Ni-based hydrotalcite-derived catalysts for enhanced CO2 methanation: Thermal tuning of the metal-support interaction

• Published in: Applied catalysis. B, Environmental Environmental, 2024-01, Vol.340, p.123245, Article 123245
• Main Authors: Ren, Jie, Lei, Han, Mebrahtu, Chalachew, Zeng, Feng, Zheng, Xusheng, Pei, Gang, Zhang, Wenhua, Wang, Zhandong
• Format: Article
• Language: English
• Subjects: CO2 methanation; DFT calculation; Metal-support interaction; Ni-based hydrotalcite-derived catalyst; Thermal treatment
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2023.123245

Metal-support interaction (MSI) is recognized as an important factor affecting catalyst activity in CO2 methanation, but a feasible strategy to adjust MSI during catalyst preparation is not yet very clear. Herein, we designed a series of Mg-Al hydrotalcites calcined at different temperatures as supports for Ni-based catalysts preparation and investigated the relationship between MSI and catalytic activity. Through various characterizations, it is confirmed that the MSI can be tailored by thermal treatment resulting from phase transformation, and Ni/MAO1000 (which has strong MSI) showed the highest activity for CO2 conversion (1821 mmolCO2 mol−1 Ni min−1). Furthermore, in-situ DRIFTS experiments and DFT calculations proved that methoxy/carbonyls are key intermediates and Ni(111) is the determined crystal plane to produce CH4. This work provides an effective way to tailor the MSI of Ni-based catalysts for enhanced performance in CO2 methanation. This work provides a feasible strategy to adjust the metal-support interaction (MSI) during catalyst preparation. Mg-Al hydrotalcites calcined at higher temperatures with a strong MSI could disperse Ni and tune Ni crystal plane, which therefore showed the highest activity for CO2 conversion. [Display omitted] •Ni-based hydrotalcite-derived catalysts were proven to be active for methanation.•Thermal tuning of metal-support interaction in designed catalysts was achieved.•High CO2 conversion and CH4 selectivity was obtained over Ni/MAO1000 at 400 °C.•Key phase and methanation route were identified by in-situ DRIFTS and DFT calculation.