skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Effects of structure and size of Ni nanocatalysts on hydrogen selectivity via water-gas-shift reaction—A first-principles-based kinetic study

Authors:
; ; ; ORCiD logo
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1416654
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Catalysis Today
Additional Journal Information:
Journal Volume: 280; Journal Issue: P2; Related Information: CHORUS Timestamp: 2018-01-11 18:27:48; Journal ID: ISSN 0920-5861
Publisher:
Elsevier
Country of Publication:
Netherlands
Language:
English

Citation Formats

Zhou, Mingxia, Le, Thong Nguyen-Minh, Huynh, Lam K., and Liu, Bin. Effects of structure and size of Ni nanocatalysts on hydrogen selectivity via water-gas-shift reaction—A first-principles-based kinetic study. Netherlands: N. p., 2017. Web. doi:10.1016/j.cattod.2016.07.018.
Zhou, Mingxia, Le, Thong Nguyen-Minh, Huynh, Lam K., & Liu, Bin. Effects of structure and size of Ni nanocatalysts on hydrogen selectivity via water-gas-shift reaction—A first-principles-based kinetic study. Netherlands. doi:10.1016/j.cattod.2016.07.018.
Zhou, Mingxia, Le, Thong Nguyen-Minh, Huynh, Lam K., and Liu, Bin. Wed . "Effects of structure and size of Ni nanocatalysts on hydrogen selectivity via water-gas-shift reaction—A first-principles-based kinetic study". Netherlands. doi:10.1016/j.cattod.2016.07.018.
@article{osti_1416654,
title = {Effects of structure and size of Ni nanocatalysts on hydrogen selectivity via water-gas-shift reaction—A first-principles-based kinetic study},
author = {Zhou, Mingxia and Le, Thong Nguyen-Minh and Huynh, Lam K. and Liu, Bin},
abstractNote = {},
doi = {10.1016/j.cattod.2016.07.018},
journal = {Catalysis Today},
number = P2,
volume = 280,
place = {Netherlands},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.cattod.2016.07.018

Citation Metrics:
Cited by: 5works
Citation information provided by
Web of Science

Save / Share:
  • The diffusion of dilute hydrogen in fcc Ni–Al and Ni–Fe binary alloys was examined using kinetic Monte Carlo method with input kinetic parameters obtained from first-principles density functional theory. The simulation involves the implementation of computationally efficient energy barrier model that describes the configuration dependence of the hydrogen hopping. The predicted hydrogen diffusion coefficients in Ni and Ni 89.4Fe 10.6 are compared well with the available experimental data. In Ni–Al, the model predicts lower hydrogen diffusivity compared to that in Ni. Overall, diffusion prefactors and the effective activation energies of H in Ni–Fe and Ni–Al are concentration dependent of themore » alloying element. Furthermore, the changes in their values are the results of the short-range order (nearest-neighbor) effect on the interstitial diffusion of hydrogen in fcc Ni-based alloys.« less
  • The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. We present a microkinetic model as well as experimental data for the low-temperature water gas shift (WGS) reaction catalyzed by Pt at temperatures from 523 to 573 K and for various gas compositions at a pressure of 1 atm. Thermodynamic and kinetic parameters for the model are derived from periodic, self-consistent density functional theory (DFT-GGA) calculations on Pt(111). The destabilizingmore » effect of high CO surface coverage on the binding energies of surface species is quantified through DFT calculations and accounted for in the microkinetic model. Deviations of specific fitted model parameters from DFT calculated parameters on Pt(111) point to the possible role of steps/defects in this reaction. Our model predicts reaction rates and reaction orders in good agreement with our experiments. The calculated and experimental apparent activation energies are 67.8 kJ/mol and 71.4 kJ/mol, respectively. The model shows that the most significant reaction channel proceeds via a carboxyl (COOH) intermediate. Formate (HCOO), which has been experimentally observed and thought to be the key WGS intermediate in the literature, is shown to act only as a spectator species.« less
  • The water-gas shift reaction (WGS, CO + H₂O → CO₂) was studied over CuO/CeO₂ catalysts with two different ceria particle morphohologies, in the form of nanospheres (ns) and nanocubes (nc). To understand the strong dependence of the WGS reaction activity on the ceria nanoshapes, pulses of CO (without and with water vapor) were employed during in situ X-ray diffraction (XRD) and X-ray absoprtion near edge structure (XANES) measurements done to characterize the catalysts. The results showed that CuO/CeO₂ (ns) exhibited a substantially better activity than CuO/CeO₂ (nc). The higher activity was associated with the unique properties of CuO/CeO₂ (ns), suchmore » as the easier reduction of highly dispersed CuO to metallic Cu, the stability of metallic Cu and a larger concentration Ce³⁺ in CeO₂ (ns).« less