Ab initio simulations of black and blue phosphorene functionalised with chemical groups for biomolecule anchoring

Black and blue phosphorene (2D-dimensional allotropes of phosphorus) have shown fascinating electronic, optical, and magnetic properties, with promising technological applications. In this work, we studied the adsorption of amine, hydroxyl, amide, and carboxyl groups onto both black and blue phosphorenes, in order to analyse the effects of biomolecule anchoring on the structural and electronic properties of phosphenes, using density functional simulations. Analyses were carried out of six different configurations for each chemical group functionalised on black and blue phosphorene. We observed that the radicals interacted via a chemisorption regime with the nanostructures, with binding energies that varied from 1.42 to 3.78 eV. The electronic properties showed that the presence of the chemical groups altered the energy gaps for both black and blue phosphorenes, due to a presence of a half-filled level when a single radical was adsorbed. We were able to observe that functionalised two-dimensional phosphorene showed promising characteristics in terms of anchoring molecules, and particularly those of biological interest, due to its high surface area, strong coupling between phosphorene and chemical groups, and the possibility of chemically manipulating radicals.