TY - JOUR
T1 - Experimental and theoretical studies of hydrogen/deuterium spillover on Pt-loaded zeolite-templated carbon
AU - Nishihara, Hirotomo
AU - Ittisanronnachai, Somlak
AU - Itoi, Hiroyuki
AU - Li, Li Xiang
AU - Suzuki, Kimichi
AU - Nagashima, Umpei
AU - Ogawa, Hiroshi
AU - Kyotani, Takashi
AU - Ito, Masashi
PY - 2014/5/8
Y1 - 2014/5/8
N2 - Hydrogen storage in metal-doped carbons through a spillover mechanism has attracted a great attention. However, the data reported so far are lacking in consistency among different research groups, and the mechanism has not been fully revealed yet. In this work, we prepare a model Pt-loaded carbon by a simple and reproducible method in which already-synthesized Pt-nanocolloid is directly doped on zeolite-templated carbon. The Pt-loaded carbon thus obtained provides reliable data as for the temperature effects (273-353 K) on hydrogen/deuterium (H/D) adsorption isotherms, which contain the contributions of H2/D2 physisorption, H/D chemisorption on Pt surface, and H/D storage by the spillover mechanism. We extracted the last contribution (spillover H/D) from the isotherms, and found that the amount of the spillover H/D increases with increasing pressure (up to 100 kPa) and temperature (273-353 K). Detailed analysis of the number of H/D atoms stored by the spillover mechanism reveals that H/D radicals spilling from the Pt surface migrate on the carbon surface. The path integral molecular dynamics simulation also demonstrates the migration of atomic H/D on a model fragment of the zeolite-templated carbon, and suggests the enhancement of migration at higher temperature.
AB - Hydrogen storage in metal-doped carbons through a spillover mechanism has attracted a great attention. However, the data reported so far are lacking in consistency among different research groups, and the mechanism has not been fully revealed yet. In this work, we prepare a model Pt-loaded carbon by a simple and reproducible method in which already-synthesized Pt-nanocolloid is directly doped on zeolite-templated carbon. The Pt-loaded carbon thus obtained provides reliable data as for the temperature effects (273-353 K) on hydrogen/deuterium (H/D) adsorption isotherms, which contain the contributions of H2/D2 physisorption, H/D chemisorption on Pt surface, and H/D storage by the spillover mechanism. We extracted the last contribution (spillover H/D) from the isotherms, and found that the amount of the spillover H/D increases with increasing pressure (up to 100 kPa) and temperature (273-353 K). Detailed analysis of the number of H/D atoms stored by the spillover mechanism reveals that H/D radicals spilling from the Pt surface migrate on the carbon surface. The path integral molecular dynamics simulation also demonstrates the migration of atomic H/D on a model fragment of the zeolite-templated carbon, and suggests the enhancement of migration at higher temperature.
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U2 - 10.1021/jp5016802
DO - 10.1021/jp5016802
M3 - Article
AN - SCOPUS:84900436025
VL - 118
SP - 9551
EP - 9559
JO - Journal of Physical Chemistry C
JF - Journal of Physical Chemistry C
SN - 1932-7447
IS - 18
ER -