▎ 摘　　要

In this work, the authors expose transferred multilayer graphene on a yttrium based hydrogen sensor. Using spectroscopic ellipsometry, they show that graphene, as well as amorphous carbon reference films, reduce diffusion of hydrogen to the underlying Y layer. Graphene and C are both etched due to exposure to atomic H, eventually leading to hydrogenation of the Y to YH2 and YH3. Multilayer graphene, even with defects originating from manufacturing and transfer, showed a higher resistance against atomic H etching compared to amorphous carbon films of a similar thickness. Published by the AVS.