Charge-modulated CO₂ capture

Recently, the concept of using charge-modulation to manipulate the interaction of adsorbate molecules such as CO₂ on certain sorbent materials has been advanced through a series of first principle computational predictions. The interactions switched on through charge-modulation shifting the Fermi level are in part, but by no means exclusively, electrostatic. In addition to electrostatics, the Fermi level shifting can be viewed as a way to modulate not only the position but also the identity and character of the frontier orbitals on the sorbent materials that engage with the adsorbate molecules. Thus, a rich new space for electrochemical modulation of surface-molecular interactions—guided by first principle computational modeling—suggests itself. Here we summarize the growing computational literature on switchable CO₂ capture strategies. We also provide some new insights into contrasting electrostatic versus chemical responses to charge-modulation as exemplified by water versus CO₂ on N-doped graphene surfaces, which suggest that this CO₂ capture strategy could be water tolerant.