Bimetallic NiCo functional graphene: an efficient catalyst for hydrogen-storage properties of MgH₂

Ying Wang; Guang Liu; Cuihua An; Li Li; Fangyuan Qiu; Yijing Wang; Lifang Jiao; Huatang Yuan

doi:10.1002/asia.201402245

Bimetallic NiCo functional graphene: an efficient catalyst for hydrogen-storage properties of MgH₂

Chem Asian J. 2014 Sep;9(9):2576-83. doi: 10.1002/asia.201402245. Epub 2014 Jul 8.

Authors

Ying Wang¹, Guang Liu, Cuihua An, Li Li, Fangyuan Qiu, Yijing Wang, Lifang Jiao, Huatang Yuan

Affiliation

¹ Collaborative Innovation Center of Chemistry and Chemical Engineering of Tianjin, Key Laboratory of Advanced Energy Materials Chemistry (MOE), Institute of New Energy Material Chemistry, Tianjin Key Lab on Metal and Molecule-Based Material Chemistry, Nankai University, Tianjin, 30007 (P.R. China), Fax: (+86) 22-23503639.

PMID: 25044774
DOI: 10.1002/asia.201402245

Abstract

Bimetallic NiCo functional graphene (NiCo/rGO) was synthesized by a facile one-pot method. During the coreduction process, the as-synthesized ultrafine NiCo nanoparticles (NPs), with a typical size of 4-6 nm, were uniformly anchored onto the surface of reduced graphene oxide (rGO). The NiCo bimetal-supported graphene was found to be more efficient than their single metals. Synergetic catalysis of NiCo NPs and rGO was confirmed, which can significantly improve the hydrogen-storage properties of MgH2. The apparent activation energy (E(a)) of the MgH2-NiCo/rGO sample decreases to 105 kJ mol(-1), which is 40.7% lower than that of pure MgH2. More importantly, the as-prepared MgH2-NiCo/rGO sample can absorb 5.5 and 6.1 wt% hydrogen within 100 and 350 s, respectively, at 300 °C under 0.9 MPa H2 pressure. Further cyclic kinetics investigation indicates that MgH2-NiCo/rGO nanocomposites have excellent cycle stability.

Keywords: graphene; hydrogen storage; magnesium; nanoparticles; supported catalysts.