Z[lc]r-based hydrogen absorbing films prepared by ion beam assisted deposition

Abstract

Preparation of hydrogen absorbing thin films and evaluation of their hydrogen capacity are of great importance to develop multifunctional hydrogen absorbing composites. A linear relationship was found between the intensity of ERDA (Elastic Recoil Detection Analysis) spectrum and hydrogen content for palladium. ERDA is thus a useful tool to measure the hydrogen absorbing ability, of metallic material even when the equilibrium pressure of its hydride is higher than the vacuum pressure. Zr-based films with a Mn/Zr ratio of 4.1 were successfully prepared by ion beam assisted deposition and reversibly absorbed hydrogen to reach a H/Zr atomic ratio of 2 in the hydrogen-rich region of the film when hydrided at room temperature under 100 kPa of hydrogen. The surface became rich in manganese on hydriding and the zirconium species that might capture hydrogen atoms seemed to be confined by the manganese-rich layer.