Pd–Pt alloys: correlation between electronic structure and hydrogenation properties

Abstract Palladium and its alloys have been extensively studied because of their faculty to store reversibly hydrogen isotopes. Here, the substitution of palladium with platinum is investigated. Thermodynamical studies have shown an anomalous behaviour regarding to the classical models. This original behaviour is explained by the study of the electronic structure of the binary solid solutions. The drastic decrease of the hydrogen solubility in the Pd–Pt alloys is accounted for by the filling up of the palladium conduction band by the valence electrons of platinum. The anomalous decrease of the stability of the hydride is explained by the large broadening of the valence band due to the substitution.