Porous Ni nanofibers (NFs) were synthesized via a single-nozzle electrospinning technique with subsequent calcination and reduction. The as-prepared continuous Ni NFs, with a uniform diameter of ∼50 nm and porous structure composed of a myriad of Ni nanocrystallites, were adopted to catalyze MgH
2. The homogeneous distribution of Ni nanoparticles (NPs), obtained by ball milling Ni NFs with MgH 2, on the surface of MgH 2offered effective catalytic sites to significantly enhance the hydrogen storage properties of MgH 2. In particular, 4% Ni NF catalyzed MgH 2(MgH 2-4% Ni NFs) starts to release hydrogen at only 143 °C, with a peak temperature of 244 °C, 157 °C and 96 °C lower than for MgH 2catalyzed with as-milled 4% Ni powders (MgH 2-4% Ni powders), and it dehydrogenates completely within only 11 min at 325 °C (7.02 wt%). Compared with plain MgH 2and MgH 2-4% Ni powders, the activation energy of the as-milled MgH 2-4% Ni NF composite is significantly decreased to 81.5 kJ mol-1.