▎ 摘　　要

As suggested in our previous study, graphene containing Ni-based coating possessed a lower diffusion coefficient of hydrogen that pure Ni did. In this study, Pure Ni and Ni-graphene coatings were prepared in the Watts' bath by electrodeposition, moreover, the enhancing mechanism of graphene on hydrogen permeation resistance of Ni coating was discussed for the first time. By means of various characterization techniques such as EBSD, SEM and TEM, it was revealed that both the refinement of grain size and the increase of special grain boundaries (GBs) fraction played the main roles due to the introduction of graphene into Ni deposits. (C) 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.