Density functional theory and ab-initio molecular dynamics calculations on the opto-electronic, spintronic, and energies of pure and TiOx doped monatomic γ-graphyne

In this work, density functional theory and molecular dynamics (MD) calculations are performed on TiOx (ie, x = 1-3) doped gamma-graphyne to modify its structural, opto-electronic, and spintronic characteristics. Obtained negative binding energies (E-b) values and MD calculations suggest that TiOx substitution in gamma-graphyne is thermodynamically stable. Furthermore, the direction of charge transfer occurs from TiO1(2) clusters to the gamma-graphyne, whereas in case of TiO3, gamma-graphyne lends its charge carriers to impurity cluster. TiO2(3) cluster doping converts nonmagnetic gamma-graphyne to a magnetic material having similar to 2.00 mu(B) magnetic moment. TiO doped gamma-graphyne displays nonmagnetic narrow band indirect semiconductor behavior at M-point with similar to 1.0 eV band gap. Since TiO2(3) cluster doped gamma-graphynes carried magnetic behavior, hence displayed spin polarized band structures. During spin down band, TiO2 doped gamma-graphyne carries similar to 0.7 eV band gap having n-type dopant nature. Similarly, during spin up channel, TiO3 doped gamma-graphyne carries similar to 0.9 eV direct band gap semiconductor behavior. Blue shift appears in absorption and extinction coefficient plots after TiOx substitution in gamma-graphyne. Likewise, static reflectivity and refractive index parameters are improved having maximum of 0.65 and 8 peak intensities, respectively. Our obtained results suggest a viable way forward for making functional hybrid gamma-graphynes to be used in opto-electronic and spintronic device applications.

Automated summary

The study investigated the effects of TiOx doping on the structural, opto-electronic, and spintronic properties of γ-graphyne. It was found that TiO2(3) doping can transform nonmagnetic graphynes into magnetic materials with spin polarized band structures. TiO-doped graphynes exhibit nonmagnetic narrow band indirect semiconductor behavior, and a blue shift in absorption and extinction coefficient.