Quantifying the efficiency of CO₂ capture by Lewis pairs

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Chemical Engineering

Background:

• Carbon dioxide (CO2) capture remains a critical challenge in environmental science.
• Frustrated Lewis pairs (FLPs) offer a promising avenue for CO2 binding.
• Efficient and rapid evaluation of FLP performance is essential for their development.

Purpose of the Study:

• To develop a time- and labor-efficient microfluidic strategy for evaluating CO2 binding efficiency.
• To compare the CO2 binding efficiency and thermodynamic parameters of various Lewis acid/base combinations.
• To investigate the CO2 capture capabilities of an archetypal FLP versus other systems.

Main Methods:

• A microfluidic platform was designed for the rapid assessment of CO2 binding.
• Evaluated CO2 uptake efficiency based on binding units in solution.
• Determined thermodynamic parameters for CO2 binding reactions.

Main Results:

• Neither tri-tert-butylphosphine (tBu3P) nor tris(pentafluorophenyl)borane (B(C6F5)3) alone effectively captured CO2.
• A combination of a specific phosphine and B(C6F5)3 was also ineffective for CO2 capture.
• An archetypal FLP (tBu3P/B(C6F5)3) exhibited higher CO2 binding efficiency than other tested FLPs and phosphines.

Conclusions:

• The microfluidic strategy provides an efficient method for evaluating CO2 binding thermodynamics.
• The archetypal FLP demonstrates significant potential for CO2 capture applications.
• This approach facilitates the rapid screening and optimization of Lewis acid/base systems for CO2 utilization.