Synergistic Tuning of Oxygen Vacancies, Basic Sites, and Metal−Support Interaction in NiAlCeLa LDH-Derived Catalyst for Low-Temperature CO2 Methanation
Issued Date
2026-01-01
Resource Type
eISSN
21555435
Scopus ID
2-s2.0-105036274383
Journal Title
ACS Catalysis
Rights Holder(s)
SCOPUS
Bibliographic Citation
ACS Catalysis (2026)
Suggested Citation
Gebreegziabher H.G., Sivakumar M., Kunthakudee N., Rungtaweevoranit B., Sano N., Ratchahat S., Charinpanitkul T. Synergistic Tuning of Oxygen Vacancies, Basic Sites, and Metal−Support Interaction in NiAlCeLa LDH-Derived Catalyst for Low-Temperature CO2 Methanation. ACS Catalysis (2026). doi:10.1021/acscatal.6c00074 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/116358
Title
Synergistic Tuning of Oxygen Vacancies, Basic Sites, and Metal−Support Interaction in NiAlCeLa LDH-Derived Catalyst for Low-Temperature CO2 Methanation
Corresponding Author(s)
Other Contributor(s)
Abstract
Developing Ni-based catalysts for low-temperature CO<inf>2</inf> methanation remains challenging due to the kinetic limitation. Layered double hydroxides (LDHs) have emerged as versatile catalyst precursors enabling structural tunability through cation incorporation. Here, we report a stepwise catalyst design strategy implemented at the LDH stage, in which Ce and La are simultaneously incorporated into NiAl-LDH to engineer structural defects and catalytic functionality. A series of NiAl-LDH, NiAlCe-LDH, and NiAlCeLa-LDH materials was synthesized via a one-pot hydrothermal method with designated metal ratios (Ni/Al= 1−5, Ce/Al = 0.2−1.0, and La/Ce = 0.025−1.0). Systematic characterization reveals that oxygen vacancies (O<inf>V</inf>), weak and medium basic sites (WBS/MBS), and metal−support interaction (MSI) govern the catalytic activity of the catalysts. Incorporation of Ce into Ni<inf>2</inf>Al-LDH generates abundant O<inf>V</inf>, while subsequent La introduction into Ni<inf>2</inf>AlCe<inf>0.4</inf>La<inf>0.05</inf>-LDH provides additional structural and electronic benefits. Upon calcination, insertion of La into the ceria lattice of Ni<inf>2</inf>AlCe<inf>0.4</inf>La<inf>0.05</inf> further amplifies O<inf>V</inf> formation, enriches WBS/MBS, and enhances NiO reducibility and interfacial Ni electron density. Owing to these synergistic effects, Ni<inf>2</inf>AlCe<inf>0.4</inf>La<inf>0.05</inf> provides 85% CO<inf>2</inf> conversion, a CH<inf>4</inf> production rate of 69.5 mmol g<sup>−1</sup> h<sup>−1</sup>, and a TOF of 0.35 s<sup>−1</sup> at 180 °C. In situ DRIFTS analysis reveals that OH groups and O<inf>V</inf> in Ni<inf>2</inf>AlCe<inf>0.4</inf>La<inf>0.05</inf> facilitate CO<inf>2</inf> activation into HCO<inf>3</inf> and b-CO<inf>3</inf> species, which are easily hydrogenated to CH<inf>4</inf> via the formate pathway. This work establishes a rational catalyst design strategy to integrate O<inf>V</inf> formation, surface basicity modulation, and MSI tuning for low-temperature CO<inf>2</inf> methanation.