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[Display omitted] • The materials are stable in their cubic structure. • All materials exhibit indirect bandgaps. • The optical properties depict that the materials are suitable for photovoltaic applications. • The thermoelectric properties give valuable insight into thermoelectric efficiency of the examined materials. In this study, we employed density-functional theory (DFT) to investigate the structural, electrical, thermodynamic, optical, and thermoelectric characteristics of Na 2 ScAgZ 6 (Z=Br, I). The Goldschmidt tolerance factor (τ), formation energy, and Gibbs free energy values reveal a high level of thermodynamic and structural stability. Additionally, the thermodynamic stability of the explored double perovskites Na 2 ScAgZ 6 (Z=Br, I) has been verified by employing ab initio finite temperature molecular dynamics simulation. An indirect bandgap of 2.01 eV (Na 2 ScAgBr 6) and 0.95 eV (Na 2 ScAgI 6) is found using TB-mBJ approximation. This is an essential parameter for photovoltaic applications. The bandgap values of these compounds show that they absorb the majority of radiation in the visible region; thereby substituting bromide with iodide causes a decrease in the bandgap. The current investigation aims to study the absorption of light energy, polarization, refractive index, and energy loss across the energy ranges from 0 to 6 eV. The dielectric constant has been looked at to identify the highest absorption of incident light in the visible area. The optical characteristics are suitable for use in photovoltaic appliances as the absorption takes place in the visible range. Using the BoltzTraP code, the thermoelectric properties are evaluated and found that the highest ZT values are 0.78 (Na 2 ScAgBr 6) and 0.92 (Na 2 ScAgI 6), respectively. This indicates that these materials can be viable alternatives for photovoltaic and thermoelectric devices. [ABSTRACT FROM AUTHOR]

The magnesium based spinel chalcogenides are outstanding materials for spintronic technology and energy applications. Herein, the modified Becke Johnson potential (TB-mBJ) was employed to investigate the electrical, ferromagnetism, and thermoelectric properties of MgDy 2 (S/Se) 4 spinels comprehensively. The energy emitted during optimization as well as formation energy has both been used to demonstrate the stability of the cubic phase. The density of states, Curie temperature, exchange coupling, and spin polarization are elaborated to address the nature of ferromagnetism. Further, half metallic ferromagnetism is studied in terms of hybridization, exchange energies, and exchange constants. In contrast to the clustering effect of the internal magnetic of Dy atoms in the structure, the lowering of Dy's magnetic moment and its transferring on Mg, and S/Se sites demonstrate that the ferromagnetism is caused by the exchange of electron spin. Furthermore, thermoelectric properties were studied and various thermoelectric parameters such as electrical and thermal conductivities, Seebeck coefficient (S), and power factor (PF) of the examined spinels have been determined. • Above room temperature ferromagnetism, and spintronic applications. • Quantum spin of electrons dominant the charge with multifuctional properties. • Exchange mechanism certifies the ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism and 100 % spin polarization. • Large value of electrical conductivity and ultralow low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

The spintronic is an emerging technology which controls the properties of multifactional devices with spin of electrons. In present manuscript, Wien2k and Boltz Trap codes are used to explore electronic, magnetic, and thermoelectric characteristics of Sr 2 CrXO 6 (X = Nb, Mo) double perovskites (DPs). The evaluation of energies released in paramagnetic (PM), antiferromagnetic (AFM), and ferromagnetic (FM) states assure the stability of FM states. Both the negative formation energy and the tolerance factor confirm structural and thermodynamic stability in FM states. The 100 % spin polarization was confirmed by both integer values of magnetic moment (MM) and the spin polarization factor. The values of exchange energy, double exchange model, hybridization of p-d states, and exchange constants are calculated to explore the nature of ferromagnetism and spin functionality. The effect of thermoelectric parameters on spin of electrons and thermoelectric performance are elaborated by thermal to electrical conductivity ratio, Seebeck coefficient and power factor. • High Curie temperature, and spintronic applications. • Spin of electrons overcome the charge with multifuctional properties. • Double exchange mechanism confirms the ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism and 100 % spin polarization. • Large value of electrical conductivity and low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

Copper sulphide (Cu x S) thin films were deposited by the spin coating method using copper acetate (Cu₂(CH₃COO)₄) and thiourea (CH₄N₂S) as precursors. This simple technique was shown to produce thin films with high quality in terms of tunable stoichiometry and physical properties. In fact, the room temperature structural, optical and thermoelectric properties were studied. It is observed that the annealing during 1 h at 250 °C and 300 °C results in the transition from the covellite (CuS) to the chalcocite (Cu 2 S) and djurleite (Cu 1.95 S) phases, respectively. Optical measurements show the formation of absorbing films in the visible range with a transmittance lower than 50 % for all phases. The covellite phase is found to be thermoelectrically interesting with a power factor of 12.3 μWK−2m−1, while the conductivity of the djurleite phase (281.7 Ω−1cm−1) needs to be improved to match its high Seebeck coefficient (21.3 μVK−1). [ABSTRACT FROM AUTHOR]