TY - JOUR
T1 - Strain Effects on Oxygen Reduction Activity of Pr2NiO4 Caused by Gold Bulk Dispersion for Low Temperature Solid Oxide Fuel Cells
AU - Kim, Sun Jae
AU - Akbay, Taner
AU - Matsuda, Junko
AU - Takagaki, Atsushi
AU - Ishihara, Tatsumi
N1 - Funding Information:
This study was financially supported by a Grant-in-Aid for Specially Promoted Research (No. 16H06293) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan through the Japan Society for the Promotion of Science (JSPS). We also acknowledged the useful discussion of Dr. Hajime Kusaba in Kyushu University of XPS measurement.
Publisher Copyright:
© Copyright 2019 American Chemical Society.
PY - 2019/2/25
Y1 - 2019/2/25
N2 - Effects of tensile strain induced by the dispersion of Au nanoparticles in Pr2NiO4-based oxide on the oxygen reduction reaction were investigated. Au-dispersed Pr1.9Ni0.71Cu0.41Ga0.05O4+ (PNCG) showed a much decreased cathodic overpotential, and a cell using Au-dispersed PNCG showed a significantly higher power density, approximately 2.5 times higher than that of a cell using PNCG without dispersed Au. The smallest overpotential was achieved at 3-5 mol % dispersion of Au nanoparticles, at which the largest tensile strain was observed. Impedance measurements suggested that the impedance arc in the lower frequency range was mainly decreased; therefore, the increased activity to oxygen reduction was attributed to the increased bulk and surface diffusivity of oxide ions. Electron energy loss spectroscopy (EELS) shows that oxygen in the strained region was in a more reduced state and this oxygen could be assigned to interstitial oxygen which is highly mobile. In addition, density functional theory (DFT) analysis suggested that bond destabilization was attributed to the increase in energy of occupied ∗ orbitals of surface peroxo species on tensile strained surfaces. Therefore, increased cathodic performance of PNCG by Au nanoparticle dispersion could be assigned to the increased diffusivity by tensile strain.
AB - Effects of tensile strain induced by the dispersion of Au nanoparticles in Pr2NiO4-based oxide on the oxygen reduction reaction were investigated. Au-dispersed Pr1.9Ni0.71Cu0.41Ga0.05O4+ (PNCG) showed a much decreased cathodic overpotential, and a cell using Au-dispersed PNCG showed a significantly higher power density, approximately 2.5 times higher than that of a cell using PNCG without dispersed Au. The smallest overpotential was achieved at 3-5 mol % dispersion of Au nanoparticles, at which the largest tensile strain was observed. Impedance measurements suggested that the impedance arc in the lower frequency range was mainly decreased; therefore, the increased activity to oxygen reduction was attributed to the increased bulk and surface diffusivity of oxide ions. Electron energy loss spectroscopy (EELS) shows that oxygen in the strained region was in a more reduced state and this oxygen could be assigned to interstitial oxygen which is highly mobile. In addition, density functional theory (DFT) analysis suggested that bond destabilization was attributed to the increase in energy of occupied ∗ orbitals of surface peroxo species on tensile strained surfaces. Therefore, increased cathodic performance of PNCG by Au nanoparticle dispersion could be assigned to the increased diffusivity by tensile strain.
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U2 - 10.1021/acsaem.8b01776
DO - 10.1021/acsaem.8b01776
M3 - Article
AN - SCOPUS:85064973763
SN - 2574-0962
VL - 2
SP - 1210
EP - 1220
JO - ACS Applied Energy Materials
JF - ACS Applied Energy Materials
IS - 2
ER -