Structural Reversibility and Nickel Particle stability in Lanthanum Iron Nickel Perovskite-Type Catalysts.
Perovskite-type oxides have shown the ability to reversibly segregate precious metals from their structure. This reversible segregation behavior was explored for a commonly used catalyst metal, Ni, to prevent Ni sintering, which is observed on most catalyst support materials. Temperature-programmed reduction, X-ray diffraction, X-ray absorption spectroscopy, electron microscopy, and catalytic activity tests were used to follow the extent of reversible Ni segregation. LaFe1-xNixO3±δ(0≤x≤0.2) was synthesized using a citrate-based solution process. After reduction at 600 °C, metallic Ni particles were displayed on the perovskite surfaces, which were active towards the hydrogenation of CO2. The overall Ni reducibility was proportional to the Ni content and increased from 35 % for x=0.05 to 50 % for x=0.2. Furthermore, Ni could be reincorporated reversibly into the perovskite lattice during reoxidation at 650 °C. This could be exploited for catalyst regeneration under conditions under which impregnated materials such as Ni/LaFeO3±δand Ni/Al2O3suffer from sintering.
Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.|Institute of Chemical Sciences and Engineering, École polytechnique fédérale de Lausanne (EFPL), 1015, Lausanne, Switzerland.
Patrick
P
Steiger
IMPE-Institute for Materials and Process Engineering, Zurich University of Applied Sciences, 8400, Winterthur, Switzerland.
Renaud
0000-0003-1455-4656
R
Delmelle
Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.|Institute of Environmental Engineering, École polytechnique fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
Debora
D
Foppiano
ICP-Institute of Computational Physics, Zurich University of Applied Sciences, 8400, Winterthur, Switzerland.
Lorenz
0000-0002-3532-5994
L
Holzer
IMPE-Institute for Materials and Process Engineering, Zurich University of Applied Sciences, 8400, Winterthur, Switzerland.
Andre
A
Heel
Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.
Maarten
0000-0003-1895-9626
M
Nachtegaal
Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.|Institute of Chemical Sciences and Engineering, École polytechnique fédérale de Lausanne (EFPL), 1015, Lausanne, Switzerland.
Oliver
0000-0002-7268-7257
O
Kröcher
Paul Scherrer Institut, 5232, Villigen PSI, Switzerland.
Davide
0000-0002-9354-5231
D
Ferri
D017610:Calcium Compounds; D002384:Catalysis; D006865:Hydrogenation; D007501:Iron / Q000737:chemistry*; D007811:Lanthanum / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry; D014025:Titanium
D017610:Calcium Compounds; D010087:Oxides; C059910:perovskite; D007811:Lanthanum; D009532:Nickel; D014025:Titanium; D007501:Iron
co2 hydrogenation; particles; perovskite phase; structural reversibility; supported catalysts