Published March 1, 2016 | Version v1
Journal article

X-ray photoelectron spectroscopic study of direct reforming catalysts Ln0.5Sr0.5Ti0.5Mn0.5O3±d (Ln = La, Nd, and Sm) for high temperature-operating solid oxide fuel cell

  • 1. Department of Engine Research, Korea Institute of Machinery and Materials, 156 Gajeongbuk-Ro, Daejeon 305-343 (Korea, Republic of)
  • 2. Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712 (United States)
  • 3. Faculty of Integrated Technologies, University Brunei Darussalam, Jalan Tunku Link, Gadong BE1410 (Brunei Darussalam)
  • 4. Department of Advanced Materials Science and Engineering, Hanbat National University, 125, Dongseo-Daero, Yusung-Gu, Daejeon 305-719 (Korea, Republic of)

Description

Graphical abstract: Measured Ti 2p peaks and deconvolution peaks of Nd0.5Sr0.5Ti0.5Mn0.5O3±d under oxidizing condition (left) and NSTM under reducing condition (right). - Highlights: • Chemical states of Ln0.5Sr0.5Ti0.5Mn0.5O3±d (Ln: La, Nd and Sm) were analyzed. • Charge compensation occurred with the reduction of Mn and Ti. • The Nd substitution effect allowed some Ti to convert into a metallic behavioral component. • NSTM and SSTM had a large amount of lattice oxygen; however, LSTM retained a large quantity of adsorbed oxygen. - Abstract: Chemical states of lanthanide doped perovskite for direct reforming anode catalysts, Ln0.5Sr0.5Ti0.5Mn0.5O3±d (Ln = La, Nd, and Sm) have been studied by X-ray Photoelectron Spectroscopy (XPS) in order to determine the effects of various lanthanide substitution in complex perovskites for high temperature-operating solid oxide fuel cells (HT-SOFC). The charge state of lanthanide ions remained at 3+ and the binding energies of the lanthanide ions in Ln0.5Sr0.5Ti0.5Mn0.5O3±d were located in a relatively lower range compared to those of conventional lanthanide oxides. Mn and Ti were regarded as charge compensation components in Ln0.5Sr0.5Ti0.5Mn0.5O3±d; Mn was more influential than Ti. In the cases of substituting Nd and Sm into Ln0.5Sr0.5Ti0.5Mn0.5O3±d, some portion of Ti showed metallic behavior; the specific Mn satellite peak indicating an electro-catalytic effect had occurred. Three types of oxygen species comprised of lattice oxygen, carbonate species, and adsorbed oxygen species were observed in Ln0.5Sr0.5Ti0.5Mn0.5O3±d from the O 1s spectra; a high portion of lattice oxygen was observed in both Nd0.5Sr0.5Ti0.5Mn0.5O3±d (NSTM) and Sm0.5Sr0.5Ti0.5Mn0.5O3±d (SSTM). In various respects, NSTM and SSTM will be desirable reforming catalysts and anode candidates for high temperature solid oxide fuel cell.

Availability note (English)

Available from http://dx.doi.org/10.1016/j.apsusc.2016.01.014

Additional details

Identifiers

DOI
10.1016/j.apsusc.2016.01.014;
PII
S0169-4332(16)00028-3;

Publishing Information

Journal Title
Applied Surface Science
Journal Volume
365
Journal Page Range
p. 38-46
ISSN
0169-4332
CODEN
ASUSEE

Optional Information

Copyright
Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.