Determination of the hydrogen content in an evaporated Pd film by neutron interferometry

Abstract
We demonstrate the feasibility of a microneutron interferometer (MINI) to determine the hydrogen content in the evaporated palladium film. MINI consists of a thin palladium film sandwiched by two semitransparent multilayer mirrors of Ni/Ti. The atomic ratio H/Pd as obtained from the shift of the interference fringes, under hydrogen pressures of 1 and 2 atm, was found to be 0.43 and 0.55, respectively. The accuracy of the results is 5.5%. MINI realized a better determination of the atomic ratio H/Pd than that in the case of a single Pd film by obtaining high neutron reflectivity in a relatively high Q range.