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Context: Depletion of natural resources, responsible for energy production, is a serious concern for researchers to develop alternate energy resources or materials. Scientists have proposed various energy materials which are based on semiconductors and their underlying physics. Cerium oxide (CeO2) is a versatile energy material which receives much attention owing to excellent photocatalytic, photonic, thermal stability, and optoelectronic applications. Even though CeO2 exhibited remarkable physical properties, but yet, they can be enhanced upon suitable doping. Focus on current research is to dope group V elements into CeO2 in order to enhance its electronic and optical response. The density of states (DOS) and band gaps of proposed materials are calculated, and significant improvement is noted after applying TB-mbj method. Optical absorption spectra of V/Nb/Ta-doped CeO2 show blueshift and decrease in reflectivity along with the presence of magnetism illustrate potential uses of these materials in future UV optoelectronics, spintronics, sensing, and energy harvesting devices. Methods: This research is based on computational work carried using Wien2k code where PBE-GGA approximation is used to approximate exchange and correlation potentials. Supercells of vanadium/niobium/tantalum-doped CeO2 are constructed, and spin-polarized density of states (DOS) along with optical constant are calculated. TB-mbj method is used to bring improvements in DOS and band gaps of proposed materials. Iterations are conducted using convergence criterion, and non-relativistic calculations are performed. [ABSTRACT FROM AUTHOR]

Current research elucidate investigations on calculating the structural, electronic, magnetic, and optical properties of Mo/Cr doped CeO 2 and Mo-Cr co-doped CeO 2 using the Wien2k code. The exchange-correlation functional is approximated using the PBE-GGA approximation. Spin-polarized DOS present the magnetic character of proposed materials. A higher magnetic moment (3.749 μ B) is noticed for Mo-Cr@CeO 2 while lower magnetic moment (2.247 μ B) is observed for Mo@CeO 2 material. The Ce 4 f -, O 2 p -, Mo 3 d -, and Cr 3 d -states appreciably tune electronic properties. Absorption spectra of Mo@CeO 2 and Mo-Cr@CeO 2 materials exhibit blueshift, while Cr@CeO 2 material shows redshift. Curie temperature indicates spintronic applications of these materials. Enhanced conductivity, improved dielectric response, and decreased reflectivity of proposed materials in the UV region implicate their uses in high-frequency UV optoelectronics, photovoltaics, spintronics, photonics and capacitive devices. • Structural, electronic, magnetic, and optical properties of Mo/Cr@CeO 2 and Mo-Cr @CeO 2 were performed using Wien2k. • Electronic properties were modified with Ce 4 f -, O 2 p -, Mo 3 d -, and Cr 3 d -states along with p - d hybridization. • Magnetic moment values of Mo/Cr@CeO 2 and Mo-Cr@CeO 2 were noted to be 2.247/2.305 μ B and 3.749 μ B , respectively. • Mo@CeO 2 and Mo-Cr@CeO 2 have blueshift while Cr@CeO 2 exhibited redshift in absorption. • Blueshift and magnetism illustrated uses of Mo/Mo-Cr@CeO 2 materials for UV optoelectronic, photonics, photovoltaics, and spintronic devices. [ABSTRACT FROM AUTHOR]

This research explores the structural, electronic, magnetic, and optical properties of GaN-X (X = Sr, Ba, Cs, Mg) materials. First principle calculations based on full potential linearized augmented plane wave (FP-LAPW) method is executed in Wien2k code. PBE-GGA approximation is used to approximate exchange-correlation functional. Sr 3 d -states, Ba 5 p -states, Cs 5 p -states, and Mg 2 p -states help in improving electronic properties. The magnetic character of the proposed materials is revealed with net magnetic moment values of, 2.9639 μ B , 2.3316 μ B , 3.4179 μ B , and 3.1697 μ B , respectively. Optical absorption shows blueshift for Ba@GaN and Mg@GaN while Sr@GaN and Cs@GaN spectra show redshift. Absorption and conductivity are enhanced in the UV region, along with decrease in reflectivity. Optical response of proposed materials illustrate to make use of these materials for production of high energy UV optoelectronics, photonics, memory, spintronics and photovoltaic devices. [ABSTRACT FROM AUTHOR]

Current research is based on density functional theory investigations of structural, electronic, magnetic, and optical properties of X (X = Sm, La, Ce) doped CdS using Wien2k code. Spin-polarized calculations indicate non-magnetic character of pure and La doped CdS while magnetism is noticed upon Sm and Ce doping into CdS. Hubbard correction indicate shift of f -states toward the Fermi level and non-negative frequency modes in phonon spectra illustrate dynamical stability of proposed materials for synthesis. However, magnetic moment in Ce doped CdS (2.9188 μ B) is larger than Sm doped CdS (2.7901 μ B). Cd 4 d -states, S 3 p -states, La 5 d -, Sm and Ce 4 f -states show supreme role around the Fermi level which improve electronic properties. Reduction in band gap is noted which points good conduction. Optical absorption spectrum of impurities added CdS materials exhibit blueshift. Moreover, enhanced absorption and upgraded conductivity along with increasing refractive index of selected materials emphasize their potential uses in high energy UV photonics, sensors, spintronics, optoelectronics and energy harvesting devices. • Electronic, structural, magnetic, optical properties, phonon dispersion and band gap of Sm/La/Ce doped CdS were calculated using Wien2k. • Electronic properties have been studied with and without Hubbard correction. • Phonon spectra exhibited positive frequency modes. • Band gap was reduced with impurities addition into CdS. • Absorption spectra of proposed materials have shown blueshift in comparison to pure CdS. • Enhanced absorption and conductivity in the UV and visible region have illustrated potential uses of proposed materials in optoelectronics, photonics, and spintronics applications. [ABSTRACT FROM AUTHOR]

We investigate electronic, optical and magnetic properties of Al and Ga doped CeO 2 using first principle calculations. In order to approximate exchange and correlation potential, Perdew-Burke-Ernzerhof (PBE) based generalized gradient approximation is used in Wien2k code. Spin-polarized calculations manifest non-magnetic nature of CeO 2 while Al and Ga doped CeO 2 points magnetic character with net magnetic moment of 3.09 μ B and 2.03 μ B , respectively. p - d hybridization with enormous influence of Ce 4 f -, Al 3 p - and Ga 3 d -states is noted which tune electronic properties of selected materials. Optical absorption spectrum of pure CeO 2 shows blueshift upon incorporation of impurities. Upon addition of impurities, significant reduction in band gap of CeO 2 is noted. Improved absorption and conductivity along with decrease in reflectivity in the UV region embellish uses of these materials in the field of optoelectronics, photonics, solar, photocatalysis and spintronics. [Display omitted] • Electronic, magnetic, and optical properties of Al:CeO 2 and Ga:CeO 2 were performed using Wien2k. • Electronic properties were modified with Ce 4 f -, Al 3 p - and Ga 3 d -states along with p - d hybridization. • Al and Ga doping brings magnetism into CeO 2 with magnetic moment of 3.0518 μ B and 2.0422 μ B , respectively. • Adding impurities (Al, Ga) into CeO 2 have caused blueshift in absorption spectrum. • Blueshift and magnetism of Al:CeO 2 and Ga:CeO 2 points their potential applications in current optoelectronics, photovoltaics, photonics, and spintronics. [ABSTRACT FROM AUTHOR]

This research presents detailed investigations of the structural, electronic, magnetic and optical properties of cesium doped and Cs-X (X = Mn, Fe) co-doped CdS. We employ Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation within Wien2K code. Cs-X (X = Mn, Fe) co-doped CdS materials exhibit magnetic moment and thus, show magnetic character. Role of 5 p -states of Cs atom and 3 d -states of Mn, Fe atoms appreciably tune the electronic properties. Optical absorption spectrum of Cs@CdS shows blueshift while Cs–Mn/Fe co-doping into CdS causes redshift. However, the ability of proposed materials to absorb electromagnetic radiations in the 0–7 eV energy range and presence of the magnetism illustrates their potential uses for fabrication of novel optoelectronic and spintronic devices. [Display omitted] • Structural, electronic, magnetic, and optical properties of pure CdS, Cs@CdS and Cs–Mn/Fe@CdS were calculated using DFT. • Cs doped CdS is non-magnetic while Cs–Mn/Fe caused magnetism into CdS. • Blueshift in absorption spectrum of Cs@CdS enable its uses in UV optoelectronics while absorption of Cs–Mn/Fe@CdS was red shifted. • Phonon dispersion illustrates absence of negative frequency, indicating materials stability. • Ability of materials to absorb electromagnetic radiations and magnetism indicate their uses for uses in novel optoelectronic and spintronic devices. [ABSTRACT FROM AUTHOR]