Premium
Cost‐Effective Hierarchical Catalysts for Promoting Hydrogen Release from Complex Hydrides
Author(s) -
Yang ChengHsien,
Hsu ChihPing,
Lee ShengLong,
Wang KuanWen,
Chang JengKuei
Publication year - 2015
Publication title -
chemsuschem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.412
H-Index - 157
eISSN - 1864-564X
pISSN - 1864-5631
DOI - 10.1002/cssc.201500413
Subject(s) - dehydrogenation , catalysis , supercritical fluid , chemical engineering , carbon nanotube , hydrogen , hydride , nanoparticle , materials science , hydrogen storage , nanotechnology , synchrotron , chemistry , organic chemistry , physics , nuclear physics , engineering
Abstract Fe nanoparticles (∼10 nm), used to grow carbon nanotubes (CNTs), have an outstanding ability to catalyze the dehydrogenation of LiAlH 4 . The CNTs help connect Fe and LiAlH 4 and create microchannels among the composite, thus promoting the release of hydrogen. Inspired by these results, a supercritical‐CO 2 ‐fluid‐assisted deposition technique is employed to decorate the Fe/CNTs with highly dispersed nanosized Ni (∼2 nm in diameter) for better performance. With the incorporation of 10 wt % of this hierarchical catalyst (Ni/Fe/CNTs), the initial dehydrogenation temperature of LiAlH 4 is decreased from ∼135 to ∼40 °C. At 100 °C, this catalyzed LiAlH 4 takes only ∼0.1 h to release 4.5 wt % hydrogen, which is more than 100 times faster than the time needed with pristine LiAlH 4 . The dehydrogenation mechanism of the complex hydride is examined using in situ synchrotron X‐ray diffraction.