Hydrogen Uptake of Platinum-Doped Graphite Nanofibers and Stochastic Analysis of Hydrogen Spillover
Graphite nanofibers (GNFs) were doped with platinum in an attempt to activate the materials for moderate temperature hydrogen adsorption. Characterization of the 1% Pt/GNF sample indicates well-dispersed, metallic platinum particles ranging from 2 to 5 nm in diameter. At 27 °C and 20 bar, the hydrogen uptake of 1% Pt/GNF was less than 0.1 wt % and showed no increase relative to the GNF precursor within experimental detection limits. To explore this apparent anomaly, a stochastic Monte Carlo simulation was used to analyze the hydrogen spillover process for idealized two-dimensional surfaces with two surface types with interfacial mass transfer from the first to the second surface site. The model suggests interfacial mass transfer may not improve overall surface coverage when the rates of adsorption and desorption to the support are comparable. Dimensionless groupings are introduced to the stochastic simulation to explore the conditions in which interfacial transfer will lead to significant surface coverage from a catalytically active surface to a previously inert surface. The implications for hydrogen storage are discussed..
P. Jain et al., "Hydrogen Uptake of Platinum-Doped Graphite Nanofibers and Stochastic Analysis of Hydrogen Spillover," Journal of Physical Chemistry C, vol. 111, no. 4, pp. 1788-1800, American Chemical Society (ACS), Jan 2007.
The definitive version is available at https://doi.org/10.1021/jp0654922
Chemical and Biochemical Engineering
Pennsylvania State University.Department of Energy & Geo-Environmental EngineeringPennsylvania State University.College of Earth and Mineral SciencePennsylvania State.Institutes for the Environment & Pennsylvania State University.Wilson Initiation Grant
Keywords and Phrases
Dimensionless groupings; Graphite nanofibers (GNFs); Hydrogen spillover; Interfacial mass transfer; Computer simulation; Graphite fibers; Hydrogen; Monte Carlo methods; Platinum; Semiconductor doping; Stochastic control systems; Two dimensional; Nanostructured materials
International Standard Serial Number (ISSN)
Article - Journal
© 2007 American Chemical Society (ACS), All rights reserved.