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The current study utilized DFT (density functional theory) calculations to examine the influence of Ca-doping on the optoelectronic properties of Ra0.875Ca0.125TiO3 (RCT12), Ra0.75Ca0.25TiO3 (RCT25), and Ra0.625Ca0.375TiO3 (RCT37). We utilize the FP-LAPW + lo (full potential linearized augmented plane wave plus local orbital) method in order to solve the Kohn–Sham equations using the generalized gradient approximation (GGA). The GGA model along with Hubbard potential (GGA + U) is utilized to compute fundamental properties of the studied perovskites. The energy bandgap values for RCT12, RCT25, and RCT37 are around 1.96, 1.92 and 1.87 eV, respectively. From the obtained ε 2 (ω) spectra, it is evident that RCT12, RCT25, and RCT37 compounds shows a substantial absorption of incoming photons in the visible and near UV region. The computed values of n (ω) for RCT12, RCT25, and RCT37 are 1.79, 1.77 and 1.76, respectively. The aforesaid compounds having n (ω) values in the range of 1.0 and 2.0 are regarded as active optical materials. The optoelectronic characteristics of RCT12, RCT25, and RCT37 suggest that they have promising potential for use in energy-related applications like solar cells. [ABSTRACT FROM AUTHOR]

The current investigation employs first‐principles DFT (density functional theory) calculations to examine the influence of transition metal replacements on the structural, thermodynamic, and thermoelectric properties of Cu‐based chalcogenides TMCu3Se4 (TM = Nb/Ta/V). The PBE‐generalized gradient approximation (GGA) model is utilized to compute the fundamental properties of Cu‐based chalcogenides under study. A thorough examination of the energy band structures indicates that these chalcogenides are semiconductor compounds with indirect energy bandgaps. We can infer from the calculated energy band structures that the bandgap values are 1.67, 1.77, and 1.05 eV for NbCu3Se4, TaCu3Se4, and VCu3Se4, respectively. The ZTe$$ {\mathrm{ZT}}_e $$ values for NbCu3Se4, TaCu3Se4, and VCu3Se4 are 0.661, 0.998, and 0.996, respectively. These values make them highly appropriate for usage in thermoelectric (TE) devices. The thermoelectric characteristics of pyrochlore oxides TMCu3Se4 (TM = Nb/Ta/V) suggest that these materials have promising potential for energy‐related applications. The analyzed thermodynamic properties demonstrate that the Cu0based chalcogenide materials TMCu3Se4 (TM = Nb/Ta/V) exhibit a notable level of thermal stability. [ABSTRACT FROM AUTHOR]

Lead‐free double perovskites are now assumed to be suitable candidates for green energy harvesting in particular as active materials for solar cells and thermoelectric generators, which can meet future generation energy needs. Therefore, we explore the Au‐based halide double perovskites X2Au+Au3+Br6 (X = Cs, Rb) from the first principles approach. Density functional theory (DFT) is utilized to explore the electronic structure with DFT code Quantum ESPRESSO. The mechanical, thermodynamic, and structural stability is ensured from Burn‐Haun criterion, formation energies, and Goldschmidt factors, respectively. The examined materials have stable structures with direct band gaps i.e. 1.54 and 1.72 eV. The existence of band gaps in the visible region motivates us to explore the optical properties, which give fascinating outcomes. The absorption coefficients and optical conductivity peaks are found to be significant in the visible region i.e., ≈104 cm−1 and ≈1015 s−1, respectively. Additionally, the thermoelectric properties are also investigated using Boltzmann transport theory. There are several good gestures for the usage in the thermoelectric generators since the values of Seebeck coefficients (446.5, and 225.2 μV K−1), power factors (1.75 × 1011 W mk−2 s, and 1.24 × 1011 W mk−2 s), and figure of merits (0.92 and 0.73) are noteworthy for Cs2AuAuBr6 and Rb2AuAuBr6, respectively, at room temperature T = 300 K. [ABSTRACT FROM AUTHOR]

Introduction: Scientific evidence about biological profile of natural products can support their traditional uses. The current work was aimed to assess phytochemical and biological profile of nine medicinal plants collected from Herbalists. Methods: Extracts prepared in different solvents were subjected to phytochemical, antioxidant, enzyme inhibitory, cytotoxic, and antimicrobial activities. Reverse phase-high performance liquid chromatography (RP-HPLC) analysis was performed for the quantification of polyphenols. Results: Results showed methanol extract (M) being potent as compared to others. Gentian lutea M showed maximum extract recovery (15.00 ± 0.11 % w/w) and TFC (30.82 ± 0.21 μg QE/mg extract). Nigella sativa M displayed highest TPC (44.99 ± 0.43 μg GAE/mg extract) and TAC (334.72 ± 0.35 μg AAE/ mg extract). Results showed noteworthy quantities of vanillic acid, rutin, kaempferol, emodin in ethyl acetate (EA) and methanol (M) extracts of plants assessed by RP-HPLC. Gentisic acid was highest (11.75 µg/mg extract) in T. arjuna M extract. Similarly, maximum %FRSA (82.28 ± 0.03 %) and TRP (160.40 ± 0.38 μg AAE/ mg extract) were depicted by Terminalia chebula and Chamomilla recutita, respectively. Moreover, Mentha longifolia and G. lutea M demonstrated noteworthy (p

In order to address the energy challenges of the near future, researchers are currently focused on developing environmentally friendly and energy-efficient phosphors for luminescence devices such as light-emitting diodes (LEDs). When it comes to this topic, older lighting devices such as halogen lamps, LCD backlights, incandescent lamps, and fluorescent lamps can be substituted with advanced next-generation lighting technology created with phosphor-transformed white LEDs. We've conducted a detailed analysis of the structural and optoelectronic characteristics of Cs-based phosphors Cs2MF6 (M = C, Ge, Pb, Si) for potential use in photoluminescence as well as photovoltaic applications such as LEDs. Utilizing the GGA scheme allows for an in-depth analysis of exchange and correlation energy potentials within density functional theory (DFT) first-principles calculations. The calculated structural properties reveals that Cs2PbF6 is the most stable compound among Cs2MF6 (M = C, Ge, Pb, Si) as they possess lowest ground state energy. Direct bandgaps of 1.57, 1.459, 1.481, and 1.59 eV are observed with the presence of intermediate bands for Cs2CF6, Cs2GeF6, Cs2PbF6, and Cs2SiF6, respectively. It is established by analyzing plots that the investigated hexafluorides absorb maximum photons in the UV region. Based on the spectra, it is evident that Cs2MF6 (M = C, Ge, Pb, Si) act as weak reflectors of incident photons in the visible and IR regions. However, around 40% of the incoming photons get reflected at various energies by individual compounds. Thermodynamic characteristics of these hexafluorides reveals that they are thermodynamically stable compounds. [ABSTRACT FROM AUTHOR]

One of the primary objectives of scientific research is to create state-of-the-art multiferroic (MF) materials that exhibit interconnected properties, such as piezoelectricity, magnetoelectricity, and magnetostriction, and remain functional under normal ambient temperature conditions. In this study, we employed first-principles calculations to investigate how changing pnictogen elements affect the structural, electronic, magnetic, and optical characteristics of QFeO3 (Q = Bi, P, SB). Electronic band structures reveal that BiFeO3 is a semiconductor compound; however, PFeO3 and SbFeO3 are metallic. The studied compounds are promising for spintronics, as they exhibit excellent magnetic properties. The calculated magnetic moments decreased as we replaced Bi with SB and P in BiFeO3. A red shift in the values of ε 2 (ω) was evident from the presented spectra as we substituted Bi with Sb and P in BiFeO3. QFeO3 (Q = Bi, P, SB) showed the maximum absorption of incident photons in the visible region. The results obtained from calculating the optical parameters suggest that these materials have a strong potential to be used in photovoltaic applications. [ABSTRACT FROM AUTHOR]