Electronic and transport properties of zigzag phosphorene nanoribbons with nonmetallic atom terminations

Abstract

Using the first-principles method based on density-functional theory and nonequilibrium Green's function, electronic properties of zigzag phosphorene nanoribbons (ZPNRs) terminated with nonmetallic (NM) atoms such as H, C, F, N, O, S and Si, as well as a pristine case, are studied systematically. Three possible cases are considered, namely, ZPNRs with symmetrical edge terminations, asymmetrical edge terminations, and the half-bare edge case. It is shown that the pristine ZPNRs show metallic behavior. For ZPNRs terminated with C, O, S and Si atoms, they are always metals regardless of the termination cases. For ZPNR terminated with H, F, and N, the electronic structure is either a metal or a semiconductor, which depends on the termination cases. The results from the calculated edge formation energy show that the ribbons with C, F, N, O, S and Si atom edge modifications are more stable than the H-terminated ZPNR. Moreover, an applied external transverse electric field can effectively modulate the bandgaps of ZPNRs terminated with H, F and N, especially reducing the gap with the increase of the applied external transverse electric field strength.The ZPNRs terminated with N undergo a semiconductor-to-metal transition. We also investigate the electronic transport properties in nano devices consisting of the ZPNRs terminated respectively by O and S at both edges and with the fully bare edge. It is found that O and S terminated ZPNR devices have a good linear response on bias, and the current is bigger than the pristine case. The results indicate that the introduction of NM atoms at the edge(s) can effectively modulate the electronic and transport properties of ZPNRs. These novel electronic properties suggest that PNRs are a promising candidate for future nanoelectronic and optoelectronic applications.

Two-Dimensional Black Phosphorus Nanomaterials: Emerging Advances in Electrochemical Energy Storage Science

“…Therefore, a wide solar absorption become possible, and it allows BP to be applied in photovoltaic devices such as solar cell [28]. In addition to the layer thickness effect, its bandgap can be tuned by functional groups, strain [63,64], rotation angles [65] between phosphorene sheets and electrical field. Sun et al [64] theoretically investigated the electronic band properties of phosphorene nanoribbons by doping non-metallic elements (e.g., C, F, N, S, −3 Single layer density [47] O, and Si) on the edge terminated with zigzag configuration.…”

“…In addition to the layer thickness effect, its bandgap can be tuned by functional groups, strain [63,64], rotation angles [65] between phosphorene sheets and electrical field. Sun et al [64] theoretically investigated the electronic band properties of phosphorene nanoribbons by doping non-metallic elements (e.g., C, F, N, S, −3 Single layer density [47] O, and Si) on the edge terminated with zigzag configuration. Phosphorene nanoribbons always show metallic behavior by doping with C, O, S, and Si, while it could behave like metal or semiconductor when zigzag edge is doped with H, F, or N. Moreover, enhancing externally applied transverse electric field could reduce the bandgap of phosphorene nanoribbons doped with H, F, and N effectively.…”

“…Computed bandgap structure for zigzag and armchair nanoribbons is shown on the top and bottom, respectively. Reproduced with permission [ 64 ]. Copyright 2020 Royal Society of Chemistry …”

“…When nanoholes are introduced to phosphorene nanoribbons, zigzag edge nanoribbons go through a direct-to-indirect bandgap transition, while armchair edge ones still possess their direct bandgap feature with increasing bandgap (Fig. 1 g) [ 64 ]. Introducing nanoholes has little effect on structural stability, but the bandgap can thus be manipulated by applying transverse electric field or mechanical strain.…”

Electric-Field Control in Phosphorene-Based Heterostructures

“…Applying a lateral electric field, the band gaps of passivated zPNRs and aPNRs can be reduced and eventually closed [ 23 ]. This can be further influenced by edge modifications employing non-metallic atoms [ 24 ]. Edge functionalization by transition-metal (TM) atoms produces spin polarization, and rectification for a spin component can be achieved [ 25 ].…”