skip to main content

DOE PAGESDOE PAGES

This content will become publicly available on May 19, 2017

Title: Role of chemical composition in the enhanced catalytic activity of Pt-based alloyed ultrathin nanowires for the hydrogen oxidation reaction under alkaline conditions

With the increased interest in the development of hydrogen fuel cells as a plausible alternative to internal combustion engines, recent work has focused on creating alkaline fuel cells (AFC), which employ an alkaline environment. Working in alkaline as opposed to acidic media yields a number of tangible benefits, including (i) the ability to use cheaper and plentiful precious-metal-free catalysts, due to their increased stability, (ii) a reduction in the amount of degradation and corrosion of Pt-based catalysts, and (iii) a longer operational lifetime for the overall fuel cell configuration. However, in the absence of Pt, no catalyst has achieved activities similar to those of Pt. Herein, we have synthesized a number of crystalline ultrathin PtM alloy nanowires (NWs) (M = Fe, Co, Ru, Cu, Au) in order to replace a portion of the costly Pt metal without compromising on activity while simultaneously adding in metals known to exhibit favorable synergistic ligand and strain effects with respect to the host lattice. In fact, our experiments confirm theoretical insights about a clear and correlative dependence between measured activity and chemical composition. We have conclusively demonstrated that our as-synthesized alloy NW catalysts yield improved hydrogen oxidation reaction (HOR) activities as compared with amore » commercial Pt standard as well as with our as-synthesized Pt NWs. The Pt7Ru3 NW system, in particular, quantitatively achieved an exchange current density of 0.493 mA/cm2, which is higher than the corresponding data for Pt NWs alone. In addition, the HOR activities follow the same expected trend as their calculated hydrogen binding energy (HBE) values, thereby confirming the critical importance and correlation of HBE with the observed activities.« less
Authors:
;  [1] ;  [2] ;  [2] ;  [2] ;  [3] ;  [3] ;  [3] ;  [3]
  1. State Univ. of New York at Stony Brook, Stony Brook, NY (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. State Univ. of New York at Stony Brook, Stony Brook, NY (United States)
  3. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
OSTI Identifier:
1257946
Report Number(s):
BNL--112207-2016-JA
Journal ID: ISSN 2155-5435; R&D Project: PM037; KC0201030
Grant/Contract Number:
SC00112704
Type:
Accepted Manuscript
Journal Name:
ACS Catalysis
Additional Journal Information:
Journal Volume: 6; Journal Issue: 6; Journal ID: ISSN 2155-5435
Publisher:
American Chemical Society
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY hydrogen binding energy; hydrogen oxidation reaction; ligand effect; nanowires; Pt-based alloy