The investigation of optoelectronic, magnetic and dynamical properties of Ce and Ti doped 2D blue phosphorene: A dispersion corrected DFT study

Abstract

The present study has been performed to investigate optoelectronic, magnetic and dynamical properties of pristine blue phosphorene (BP), (Ce, Ce–Ce, Ti, Ti–Ti) doped BP and single vacancy BP using the Cambridge Serial Total Energy Package (CASTEP) simulation code based on the density functional theory (DFT). The optical and vibrational properties were carried out by employing dispersion corrected density functional theory. The calculated lattice constants for pristine blue phosphorene a = b = 3.33 Å are found to be improved by Tkatchenko-Scheffler (TS) and Grimme (G06) schemes for 2D phosphorene. The band structures and density of states results have figured out indirect band gaps as 1.93eV (pristine), 0.35eV (with single vacancy), 0.37eV (Ce doped), 0.68eV (Ti doped), and 0.56eV (Ti–Ti doped) in blue phosphorene. Whereas, no band gap has been observed for Ce–Ce doped blue phosphorene. The phonon dispersion curves obtained by density functional theory perturbation theory presented dynamical stability of the studied materials without any imaginary modes of phonon spectra. The Raman active optical modes of vibrations are found at the highest frequency of 520 cm−1. The Spin polarized density of states portray that (Ce, Ti, Ti–Ti) doped blue phosphorene exhibit semi-metallic like behavior due to hybridization of 4f, 5d and 3d localized energy states. The optical properties show that the plasma frequencies occurred at 11.34eV (pristine), 8.6 eV (Ce-doped) and 9.03eV (Ti-doped) blue phosphorene. Moreover, significant shift of absorption peak towards high energy range is clear signature of the blue shift.