Noncovalent Functionalization of Black Phosphorus: Free Energy Simulations vs Adsorption Experiments

We investigate the adsorption behavior of various molecules on black phosphorus (BP), employing moleculardynamics (MD)-based free energy calculations in combination with experimental measurements. We find a semiquantitativeagreement between experiment and theory. Our approach works best at the low concentration limit, as this allows us to neglectadsorbate−adsorbate interactions, both in solution and on the surface. We also conducted simulations at high concentrations toqualitatively estimate these effects and propose a suitable isotherm model for adsorbates. Our results highlight the impact ofmolecular structure, shape, polarity, and the alignment of adsorbates relative to the BP surface along with the solvent environmenton adsorption. Our approach uses generally available methods and can be extended to arbitrary organic molecules and solvents,potentially allowing for a high throughput screening of candidate molecules for noncovalent functionalization of BP.