Synthesis and Characterization of Fluorite-Type La2Ce2O7 Plasma Sprayable Powder for TBCs Application
Open Access
Abstract
This work focuses on the fabrication of lanthanum cerate (La2Ce2O7, LC) powders via two chemical routes: modified Pechini sol-gel method and solid-state synthesis. The synthesized LC powders were heat treated in the temperature range of 1000–1400 °C for 6 h and investigated as a material for thermal barrier coating (TBC) applications. For this purpose, the powder morphology, chemical composition, crystal structure and thermal stability were studied. Scanning electron microscopy (SEM) of the synthesized powders revealed an agglomerated structure consisting of fine and uniformly distributed grains. Energy-dispersive X-ray spectroscopy (EDXS) indicated that the chemical compositions of the LC powders were similar to the stoichiometric ratio of La2Ce2O7. A cubic fluorite structure was observed by X-ray diffraction analysis (XRD) after calcining the LC powder prepared by solid-state synthesis at 1300 °C. In contrast, there was always a fluorite structure in the LC powder synthesized by the Pechini sol-gel method after heat treatment over the entire temperature range. The thermal behavior of the LC powders was analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TG) in the temperature range of 25–1300 °C. Neither an obvious mass change nor a visible energy change was observed within the tested temperature range, indicating high phase stability of the LC powder and its suitability for TBC applications. Spheroidization on the prepared LC powders was also investigated, revealing that powder size and morphology had a significant impact on the spheroidization efficiency.Keywords
Funding Information
- Centre for Functional and Surface Functionalised Glass (CEGLASS) (313011R453, 739566, 1/0171/21)
- European Regional Development Fund (313011R453, 739566, 1/0171/21)
- European Union’s Horizon 2020 (313011R453, 739566, 1/0171/21)
- VEGA (313011R453, 739566, 1/0171/21)
This publication has 37 references indexed in Scilit:
- Autothermal steam reforming of ethanol over La2Ce2−Ru O7 (x= 0–0.35) catalyst for hydrogen productionApplied Catalysis B: Environment and Energy, 2013
- Doped nanosized ceria solid solutions for low temperature soot oxidation: Zirconium versus lanthanum promotersApplied Catalysis B: Environment and Energy, 2010
- Preparation of La2Ce2O7 Nano-Powders by Molten Salts MethodAdvanced Materials Research, 2009
- Precipitation of Nanocrystalline CeO2 Using TriethanolamineLangmuir, 2008
- On improving the phase stability and thermal expansion coefficients of lanthanum cerium oxide solid solutionsScripta Materialia, 2006
- The crystal structure of ionic conductor LaxCe1–xO2–x/2Journal of the European Ceramic Society, 2004
- Lanthanum–Cerium Oxide as a Thermal Barrier‐Coating Material for High‐Temperature ApplicationsAdvanced Materials, 2003
- Spray-drying of ceramics for plasma-spray coatingJournal of the European Ceramic Society, 2000
- The utilization of ceria in industrial catalysisCatalysis Today, 1999
- Raman study of: Second-order scattering, lattice dynamics, and particle-size effectsPhysical Review B, 1993