The prospective ability of using thin Pd electroless films made of pure Pd and Pd-P alloys as hydrogen permeable anodes was evaluated by a comparative characterization of these materials. The morphology, structure and composition effect on their ability to adsorb and oxidize hydrogen in 0.1 M NaOH solution was investigated. The results revealed that pure Pd (prepared at low T) followed by Pd-P alloy (low P content) exhibit the highest activity to absorb and oxidize hydrogen. It was concluded that the Pd alloy amorphicity (brought by a low content of P) and the pure Pd core porosity (brought by a low deposition rate) are the main factors responsible for Such behaviour. In acid medium, it was found that Pd alloy films hinder the hydrogen absorption. (C) 2008 Elsevier Ltd. All Fights reserved.