Carbon dioxide adsorption and activation on ionic liquid decorated Au(111) surface: A DFT study

Area of Science:

• Computational Chemistry
• Surface Science
• Catalysis

Background:

• Carbon dioxide (CO2) activation is crucial for sustainable chemical synthesis.
• Ionic liquids (ILs) offer tunable properties for catalytic applications.
• Heterogeneous catalysis on metal surfaces is vital for industrial processes.

Purpose of the Study:

• To investigate the adsorption and activation mechanisms of CO2 on ionic liquids ([CnMIm]+[Cl]−, n=0–6) anchored to a Au(111) surface.
• To explore the potential of ILs@Au(111) interfaces for CO2 conversion into value-added products.
• To establish a model for designing efficient heterogeneous catalysts for CO2 utilization.

Main Methods:

• First-principle calculations were employed to simulate CO2 adsorption and reaction pathways.
• The study focused on the liquid-solid interface model of ILs attached to a Au(111) surface.
• Analysis of CO2 adsorption modes, including π-stacking and lone pair interactions, was performed.

Main Results:

• CO2 adsorption occurs via parallel π-stacking or lone pair (lp)···π interactions, influenced by the CO2 landing angle.
• These physisorption modes effectively activate CO2 for further chemical transformations.
• The ILs@Au(111) interface demonstrated reduced activation energy for CO2 conversion to formic acid (HCOOH).

Conclusions:

• A suitable interface material, like ILs@Au(111), is sufficient to activate CO2.
• The findings provide valuable insights for designing novel heterogeneous catalysts for CO2 conversion.
• This electrode/electrolyte interface model advances the field of CO2 utilization and sustainable chemistry.