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Title: Lattice Matched Carbide–Phosphide Composites with Superior Electrocatalytic Activity and Stability

Abstract

Composites of electrocatalytically active transition-metal compounds present an intriguing opportunity toward enhanced activity and stability. Here, to identify potentially scalable pairs of a catalytically active family of compounds, we demonstrate that phosphides of iron, nickel, and cobalt can be deposited on molybdenum carbide to generate nanocrystalline heterostructures. Composites synthesized via solvothermal decomposition of metal acetylacetonate salts in the presence of highly dispersed carbide nanoparticles show hydrogen evolution activities comparable to those of state-of-the-art non-noble metal catalysts. Investigation of the spent catalyst using high resolution microscopy and elemental analysis reveals that formation of carbide–phosphide composite prevents catalyst dissolution in acid electrolyte. Lattice mismatch between the two constituent electrocatalysts can be used to rationally improve electrochemical stability. Among the composites of iron, nickel, and cobalt phosphide, iron phosphide displays the lowest degree of lattice mismatch with molybdenum carbide and shows optimal electrochemical stability. Turnover rates of the composites are higher than that of the carbide substrate and compare favorably to other electrocatalysts based on earth-abundant elements. Lastly, our findings will inspire further investigation into composite nanocrystalline electrocatalysts that use molybdenum carbide as a stable catalyst support.

Authors:
ORCiD logo [1];  [2]; ORCiD logo [3]; ORCiD logo [4]; ORCiD logo [4];  [5];  [6]; ORCiD logo [1]; ORCiD logo [1]
  1. Univ. of Tennessee, Knoxville, TN (United States). Center for Renewable Carbon
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States). Bredesen Center for Interdisciplinary Research and Education
  3. Stanford Univ., CA (United States). Dept. of Chemical Engineering
  4. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
  5. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical and Biomolecular Engineering
  6. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemical and Biomolecular Engineering; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States). Bredesen Center for Interdisciplinary Research and Education
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Nuclear Energy (NE)
OSTI Identifier:
1410911
Grant/Contract Number:
AC05-00OR22725; NE0000693
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Chemistry of Materials
Additional Journal Information:
Journal Volume: 29; Journal Issue: 21; Journal ID: ISSN 0897-4756
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Carbide; phosphide; electrocatalysis; hydrogen evolution reaction; composite materials

Citation Formats

Regmi, Yagya N., Roy, Asa, King, Laurie A., Cullen, David A., Meyer, Harry M., Goenaga, Gabriel A., Zawodzinski, Thomas A., Labbé, Nicole, and Chmely, Stephen C.. Lattice Matched Carbide–Phosphide Composites with Superior Electrocatalytic Activity and Stability. United States: N. p., 2017. Web. doi:10.1021/acs.chemmater.7b03377.
Regmi, Yagya N., Roy, Asa, King, Laurie A., Cullen, David A., Meyer, Harry M., Goenaga, Gabriel A., Zawodzinski, Thomas A., Labbé, Nicole, & Chmely, Stephen C.. Lattice Matched Carbide–Phosphide Composites with Superior Electrocatalytic Activity and Stability. United States. doi:10.1021/acs.chemmater.7b03377.
Regmi, Yagya N., Roy, Asa, King, Laurie A., Cullen, David A., Meyer, Harry M., Goenaga, Gabriel A., Zawodzinski, Thomas A., Labbé, Nicole, and Chmely, Stephen C.. 2017. "Lattice Matched Carbide–Phosphide Composites with Superior Electrocatalytic Activity and Stability". United States. doi:10.1021/acs.chemmater.7b03377.
@article{osti_1410911,
title = {Lattice Matched Carbide–Phosphide Composites with Superior Electrocatalytic Activity and Stability},
author = {Regmi, Yagya N. and Roy, Asa and King, Laurie A. and Cullen, David A. and Meyer, Harry M. and Goenaga, Gabriel A. and Zawodzinski, Thomas A. and Labbé, Nicole and Chmely, Stephen C.},
abstractNote = {Composites of electrocatalytically active transition-metal compounds present an intriguing opportunity toward enhanced activity and stability. Here, to identify potentially scalable pairs of a catalytically active family of compounds, we demonstrate that phosphides of iron, nickel, and cobalt can be deposited on molybdenum carbide to generate nanocrystalline heterostructures. Composites synthesized via solvothermal decomposition of metal acetylacetonate salts in the presence of highly dispersed carbide nanoparticles show hydrogen evolution activities comparable to those of state-of-the-art non-noble metal catalysts. Investigation of the spent catalyst using high resolution microscopy and elemental analysis reveals that formation of carbide–phosphide composite prevents catalyst dissolution in acid electrolyte. Lattice mismatch between the two constituent electrocatalysts can be used to rationally improve electrochemical stability. Among the composites of iron, nickel, and cobalt phosphide, iron phosphide displays the lowest degree of lattice mismatch with molybdenum carbide and shows optimal electrochemical stability. Turnover rates of the composites are higher than that of the carbide substrate and compare favorably to other electrocatalysts based on earth-abundant elements. Lastly, our findings will inspire further investigation into composite nanocrystalline electrocatalysts that use molybdenum carbide as a stable catalyst support.},
doi = {10.1021/acs.chemmater.7b03377},
journal = {Chemistry of Materials},
number = 21,
volume = 29,
place = {United States},
year = 2017,
month =
}

Journal Article:
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