  First principle modeling of nitrogen- and boron-doped phosphorene
demonstrates the tendency toward formation of highly ordered structures.
Nitrogen doping leads to the formation of -N-P-P-P-N- lines. Further
transformation to -P-N-P-N- lines across the chains of phosphorene occurs with
increasing band gap and increasing nitrogen concentration, which coincides with
the decreasing chemical activity of N-doped phosphorene. In contrast to the
case of nitrogen, boron atoms prefer to form -B-B- pairs with the further
formation of -P-P-B-B-P-P- patterns along the phosphorene chains. The low
concentration of boron dopants converts the phosphorene from a semiconductor
into a semimetal with the simultaneous enhancement of its chemical activity.
Co-doping of phosphorene by both boron and nitrogen starts from the formation
of -B-N- pairs, which provide flat bands and the further transformation of
these pairs to hexagonal BN lines and ribbons across the phosphorene chains.

Mesoscale and Nanoscale Physics;Materials Science;Chemical Physics;Computational Physics