Hydrogen adsorption on rhodium and copper-rhodium films

Hydrogen adsorption on the continuous-structure rhodium films with or without 0.34 copper monolayer is studied. Copper addition decreases the reversible and strong hydrogen adsorption and varies the temperature dependence of adsorption and desorption characteristics between 250 and 673 K. The results obtained suggest the blocking of adsorption centers of rhodium surface with copper. Centers of a new type, with enhanced rhodium-hydrogen bond energy, are found, which are formed via an electron redistribution within rhodium-copper clusters.