Theoretical Investigation of Hydrogen Adsorption and Hydrogen Spillover on Graphene Monolayer-Supported Single Transitional Metal Atoms

Graphene-based nanostructures loaded with transitional metallic atoms have been identified as promising materials for hydrogen storage. In this study, we investigate the adsorption and spillover of hydrogen on a single transitional metal atom incorporated graphene (TM-Gr) through density functional theory (DFT) calculations. Specifically, we explore the geometric and electronic properties of 20 different TM-Gr structures. Our findings reveal that Y-Gr and Sc-Gr exhibit the most favorable H atom adsorption, while Mn-Gr and Cr-Gr are more suitable for H spillover. Additionally, feature importance analysis highlights that Bader charge accumulated in H atom, C-H bond length, and work function of TM-Gr are the three most important features that are sensitive to the activation energy of H spillover. Overall, this work provides valuable insights for the screening of new materials for hydrogen storage.