In situ formed ultrafine metallic Ni from nickel (II) acetylacetonate precursor to realize an exceptional hydrogen storage performance of MgH2Ni-EG nanocomposite

It has been well known that doping nano-scale catalysts can significantly improve both the kinetics and reversible hydrogen storage capacity of MgH2. However, so far it is still a challenge to directly synthesize ultrafine (e.g., < 5 nm), mainly because complicated chemical reaction processes. Here, facile one-step high-energy ball milling process developed in situ form Ni nanoparticles from nickel acetylacetonate precursor MgH2 matrix. With combined action metallic expanded graphite (EG), formed MgH2Ni-EG nanocomposite with optimized amounts EG release 7.03 wt.% H2 within 8.5 min at 300 °C after 10 cycles. At temperature close room (50 °C), also absorb 2.42 1 h be confirmed microstructural characterization analysis transformed into Mg2Ni/Mg2NiH4 subsequent absorption desorption calculated dehydrogenation activation energy reduced obviously comparison pure Our work provides methodology performance by combining uniformly dispersed catalyst EG.