained across the metal membrane, and each face was connected to a reservoir of solute gas. The

concentration of solute which dissolved in the membrane at each surface, and therefore the concentration gradient across the membrane, was obtained by measuring the solute gas pressures in the connecting reservoirs. The average heat of transport, for temperatures ranging from 400 to 560C, was 1.5kcal/g-atom. This value was essentially independent of the temperature, and that indicated a slight segregation of H to colder regions.

W.A.Oates, J.G.Shaw: Metallurgical Transactions, 1970, 1[11], 3237-8