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  • Operando characterization of metallic and bimetallic electrocatalysts for SOFC fuel electrodes operating under internal methane reforming conditions
Title: Operando characterization of metallic and bimetallic electrocatalysts for SOFC fuel electrodes operating under internal methane reforming conditions
Linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and operando Raman spectroscopy were used to study the electrochemical performance and carbon tolerance of SOFCs operating with niobium doped SrTiO 3 (STN) anodes infiltrated with combinations of Ni, Co, and Ce 0.8 Gd 0.2 O 2 (CGO) added to improve catalytic activity. Cell anodes were exposed to fuel feeds of humidified H 2 , pure CH 4 and combinations of CO 2 and CH 4 at an operating temperature of 750 °C. Under pure CH 4 , Raman data show that carbon forms on all anodes containing Ni. In cells with CGO, deposited carbon results in a decreased polarization resistance. This behavior may be due to benefits conferred by CGO to the electrocatalytic activity of triple phase boundaries, presumably through improved oxide ion conductivity and/or due to carbon securing a better electrical connection in the electrodes. Raman spectra from Co-only containing anodes show no sign of carbon deposition. The absence of observable carbon together with low frequency processes observed in the EIS suggest that Co may play a role in oxidizing carbon before measurable amounts accumulate.  more » « less
Award ID(s):
1710695
PAR ID:
10393669
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry A
Volume:
10
Issue:
10
ISSN:
2050-7488
Page Range / eLocation ID:
5550 to 5560
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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