Ge-doped (4,4) armchair single-walled boron phosphide nanotube as a semiconductor: a computational study

Abstract

Density functional theory (DFT) calculations were performed to investigate the electronic structure properties of Ge-doped boron phosphide nanotubes (BPNTs) as a semiconductor at the B3LYP/6-31G* level of theory in order to evaluate the influence of Ge doping on (4,4) armchair BPNTs. We extended the DFT calculations to predict the electronic structure properties of Ge-doped boron phosphide nanotubes, which are very important for production of solid-state devices and other applications. The isotropic (CSI) and anisotropic (CSA) chemical shielding parameters for the sites of various 11B and 31P atoms, and the quadrupole coupling constant (C Q) and asymmetry parameter (η Q) at the sites of various 11B nuclei, were calculated in pristine and Ge-doped (4,4) armchair BPNT models. The calculations indicated that, in these two forms of Ge-doped BPNTs, the binding energies are not attractive and do not characterize a chemisorption process. In comparison with the pristine model, the band gap of the two forms of Ge-doped BPNTs is reduced and increases their electrical conductance. The dipole moments of the Ge-doped BPNT structures show notable changes with respect to the pristine model. The nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) results show that the GeB model is a more reactive material than the pristine or GeP model.