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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 LaAl[O.sub.3] 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 LaAl[O.sub.3]. 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. Key words: band structure, density of states, optical properties, refractive index, elastic and mechanical properties, 1. Introduction To solve a variety of challenges, including the use of power and energy, scientists are developing new strategies and insights. Different theoretical and experimental methods have been established [...]

Utilization of waste pollution to solve electromagnetic waves pollution is a good strategy towards a green future. In this study, we have used two different biowastes, wheat stubble and peanut hulls, as biocarbon sources to obtain two diverse inherited morphologies, i.e., sheet-like morphology from wheat stubble and distorted/ripped biocarbon morphology from peanut hulls. Detailed microwave absorption characterization analysis shows that the distorted/ripped morphology has better reflection loss and effective absorption bandwidth (EAB) as compared to the sheet-like morphology. Furthermore, MnFe 2 O 4 particles are also used to get composites with both types of biocarbon. The minimum reflection loss (RLmini) value achieved by the ripped biocarbon/ MnFe 2 O 4 is − 40.6 dB, with EAB being 5.6 GHz (13.2–7.6 GHz). Our findings show that better microwave absorption performance is attributed to the distorted/ripped morphology and by biocarbon– MnFe 2 O 4 synergetic influence. These findings open a route for biowaste and magnetic waste to be used in controllable microwave absorption applications. [ABSTRACT FROM AUTHOR]

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]

Among an extensive range of materials, biocarbon has acquired considerable interest because of its superiority of wide absorption bandwidth, strong absorption, accessibility, cost-effective and eco-friendly. Here, the inherited morphology of the biocarbon has been utilized to tune the performance of the microwave absorber. Biocarbon (wheat straw & peanut shells) and industrial waste (MnFe2O4) have been used to fabricate microwave absorption composites. Biocarbon wastes with two different morphologies, sheetlike and distorted, have been used to prepare the composites. Composite with sheetlike morphology attained the minimum reflection loss (RLmini) of − 19 dB but, on the other hand, composite with distorted morphology achieved RLmini of − 43 dB, as well as, it is the effective absorption bandwidth (EAB) covers the whole X-band. Our findings reveal that microwave absorption performance of the absorbers strongly relies on the anisotropic morphology of the biocarbon. It is expected that composites with anisotropic morphology of the biocarbon may be utilized to modify microwave absorption performance for practical applications. [ABSTRACT FROM AUTHOR]