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Crystal shape controlled H₂ storage rate in nanoporous carbon composite with ultra-fine Pt nanoparticle.

ABSTRACT: This study demonstrates that the hydrogen storage rate (HSR) of nanoporous carbon supported platinum nanocatalysts (NC) is determined by their heterojunction and geometric configurations. The present NC is synthesized in an average particle size of ~1.5 nm by incipient wetness impregnation of Pt⁴⁺ at carbon support followed by annealing in H² ambient at 102-105 °C. Among the steps in hydrogen storage, decomposition of H₂ molecule into 2 H atoms on Pt NC surface is the deciding factor in HSR that is controlled by the thickness of Pt NC. For the best condition, HSR of Pt NC in 1~2 atomic layers thick (4.7 μg/g min) is 2.6 times faster than that (1.3 μg/g min) of Pt NC with higher than 3 atomic layers thick.

SUBMITTER: Chen TY

PROVIDER: S-EPMC5307954 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Crystal shape controlled H2 storage rate in nanoporous carbon composite with ultra-fine Pt nanoparticle.

Chen Tsan-Yao TY Zhang Yanhui Y Hsu Liang-Ching LC Hu Alice A Zhuang Yu Y Fan Chia-Ming CM Wang Cheng-Yu CY Chung Tsui-Yun TY Tsao Cheng-Si CS Chuang Haw-Yeu HY

Scientific reports 20170214

This study demonstrates that the hydrogen storage rate (HSR) of nanoporous carbon supported platinum nanocatalysts (NC) is determined by their heterojunction and geometric configurations. The present NC is synthesized in an average particle size of ~1.5 nm by incipient wetness impregnation of Pt4+ at carbon support followed by annealing in H2 ambient at 102-105 °C. Among the steps in hydrogen storage, decomposition of H2 molecule into 2 H atoms on Pt NC surface i ...[more]

PMID: 28195224

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