Exsolution of Fe-Ni alloy nanoparticles from (La,Sr)(Cr,Fe,Ni)O3 perovskites as potential oxygen transport membrane catalysts for methane reforming
Abstract
(La0.75Sr0.25)(Cr0.5Fe0.5−xNix)O3 perovskites were investigated as potential catalysts for oxygen transport membranes for methane reforming applications. XRD was performed to study the structural changes that took place when Fe was partially substituted by Ni, in both oxidising and reducing environments. TGA measurements demonstrated that the oxygen deficiency of these perovskites under reducing conditions was enhanced by increasing the level of Ni doping, due to the reduction of the Fe3+/Fe4+ and Ni2+ species to lower cation valences. SEM and TEM-EDX analyses showed that upon reduction exsolution of bimetallic Fe–Ni alloy nanoparticles took place on the surface of the perovskite, which was beneficial for the catalyst's activity. The optimum stoichiometry was the (La0.75Sr0.25)(Cr0.5Fe0.35Ni0.15)O3 perovskite, which during catalytic testing, demonstrated 72% CH4 conversion, which was 20 times higher than that of the initial perovskite.
Citation
Papargyriou , D , Miller , D N & Irvine , J T S 2019 , ' Exsolution of Fe-Ni alloy nanoparticles from (La,Sr)(Cr,Fe,Ni)O 3 perovskites as potential oxygen transport membrane catalysts for methane reforming ' , Journal of Materials Chemistry A , vol. 7 , no. 26 , pp. 15812-15822 . https://doi.org/10.1039/c9ta03711j
Publication
Journal of Materials Chemistry A
Status
Peer reviewed
ISSN
2050-7488Type
Journal article
Description
Authors acknowledge support from the EPSRC for Platform Grant EP/K015540/1 and EPSRC Capital for Great Technologies Grant EP/L017008/1.Collections
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