Band Structure Engineering and Optical Properties of Pristine and Doped Monoclinic Zirconia (m-ZrO₂): Density Functional Theory Theoretical Prospective

Abstract

Recently, monoclinic ZrO 2 has received great technological importance because of its remarkable dielectric properties, high chemical stability, and high melting point. Herein, we introduce first-principles calculations using the Hubbard approach (DFT + U) to study the effects of doping with Nb and W on the electronic and optical properties of pristine ZrO 2 . The introduction of dopant atoms into the pristine crystal structure led to the displacement of the bandgap edges and reallocation of the Fermi level. The valence band maximum (VBM) shifted upward, resulting in band gap tightening from 5.79 to 0.89 for ZrO 2 : Nb and to 1.33 eV for ZrO 2 : W. The optical absorption of doped crystals extended into the visible and near-infrared regions. Partial density of states (PDOS) calculations showed valence band dependency on the O 2p orbital energy, with the conduction band predominantly composed of Nb 4d and W 5d. For pristine ZrO 2 , the results obtained for the imaginary and real parts of the dielectric function, the refractive index, and the reflectivity show good agreement with the available experimental and theoretical results. For ZrO 2 :W, we checked the dopant location effect, and the obtained results showed no significant effect on the calculated values of the band gap with a maximum difference of 0.17 eV. Significant band gap tightening and optical properties of our systems indicate that these systems could be promising candidates for photoelectrochemical energy conversion (PEC) applications.

Biomimmetic ZrO 2 @ PdO nanocomposites: fabrication, characterization, and water splitting potential exploration

“…The energy value of band ZrO (5.0 eV) narrowed when it was doped with PdO, which depicted the charge transfer ability of the material. The spectra show the percentage of energy lost by an electromagnetic wave as it passes through a material 57 The spectral result of ZrO2 doping is in good agreement with the result of Khattab et al, 58 in which the absorption edge is recorded at wavelengths ranging from 200 to 650 nm. Because of the increased interactions between electrons and photons in doped systems, the incorporation of Pd increased optical absorption in the visible and near-infrared regions, which corresponds to a higher dielectric of the imaginary part at zero voltage.…”

Tunable Negative Differential Resistance Effect in a-SZTO/Dielectric/SZTO Heterostructure TFTs at Room Temperature

“…This result may be due to the low band gap value of HfO 2 compared to other materials of ZrO 2 and MgO. The band gap values of HfO 2 , ZrO 2 , and MgO are ∼5.5, ∼5.8, and ∼7.7 eV, respectively. − …”

Revealing the electronic, optical, elastic, mechanical, anisotropic, and thermoelectric responses of Sc2NiZ (Z = Si, Ge, and Sn) Heusler alloys via DFT calculations

“…Moreover, the refractive index ( n ) indicates the light‐speed change between a vacuum and a denser medium. The extinction coefficient ( k ) is directly proportional to absorption and explains how fast light vanishes in a material [24–26]. Figure 4 displays the refractive index curves of Sc 2 NiZ (Z = Si, Ge, and Sn) alloys.…”