Publication d'Alexander Stangl & Adeel Riaz
L'article intitulé "Tailored nano-columnar La2NiO4 cathodes for improved electrode performance" a été publié dans Journal of Materials Chemistry A.
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Ici vous trouverez l'article d'Alexander Stangl et Adeel Riaz:
"La2NiO4 is a very promising cathode material for intermediate and low temperature solid oxide cell applications, due to its good electronic and ionic conductivity, together with its high oxygen exchange activity with a low activation energy. Oxygen incorporation and transport in La2NiO4 (L2NO4) thin films is limited by surface reactions. Hence, tailoring the morphology is expected to lead to an overall improvement of the electrode performance. We report on the growth of nano-architectured La2NiO4 thin film electrodes by Pulsed Injection Metal Organic Vapour Deposition (PI-MOCVD), achieving vertically gapped columns with multi-fold active surface area, leading to much faster oxygen exchange. This nano-columnar structure is rooted in a dense bottom layer serving as good electronic and ionic conduction pathway. The microstructure is tuned by modification of the growth temperature and characterised by SEM, TEM and XRD. We studied the effect of surface activity by electrical conductivity relaxation measurements in fully dense and nano-columnar La2NiO4 thin films of various thicknesses grown on several different single crystal substrates. Our results demonstrate that the increased surface area, in combination with the opening of different surface terminations, leads to a significant enhancment of the total exchange activity in our films with optimized nano-architectured microstructure."
"La2NiO4 is a very promising cathode material for intermediate and low temperature solid oxide cell applications, due to its good electronic and ionic conductivity, together with its high oxygen exchange activity with a low activation energy. Oxygen incorporation and transport in La2NiO4 (L2NO4) thin films is limited by surface reactions. Hence, tailoring the morphology is expected to lead to an overall improvement of the electrode performance. We report on the growth of nano-architectured La2NiO4 thin film electrodes by Pulsed Injection Metal Organic Vapour Deposition (PI-MOCVD), achieving vertically gapped columns with multi-fold active surface area, leading to much faster oxygen exchange. This nano-columnar structure is rooted in a dense bottom layer serving as good electronic and ionic conduction pathway. The microstructure is tuned by modification of the growth temperature and characterised by SEM, TEM and XRD. We studied the effect of surface activity by electrical conductivity relaxation measurements in fully dense and nano-columnar La2NiO4 thin films of various thicknesses grown on several different single crystal substrates. Our results demonstrate that the increased surface area, in combination with the opening of different surface terminations, leads to a significant enhancment of the total exchange activity in our films with optimized nano-architectured microstructure."