This study investigates the structural evolution and redox characteristics of the double perovskite Sr2FeMo0.6Ni0.4O6-δ (SFMN) during hydrogen (H2) and carbon dioxide (CO2) redox cycles and explores the material performance in the Reverse Water-Gas Shift Chemical Looping (RWGS-CL) reaction. In-situ and ex-situ X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscopy (HRTEM) studies reveal that H2 reduction at temperatures above 800 °C leads to the exsolution of bimetallic Ni-Fe alloy particles and the formation of a Ruddlesden-Popper (RP) phase. A core–shell structure with Ni-Fe core and a perovskite oxide shell is formed with subsequent redox cycles, and the resulting material exhibits better performance and high stability in the RWGS-CL process. Thermogravimetric (TGA) and Temperature Programmed Reduction (TPR) and Oxidation (TPO) analyses show that the optimal reduction and oxidation temperatures for maximizing the CO yield are around 850 °C and 750 °C respectively, and that the cycled material is able to work steadily under isothermal conditions at 850 °C.
Exsolution-enhanced reverse water-gas shift chemical looping activity of Sr2FeMo0.6Ni0.4O6-δ double perovskite
Felli A.;Boaro M.
;de Leitenburg C.;Trovarelli A.;
2023-01-01
Abstract
This study investigates the structural evolution and redox characteristics of the double perovskite Sr2FeMo0.6Ni0.4O6-δ (SFMN) during hydrogen (H2) and carbon dioxide (CO2) redox cycles and explores the material performance in the Reverse Water-Gas Shift Chemical Looping (RWGS-CL) reaction. In-situ and ex-situ X-Ray Diffraction (XRD) and High-Resolution Transmission Electron Microscopy (HRTEM) studies reveal that H2 reduction at temperatures above 800 °C leads to the exsolution of bimetallic Ni-Fe alloy particles and the formation of a Ruddlesden-Popper (RP) phase. A core–shell structure with Ni-Fe core and a perovskite oxide shell is formed with subsequent redox cycles, and the resulting material exhibits better performance and high stability in the RWGS-CL process. Thermogravimetric (TGA) and Temperature Programmed Reduction (TPR) and Oxidation (TPO) analyses show that the optimal reduction and oxidation temperatures for maximizing the CO yield are around 850 °C and 750 °C respectively, and that the cycled material is able to work steadily under isothermal conditions at 850 °C.File | Dimensione | Formato | |
---|---|---|---|
1-s2.0-S1385894723048143-main.pdf
accesso aperto
Tipologia:
Versione Editoriale (PDF)
Licenza:
Creative commons
Dimensione
5.96 MB
Formato
Adobe PDF
|
5.96 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.