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In this study, we used density functional theory to examine how the wide band gap optoelectronic properties of pure, silver-, and cadmium-doped LaAlO3 perovskites changed. Structural, electrical, elastic, and mechanical properties were calculated using generalized gradient approximation. Silver and cadmium incorporated at Al site demonstrated a decreasing trend in the band gap. Both impurities showed the reduction in band gap from 2.98 to 0.468 eV and from 2.98 to 2.0238 eV. The density of states was examined for pristine and doped structures to understand behavioral change of LaAlO3. It was observed that p states in upper valance band and d states in lower conduction band were contributing toward the reduction of band gap. Elastic properties were computed. Elastic parameters were used to calculate Born's stability and it is predicted that the material is stable mechanically for both pristine and doped forms. Mechanical properties were also predicted and brittle nature was found for both pristine and doped materials. Optical responses such as dielectric function, absorption, and refractive index were also predicted. The impurity inclusion in pristine structure not only reduces the bad gap but also alters the optical behavior. Absorption edge shifted toward lower energy shows a clear redshift, whereas refractive index also reduces from 2.4 to 1.9, making the material more transparent. The absorption spectrum as well as electronic band gap makes this material more useful for solar cell application as well as photocatalytic applications. [ABSTRACT FROM AUTHOR]

This study explores the optoelectronic potential of advanced perovskite materials, with a primary focus on alloying KMgF 3 with 3d transition metals. Through this alloying process, the study employs density functional theory (DFT) with the GGA-PBE functional to tailor the atomic structure and various properties, including optoelectronic, mechanical, acoustic, anisotropic, and photocatalytic attributes. The introduction of Zn to KMgF 3 triggers a noticeable bandgap redshift and significant improvements in mechanical stability and photocatalytic performance. Increasing Zn content induces a transition in KMgF 3 's crystal structure to a pseudo-cubic tetragonal form, which remains mechanically stable for both pristine KMgF 3 and KMg (1-x) Zn x F 3. Zn inclusion introduces versatile nonlinearity in terms of brittleness, stiffness, mechanical strength, and thermal behavior. This comprehensive analysis underscores anisotropy, mixed bonding, Debye fluctuations, and melting temperature variations. Notably, among the systems examined, KMg 0.25 Zn 0.75 F 3 stands out as an outstanding candidate for applications in photovoltaics and water splitting, thanks to its exceptional optical performance. • Mechanical properties of pristine and Zn doped KMgF 3 are investigated. • Results indicated that KMg (1-x) Zn x F 3 can exist in layered configuration. • 3d TM inclusion in KMgF 3 tuned the electronic band gap while preserving its indirect nature. • Photocatalytic Performance improved upon doping due to band gap reduction. [ABSTRACT FROM AUTHOR]

The structural, optoelectronic, and photocatalytic properties of KCaF 3-x Br x , where x indicates Br concentration (x = 0, 0.6, 1.2, 1.8, 2.4, 3.0), are described here using density functional theory. Computed structural and optoelectronic results for pristine c-KCaF 3 are well consistent with existing literature. Bandgap was engineered by impurity inclusion such that the proposed material changes its bandgap for both generalized gradient approximation (GGA) and Heyd, Scuseria, and Ernzerhof hybrid functional (HSE03) formalism from 5.638 eV to 3.807 eV and from 8.538eV to 2.772 eV respectively. One of the most important criteria for proposing a new end material is structural and mechanical stability, thus the tolerance factor and Born's requirements were used to establish the end materials' stable cubic nature. Optical parameters such as dielectric function, reflection and absorption coefficient, refractive index, and energy loss function are calculated and analyzed up to the photon energy range of 0–35 eV. A redshift was observed whereas the refractive index values for different concentration shows continuous change except for x = 2.6. The highest value of reflectivity is observed for KCaBr 3 making it useful for several thermoelectric applications. Photocatalytic properties were predicted using a band edge diagram, indicating that the presented series of materials is a useful candidate for hydrogen evolution reaction (HER), and oxygen evolution reaction (OER). Br substitution at the anionic site of c-KCaF 3 has been reported first ever, with promising optical, elastic, and photocatalytic properties that will inspire further research on this material. [ABSTRACT FROM AUTHOR]

• A theoretical study was carried out to explore the effect of Cd in BaZrO 3 (BZO). • Pure BZO shows a 3.114 eV bandgap whereas the new end material CdZrO 3 shows a 0 eV bandgap. • At 100% substitution of Cd, BZO showed conducting behavior. • The bandgap and optical responses are tunable. • Photocatalytic and mechanical properties are explored. First principle calculations are taken into account to investigate different properties like overall water splitting, elastic, mechanical, optical, electronic, and structural, of pure along with cadmium-induced BaZrO 3 which is an oxide-based perovskite. Ultra-soft pseudo-potential is integrated within Cambridge Serial Total Energy Package to explore these properties. Generalized gradient approximation suggested by Perdew-Burke Erzenhoff and hybrid functional is taken into account for exchange–correlation potential. Cadmium introduced at Ba site is more successful rather than Zirconium as brand new gamma points appeared that also influenced the electronic formation of pure BZO minimized band gap from 3.114–0 eV and 4.203–0.470 eV by using GGA-PBE and HSE03 respectively. In Cd substitution case, Fermi level shifted to near valence band which reveals property of semiconductor material called p-type before showing conducting behavior at full replacement of Ba with Cd. Furthermore, mechanical properties derived from elastic constants i.e. Bulk modulus, Shear modulus, Young modulus, Poisson ratio, and finally these materials were established to justify born stability requirements. In addition, Cauchy's pressure along with Pugh's ratio also proved brittle nature of these material compositions. We explored and compared optical properties for example absorption spectra, refractive index (3.1), dielectric function, and reflectivity, as an energy loss function of pure BZO in comparison with Cd loaded BZO. Cd based BZO transforms optical performance considerably therefore this material is more effective for optoelectronic devices. Overall water splitting was studied for pure and Cd substituted BaZrO 3. The pure and two and Six atoms doped material play a vital role for overall water splitting. It is proposed that the said materials are not only lead free for green energy applications in photocatalytic activity but also that the bandgap range is suitable for solar cell applications. [ABSTRACT FROM AUTHOR]

The structural, mechanical, and opto-electronic properties of cubic RbCdF 3 (c-RCF) under high pressures were probed using a Generalized-Gradient Approximation (GGA-PBE) within the fram work of CASTEP. The aim of this study is to see how pressure affects structural and electronic properties and in response of electronic change how optical behaviour altered along with mechanical properties. The calculated structural properties such as the equilibrium lattice parameter (4.59 Å), the bulk modulus (63.7821) and its pressure derivative are in good agreement with the available data at pressure 0 GPa. The obtained results for the band structure and the total density of states (TDOS) show that the RbCdF 3 has an indirect band gap of 2.863 eV. The changing electronic properties affect optical response which was studied and discussed. The refractive index (n(ω)) decreases from 2.6 to 1.72 gradually with increasing pressure. The elastic constants were calculated using the energy deformation relationship, from these constants the other mechanical properties such as bulk modulus, shear modulus, Young modulus and Poisson ratio were calculated and commented. The results of elastic constants established that RbCdF 3 is mechanically stable at each pressure because it fulfills the Born's stability criteria. RbCdF 3 behaves as brittle at low pressure when we increased pressure it shows ductile nature in this study. Poisson ratio (σ) and Cauchy pressure also confirm similar behaviour. Lastly, the anisotropy factor was discussed. RCF is thus a fascinating material for optoelectronic devices, thermoelectric and piezoelectric properties. • The structural, mechanical, and opto-electronic properties of cubic RbCdF 3 (c-RCF) under high pressures were probed. • The calculated structural properties such as the equilibrium lattice parameter (4.59 Å), the bulk modulus (63.7821) and its pressure derivative are in good agreement with the available data. • The RbCdF 3 has an indirect band gap of 2.863 eV. • The refractive index (n(ω)) decreases from 2.6 to 1.72 gradually with increasing pressure. • The results of elastic constants established that RbCdF 3 is mechanically stable at each pressure. [ABSTRACT FROM AUTHOR]