Effect of Ni-TMA MOF/GO on hydrogen storage properties of MgH2

In this work, graphene oxide (GO) was integrated into the established synthesis route of Ni-TMA MOF. The results demonstrate that the resulting Ni-TMA MOF/GO shows pronounced catalytic activity toward the hydrogen sorption behavior of MgH 2 . Morphological characterization indicates that the as-prepared Ni-TMA MOF/GO possesses a dandelion-like microspherical architecture, featuring an overall spherical profile and a hierarchically porous interior with abundant voids. This structural configuration provides enlarged specific surface area and a high density of accessible active sites. Among all investigated composites, MgH 2 -3 wt.% Ni-TMA MOF/GO delivers the best overall hydrogen-storage performance. At 573 K under 2.6 MPa H 2 , it reaches a maximum hydrogen uptake of 6.3 wt%. The composite also exhibits rapid absorption kinetics, taking up 6.0 wt% H 2 within 1 min. In addition, it maintains good cycling durability: after 100 hydrogenation/dehydrogenation cycles, the reversible capacity remains 5.8 wt%.