skip to main content

DOE PAGESDOE PAGES

Title: Surface oxygen exchange properties of Sr doped La2NiO4+δ as SOFC cathode: Thin-film electrical conductivity relaxation investigation

La2-xSrxNiO4+δ dense films are prepared by a novel spray-modified pressing method. The surface reaction kinetics is investigated via electrical conductivity relaxation (ECR). The layer thickness, 5~10 μm, is much less than the characteristic length of lanthanum nickelates, resulting in surface-controlled situation and allowing more accurate fitting than the traditional pellets ECR on the surface exchange coefficient (k). k for LNO is 1.6×10-5 cm/s in 0.2 atm at 700°C. Sr doping impairs the exchange kinetics, and k of Sr40 is about one order of magnitude smaller than undoped one. Interstitial oxygen and Ni oxidation state are suggested the predominant roles in determining surface kinetics. In conclusion, given the properties of the thin-film herein developed by spray-modified pressing is closer to those in practical porous electrode compared to pulsed laser deposited film in terms of preferential orientation and strain, it warrants the use of such a method in a variety of pertinent investigations.
Authors:
 [1] ;  [1] ;  [1] ;  [1]
  1. West Virginia Univ., Morgantown, WV (United States)
Publication Date:
OSTI Identifier:
1267276
Grant/Contract Number:
FE0009675
Type:
Accepted Manuscript
Journal Name:
ECS Transactions (Online)
Additional Journal Information:
Journal Name: ECS Transactions (Online); Journal Volume: 68; Journal Issue: 1; Journal ID: ISSN 1938-6737
Publisher:
Electrochemical Society
Research Org:
West Virginia Univ., Morgantown, WV (United States)
Sponsoring Org:
USDOE
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION La2-xSrxNiO4+δ; dense films