The Dry Reforming of Methane (DRM) is an intriguing process to convert two greenhouse gases, CH4 and CO2, into syngas (CO+H2) and to upgrade biogas into biosyngas. However, the challenges of high operating temperatures and catalyst deactivation have hindered its large-scale implementation so far. Recently, photothermal catalysis has emerged as a sustainable alternative to conventional thermocatalysis, enabling a reduction of the required temperature and improvement of catalyst stability. This approach necessitates the development of a suitable photocatalyst. Herein, we proposed the use of active Ni nanoparticles (NPs) with plasmonic features, supported over semiconductive perovskites LaFeO3 or LaMnO3 with La-deficiency. The incorporation of Ni was achieved through either B-site substitution within the perovskite lattice or surface loading via Ammonia Deposition Precipitation (ADP), followed by a reductive treatment under H2 to yield Ni0 NPs. The prepared samples were extensively characterized by XRD, N2 physisorption, H2-TPR, SEM-EDX, HAADF STEM-EDX, XPS, UV-Vis DRS. The pre-reduced catalysts were then tested for thermal and photothermal DRM under visible light illumination (3 suns) at 600 ◦C. The Fe-based samples were poorly active because of Ni0 reoxidation, whereas a good activity and stability were ensured by Mn-perovskites, preserving the Ni0 active species. Among the Ni loading procedures, only ADP ensured improved activity in photothermal conditions thanks to high Ni NPs concentration, while the B-site doped catalyst showed better thermal than photo-activity because of low surface Ni concentration. Interestingly, light illumination was found to reduce perovskite decomposition and coke deposition. A Ni/Al2O3 reference catalyst demonstrated slightly higher activity than Ni/LaMnO3 but suffered from much faster deactivation due to coking and reoxidation.
Photothermal activation of methane dry reforming on perovskite-supported Ni-catalysts: Impact of support composition and Ni loading method
Andrea Osti
;Simone Costa;Lorenzo Rizzato;Beatrice Senoner;Antonella Glisenti
2025
Abstract
The Dry Reforming of Methane (DRM) is an intriguing process to convert two greenhouse gases, CH4 and CO2, into syngas (CO+H2) and to upgrade biogas into biosyngas. However, the challenges of high operating temperatures and catalyst deactivation have hindered its large-scale implementation so far. Recently, photothermal catalysis has emerged as a sustainable alternative to conventional thermocatalysis, enabling a reduction of the required temperature and improvement of catalyst stability. This approach necessitates the development of a suitable photocatalyst. Herein, we proposed the use of active Ni nanoparticles (NPs) with plasmonic features, supported over semiconductive perovskites LaFeO3 or LaMnO3 with La-deficiency. The incorporation of Ni was achieved through either B-site substitution within the perovskite lattice or surface loading via Ammonia Deposition Precipitation (ADP), followed by a reductive treatment under H2 to yield Ni0 NPs. The prepared samples were extensively characterized by XRD, N2 physisorption, H2-TPR, SEM-EDX, HAADF STEM-EDX, XPS, UV-Vis DRS. The pre-reduced catalysts were then tested for thermal and photothermal DRM under visible light illumination (3 suns) at 600 ◦C. The Fe-based samples were poorly active because of Ni0 reoxidation, whereas a good activity and stability were ensured by Mn-perovskites, preserving the Ni0 active species. Among the Ni loading procedures, only ADP ensured improved activity in photothermal conditions thanks to high Ni NPs concentration, while the B-site doped catalyst showed better thermal than photo-activity because of low surface Ni concentration. Interestingly, light illumination was found to reduce perovskite decomposition and coke deposition. A Ni/Al2O3 reference catalyst demonstrated slightly higher activity than Ni/LaMnO3 but suffered from much faster deactivation due to coking and reoxidation.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.