Computational Design of Oligopeptides as Carbon Capture Agents

This work presents a computational framework for understanding and designing bioinspired materials for CO₂ capture. We started by calculating highly accurate reference interaction energies with electronic structure theory for amino acid-CO₂ complexes and benchmarking different density functionals for performing large-scale DFT calculations on oligopeptide-CO₂ molecular systems. Building on this, we explored all possible dipeptides, revealing that cooperative effects significantly enhance CO₂ binding, particularly in sequences containing polar residues. We then developed TriScore, a descriptor-based ranking metric, to screen 8000 tripeptides for CO₂ interaction. DFT and SAPT0 analyses confirmed that the top-ranking tripeptides exhibit stronger, electrostatically driven non-covalent interactions. Finally, we extended our investigation to amino acids in solution to evaluate their potential in solvent-based direct air capture systems. This progression from single amino acids to solution-phase systems offers a scalable strategy for designing oligopeptide-based CO₂ sorbents.