Graphene-wrapped reversible reaction for advanced hydrogen storage

Abstract

X. (2016). Graphene-wrapped reversible reaction for advanced hydrogen storage. Nano Energy, 26 488-495. Graphene-wrapped reversible reaction for advanced hydrogen storage AbstractHere, we report the fabrication of a graphene-wrapped nanostructured reactive hydride composite, i.e., 2LiBH4-MgH2, made by adopting graphene-supported MgH2 nanoparticles (NPs) as the nanoreactor and heterogeneous nucleation sites. The porous structure, uniform distribution of MgH2 NPs, and the steric confinement by flexible graphene induced a homogeneous distribution of 2LiBH4-MgH2 nanocomposite on graphene with extremely high loading capacity (80 wt%) and energy density. The well-defined structural features, including even distribution, uniform particle size, excellent thermal stability, and robust architecture endow this composite with significant improvements in its hydrogen storage performance. For instance, at a temperature as low as 350 °C, a reversible storage capacity of up to 8.9 wt% H2, without degradation after 25 complete cycles, was achieved for the 2LiBH4-MgH2 anchored on graphene. The design of this threedimensional architecture can offer a new concept for obtaining high performance materials in the energy storage field. AbstractHere, we report the fabrication of a graphene-wrapped nanostructured reactive hydride composite, i.e., 2LiBH4-MgH2, made by adopting graphene-supported MgH2 nanoparticles (NPs) as the nanoreactor and heterogeneous nucleation sites. The porous structure, uniform distribution of MgH2 NPs, and the steric confinement by flexible graphene induced a homogeneous distribution of 2LiBH4-MgH2 nanocomposite on graphene with extremely high loading capacity (80 wt%) and energy density. The well-defined structural features, including even distribution, uniform particle size, excellent thermal stability, and robust architecture endow this composite with significant improvements in its hydrogen storage performance. For instance, at a temperature as low as 350 o C, a reversible storage capacity of up to 8.9wt.% H2, without degradation after 25 complete cycles, was achieved for the 2LiBH 4 -MgH 2 anchored on graphene. The design of this three-dimensional architecture can offer a new concept for obtaining high performance materials in the energy storage field.

Effect of LaNi3 Amorphous Alloy Nanopowders on the Performance and Hydrogen Storage Properties of MgH2

“…However, it is significantly better than MgH2/10 wt% metallic glassy Ti2Ni (87.3 kJ/mol) 37 , MgH2/5 wt% TiMn2 (117 kJ/mol) 42 , and MgH2/5.3 wt% TiC (97.74 kJ/mol) 42 systems. Contrary to this, Ea of the present system is above those reported values for, MgH2/14 wt% TiAl (65 kJ/mol) 43 and MgH2/5 wt% quasicrystal-AlCuFe (64.25 kJ/mol) 40 systems.…”

“…This value was drastically decreased to 73.26 kJ/mol upon increasing the rod milling time to 100 h, as indexed in Figure 8b. The Ea value of this system is closed to previously reported value of MgH2 powders doped with 10 wt% Fe nanoparticles (86 kJ/mol) 38 , 4 wt% Ni nanofibers (81 kJ/mol) 39 , 10 wt% Cu nanoparticles (76 kJ/mol) 40 , MgH2/5 wt% metallic glassy Zr70Ni20Pd10 (51 kJ/mol) 35 and 20 wt% Ti0.4Cr0.15Mn0.15 V0.3 (71 kJ/mol) 41 systems. However, it is significantly better than MgH2/10 wt% metallic glassy Ti2Ni (87.3 kJ/mol) 37 , MgH2/5 wt% TiMn2 (117 kJ/mol) 42 , and MgH2/5.3 wt% TiC (97.74 kJ/mol) 42 systems.…”

Tuning LiBH4 for Hydrogen Storage: Destabilization, Additive, and Nanoconfinement Approaches

“…We observed an improved wetting of the matrix when graphene was present, in accordance with the insertion of boron within graphene defects as presented by Mason [115]. The solvothermal reaction of organometallic compounds (MgBu 2 , LiBu) under high hydrogen pressure (35, 50 bar) allowed Xia et al to decorate graphene sheets with nanostructured hydrides [134,135]. 10 nm core-shell MgH 2 -LiBH 4 nanoparticles and 2 nm thick LiBH 4 layers were observed by TEM at the surface of the graphene support, even at very high weight loading (70-80%).…”

“…10 nm core-shell MgH 2 -LiBH 4 nanoparticles and 2 nm thick LiBH 4 layers were observed by TEM at the surface of the graphene support, even at very high weight loading (70-80%). This allowed both composites to exhibit excellent hydrogen capacity (9.1-12.8 wt.%), and the reactive hydride [134] displayed much-improved reversibility in front of the lone LiBH 4 [135]. These materials present well-defined peaks by XRD, suggesting the hydride might not be nanoconfined.…”

Mechanically-Induced Catalyzation of MgH2 Powders with Zr2Ni-Ball Milling Media

“…Apart from the mechanical treatment approach, catalyzation MgH 2 powders with proper volume fractions of catalytic agents [21], including pure metals [22], intermetallic compounds [23][24][25][26], metal-oxides [27,28], metal/metal oxide composites [5,29], -carbides [30,31], metallic glassy alloys [32][33][34] and chlorides [35] have shown outstanding effects on enhancing the hydrogen storage properties of MgH 2 and infer its apparent activation energy of decomposition [36]. More recently, self-assembled MgH 2 and metal borohydride nanoparticles on graphene technique has shown great enhancement of the behavior of the metal hydride phase [37][38][39].…”