Exploring surface reactivity of phosphorous-doped (6,0) and (4,4) BC3 nanotubes: a DFT study

We report a density functional theory study on the electronic structure properties of pristine and phosphorous-doped (6,0) and (4,4) single-walled BC3 nanotubes (BC3NTs). We examine the usefulness of local reactivity descriptors to predict the reactivities of different carbon/boron atomic sites on the external surface of the tubes. Electrostatic potentials VS(r) and average local ionization energies ĪS(r) are computed on the surface of the investigated BC3NTs. A general feature of the systems considered here is that the magnitudes of negative VS(r) associated with carbon atoms tend to be stronger when the boron atom is substituted with a phosphorous atom. In order to verify the surface reactivity pattern based on the chosen reactivity descriptors, we calculated the reaction energies for the interaction of an H+ ion or H radical with external surface of the (6,0) and (4,4) BC3NTs. It is clear that, for each nanotube studied, the reaction energies correlate well with the values of VS(r) and ĪS(r).