Boosting Low-Temperature CO₂ Hydrogenation over Ni-based Catalysts by Tuning Strong Metal-Support Interactions

Area of Science:

• Materials Science
• Catalysis
• Environmental Chemistry

Background:

• Developing cost-effective and efficient transition-metal catalysts for low-temperature carbon dioxide (CO2) activation is crucial but challenging.
• Commercial nickel catalysts typically require high temperatures (>350°C) for effective CO2 methanation.
• Optimizing catalyst active sites is key to enhancing CO2 conversion efficiency.

Purpose of the Study:

• To design a low-cost, efficient transition-metal catalyst for low-temperature CO2 methanation.
• To investigate a strategy for boosting CO2 methanation by regulating the local electron density of active sites.
• To achieve high CO2 conversion and methane selectivity at reduced operating temperatures.

Main Methods:

• Development of a novel Ni/ZrO2 catalyst by regulating local electron density.
• Utilized in situ spectroscopic characterization techniques to study catalyst behavior.
• Tested catalyst performance for CO2 methanation at 230°C with a GHSV of 12,000 mL g⁻¹ h⁻¹.

Main Results:

• The optimal Ni/ZrO2 catalyst demonstrated excellent low-temperature performance: 84.0% CO2 conversion and 98.6% CH4 selectivity at 230°C.
• The catalyst maintained high performance for 106 hours, indicating robust stability.
• In situ studies revealed that abundant oxygen vacancies in monoclinic ZrO2 enhanced Ni electron density via strong metal-support interactions, facilitating CO2 activation.

Conclusions:

• The developed Ni/ZrO2 catalyst represents one of the best-performing Ni-based catalysts for CO2 methanation to date.
• Regulating local electron density through strong metal-support interactions and oxygen vacancies is an effective strategy for enhancing catalyst performance.
• Findings offer valuable insights for designing advanced catalysts for CO2 emission abatement and other applications.