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Title: Chemical Stability of BaMg 0.33 Nb 0.67-X Fe x O 3-δ in High Temperature Methane Conversion Environments
Doped perovskite metal oxide catalysts of the form A(BxM1-x)O3-δhave been instrumental in the development of solid oxide electrolyzers/fuel cells. In addition, this material class has also been demonstrated to be effective as a heterogeneous catalyst. Co-doped barium niobate perovskites have shown remarkable stability in highly acidic CO2sensing measurements/environments (1). However, the reason for their chemical stability is not well understood. Doping with transition metal cations for B site cations often leads to exsolution under reducing conditions. Many perovskites used for the oxidative coupling of methane (OCM) or the electrochemical oxidative coupling of methane (E-OCM) either lack long term stability, or catalytic activity within these highly reducing methane environments. The Mg and Fe co-doped barium niobate BaMg0.33Nb0.67-xFexO3-δshown activity in E-OCM reactors over long periods (2) (>100 hrs) with no iron metal exsolution observed by diffraction or STEM EDX measurements. In contrast, iron decorated BaMg0.33Nb0.67O3showed little C2 conversion activity.  more » « less
Award ID(s):
1828731 1647722
PAR ID:
10487371
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
IOP Science
Date Published:
Journal Name:
ECS Transactions
Volume:
111
Issue:
6
ISSN:
1938-5862
Page Range / eLocation ID:
587 to 593
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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