Unveiling protic amino acid ionic liquids for the efficient capture of carbon dioxide

Abstract

A series of novel protic amino acid ionic liquids (PAAILs) are designed and synthesized for the first time through acid–base neutralization and an ion exchange reaction. Among the synthesised PAAILs, the [DBNH][Maba] PAAIL has the largest CO₂ absorption capacity of 0.78 mol mol⁻¹ (0.142 g g⁻¹) at 313.2 K. The PAAILs are found to be efficient, reversible, and selective CO₂ absorbents.