Synergistic Assembly of Charged Oligomers and Amino Acids at the Air-Water Interface: An Avenue toward Surface-Directed CO₂ Capture

Interfaces are considered a major bottleneck in the capture of CO₂ from air. Efforts to design surfaces to enhance CO₂ capture probabilities are challenging due to the remarkably poor understanding of chemistry and self-assembly taking place at these interfaces. Here, we leverage surface-specific vibrational spectroscopy, Langmuir trough techniques, and simulations to mechanistically elucidate how cationic oligomers can drive surface localization of amino acids (AAs) that serve as CO₂ capture agents speeding up the apparent rate of absorption. We demonstrate how tuning these interfaces provides a means to facilitate CO₂ capture chemistry to occur at the interface, while lowering surface tension and improving transport/reaction probabilities. We show that in the presence of interfacial AA-rich aggregates, one can improve capture probabilities vs that of a bare interface, which holds promise in addressing climate change through the removal of CO₂ via tailored interfaces and associated chemistries.