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The change in composition and pressure, both of which lead to new desired properties by altering the structure, is particularly important for improving device performance. Given this, we focused here on the mechanical, elastic, and optoelectronic characteristics of the Cd0.75Zn0.25Se alloy using density functional theory at various pressures from 0 GPa to 20 GPa. It is found that the bulk modulus of the material rises with increasing pressure and exhibits mechanical stability as well as cubic symmetry. In addition, the increased pressure leads to a rise in the direct bandgap energy of the material from 2.03 eV to 2.48 eV. The absorption coefficient of the alloy also increases as the pressure increases, where the effective range of absorption covers the broad spectrum of light in the visible range from orange to cyan. This is due to the electronic transitions caused by the altered pressure. The optical parameters, including optical conductivity, extinction coefficient, reflection, and refractive index, are also analyzed under the influence of pressure. Based on this research, effective applications of the Cd substituted Zn-chalcogenides (CdZnSe) alloys in the fields of optoelectronics and photovoltaics are outlined, especially concerning fabricating solar cells, photonic devices, and pressure sensors for space technology.
RESUMO
This study explores the nuclear magnetic shielding, chemical shifts, and the optoelectronic properties of the BiMnVO5 compound using the full-potential linearized augmented plane wave method within the generalized gradient approximation by employing the Hubbard model (GGA + U). The 209Bi and 51V chemical shifts and bandgap values of the BiMnVO5 compound in a triclinic crystal structure are found to be directly related to Hubbard potential. The relationship between the isotropic nuclear magnetic shielding σiso and chemical shift δiso is obtained with a slope of 1.0231 and - 0.00188 for 209Bi and 51V atoms, respectively. It is also observed that the bandgap, isotropic nuclear magnetic shielding, and chemical shifts increase with the change in Hubbard potentials (U) of 3, 4, 5, 6, and 7.
RESUMO
The structural and optoelectronic characteristics of Zn1-x Cd x S (x = 0, 0.25, 0.50, 0.75, 1) semiconductors are reported using density functional theory within GGA, EV-GGA, and mBJ functionals. These semiconductors are observed in cubic symmetry at all Cd-concentrations and the lattice constant increases linearly with Cd-concentration while the bulk modulus shows a reverse behavior. These materials are direct bandgap semiconductors at all Cd-concentrations and their bandgap energy decreases from 3.67 eV to 2.59 eV. The isotropic optical properties of these direct bandgap semiconductors vary with Cd concentration as well, with absorption coefficients decreasing and absorbed near-UV light converting to visible blue light. Optical properties like refractive index, dielectric constant, conductivity, extinction coefficient, and reflectance are also displayed and discussed. These results provide useful theoretical understanding for the application of CdZnS semiconductors in photonic, photovoltaic, and optoelectronic devices.
RESUMO
[This corrects the article DOI: 10.1039/D2RA03850A.].