TY - JOUR
T1 - Combined hydrogen production and storage with subsequent carbon crystallization
AU - Lueking, Angela D.
AU - Gutierrez, Humberto R.
AU - Fonseca, Dania A.
AU - Narayanan, Deepa L.
AU - Van Essendelft, Dirk
AU - Jain, Puja
AU - Clifford, Caroline E.B.
PY - 2006/6/21
Y1 - 2006/6/21
N2 - We provide evidence of low-temperature hydrogen evolution and possible hydrogen trapping in an anthracite coal derivative, formed via reactive ball milling with cyclohexene. No molecular hydrogen is added to the process. Raman-active molecular hydrogen vibrations are apparent in samples at atmospheric conditions (300 K, 1 bar) for samples prepared 1 year previously and stored in ambient air. Hydrogen evolves slowly at room temperature and is accelerated upon sample heating, with a first increase in hydrogen evolution occurring at approximately 60 °C. Subsequent chemical modification leads to the observation of crystalline carbons, including nanocrystalline diamond surrounded by graphene ribbons, other sp2-sp3 transition regions, purely graphitic regions, and a previously unidentified crystalline carbon form surrounded by amorphous carbon. The combined evidence for hydrogen trapping and carbon crystallization suggests hydrogen-induced crystallization of the amorphous carbon materials, as metastable hydrogenated carbons formed via the high-energy milling process rearrange into more thermodynamically stable carbon forms and molecular hydrogen.
AB - We provide evidence of low-temperature hydrogen evolution and possible hydrogen trapping in an anthracite coal derivative, formed via reactive ball milling with cyclohexene. No molecular hydrogen is added to the process. Raman-active molecular hydrogen vibrations are apparent in samples at atmospheric conditions (300 K, 1 bar) for samples prepared 1 year previously and stored in ambient air. Hydrogen evolves slowly at room temperature and is accelerated upon sample heating, with a first increase in hydrogen evolution occurring at approximately 60 °C. Subsequent chemical modification leads to the observation of crystalline carbons, including nanocrystalline diamond surrounded by graphene ribbons, other sp2-sp3 transition regions, purely graphitic regions, and a previously unidentified crystalline carbon form surrounded by amorphous carbon. The combined evidence for hydrogen trapping and carbon crystallization suggests hydrogen-induced crystallization of the amorphous carbon materials, as metastable hydrogenated carbons formed via the high-energy milling process rearrange into more thermodynamically stable carbon forms and molecular hydrogen.
UR - http://www.scopus.com/inward/record.url?scp=33745338123&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33745338123&partnerID=8YFLogxK
U2 - 10.1021/ja0604818
DO - 10.1021/ja0604818
M3 - Article
C2 - 16771488
AN - SCOPUS:33745338123
SN - 0002-7863
VL - 128
SP - 7758
EP - 7760
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 24
ER -