Title
Characterization and hydrogen sorption behaviorsof FeNiCr-carbon composites derived from Fe, Niand Cr-containing polyacrylonitrile fibers preparedby electrospinning method
Author
Takehiro Kaneko, Yasuhiro Watanuki, Takeshi Toyama, Yoshiyuki Kojima, Nobuyuki Nishimiya
Year
2017
Journal
International Journal of Hydrogen Energy
Abstract
In order to enhance hydrogen storage capacity of carbonaceous materials through metal
modification, FeNiCr-carbon composites were prepared by calcination of Fe, Ni and Crcontaining
polyacrylonitrile (PAN) fibers fabricated by electrospinning method. Fe (III), Ni
(II) and Cr (III) acetylacetonates (M (acac)n) were selected as metal sources. Increase of
specific surface area and formation of micropores were observed on heat decomposition of
M (acac)n particularly through introduction of steam. Maximal hydrogen content, 1.62 mass
%, was obtained at 77 K under 0.8 MPa of hydrogen for a FeNiCr-carbon composite, which
contained about 15.5 mass% of metals and had specific surface area of 501 m2 g 1. The
hydrogen content exceeded the hydrogen physisorption limit, 2.34 mass% per 1000 m2 g 1,
which was calculated on the basis of the commensurateeincommensurate transition with
an enhancing factor r of 1.126. After hydrogenation at 653 K, no hydrogen desorption peaks
were observed for FeNiCr powders derived from M (acac)n, and one peak at 828 K for a
carbonaceous sample prepared from unmodified PAN fibers. From the most promising
FeNiCr-carbon composite, another peak was recorded at 752 K in addition to the peak at
828 K. The former would be originated from hydrogen on novel sorption sites additionally
created on the composite formation.
Instrument
NRS-4100
Keywords
Raman imaging microscopy, Electrospinning method, Carbon, FeNiCr-carbon composite, Hydrogen storage material, PAN fiber