Stability and hydrogenation of "bare" gadolinium nanoparticles

Gadolinium nanoparticles, deposited via an inert gas evaporation method, show improved stability towards oxidation and it is therefore possible to carry out an ex-situ investigation on "bare" Gd nanoparticles, i.e., in the absence of a protective Pd layer, for the first time. A size-induced structural transformation from hexagonal close packing to the higher-symmetry face-centered cubic structure is observed. The important observation of hydrogen-Gd-nanoparticle interaction at room temperature and atmospheric pressure, without a Pd catalytic layer, makes Gd nanoparticles a potential candidate for hydrogen-sensing, switching, and storage applications.