Search

Spinel chalcogenides have great potential for optoelectronic and thermoelectric applications and therefore received huge attention in recent years. In this regard, here we investigate the structural, optical, electronic, and thermoelectric characteristics of HgY2S4and HgY2Se4spinel chalcogens using a density functional theory-based WIEN2k package. Ground state optimization of crystal structure and thermodynamic stability of the material is probed from the energy volume optimization graph and computation of enthalpy of formation. The computation of Poisson's and Pugh's ratios revealed the ductile nature of these materials. Bandgap calculation is performed using TB-mBJ package, which exposed the direct band nature of these semiconducting materials with bandgap values of 1.2 eV for HgY2S4and 0.6 eV for HgY2Se4. The evaluation of optical characteristics and transport features revealed these compositions’ potential for optoelectronic and thermoelectric applications.

Double perovskite (DP) halides are a reliable source of renewable energy that plays a vital role to fulfill the requirements of energy crunch. Therefore, the analysis of these perovskite halides have promising uses for thermoelectric and optoelectronics purposes. We investigated the thermoelectric and optoelectronics properties of Rb2KScI6and Cs2KScI6halides for use in renewable energy devices by using FP-LAPW + lo approach based on DFT. The calculated Goldsmith's tolerance factor and enthalpy of the formation of studied halides reveal that these are structurally and thermodynamically stable in cubic phase. Moreover, the analyzed value of Poisson and Pugh ratio reveals ductile nature of these materials. Further, we computed the bandgaps by analyzing electronic characteristics. For bandgap calculations of Rb2KScI6(Eg = 2.75 eV) and Cs2KScI6(Eg = 2.65 eV), we employed mBJ potentials to obtain precise values as comparison to experimental values. The complex dielectric function used to reveal the optical properties of the analyzed materials. The calculated optical results clearly show the maximum absorption of light in infrared (IR) region revealed that the analyzed materials are appropriate for optoelectronic purposes. The thermoelectric behavior was examined as to figure of merit (ZT), electrical-conductivity (EC), the Seebeck-coefficient (S) as well as thermal-conductivity. Animatedly in future, the analyzed consequences would be supportive to experimental investigation of Rb2KScI6and Cs2KScI6for renewable energy device applications.

Optoelectronic devices designed with double perovskites are potentially emerging nowadays because of their interesting properties, such as simple and stable crystal structure. Our study theoretically explored the optoelectronic, mechanical, and thermoelectric characteristics of Rb2ScTlX6(X = Cl, Br, I) based on the density functional theory of the Wein2k code. The thermodynamic and structural stability is determined based on the enthalpy of formation and tolerance factor. The character of the compositions has been checked that either they are ductile or brittle by the elastic constants which are used to measure Passion and Pugh's ratio. For the elaboration of band gaps, Tran-Blaha mBJ potential is used, and the measured values of energy bandgaps are 3.5, 3.0, and 2.4 eV for Rb2ScTlCl6, Rb2ScTlBr6,and Rb2ScTlI6, respectively, using TB-mBJ plus spin-orbital coupling (SOC). These compositions are potentially used in solar cell devices like heterojunction solar cells because their electronic characteristics are controllable. In the energy range 0–12 eV, the compositions under consideration exhibit a single-peaked response, while the replacement of anions from Cl to I caused a shift in optical structures towards lower energies. The significant value of the figure of merits 0.77–0.95 makes them suitable for thermoelectric device applications.

The primary basis of renewable energy is transformation of light energy in the form of electrical energy that highly analyzed in past decade. By using Quantum espresso codethat based density functional theory, we have elucidated mechanical, electronic and optical properties of organic (CH3NH3)2AgMBr6(M = Sb, Bi) halides. In order to treat exchange-correlation functional, we employed PBE generalized gradient approximations (GGA) to execute the mechanical and opto-electronic parameters. Our calculated results of Pugh's ratio and Poisson's ratio of both halides recommended the quality of ductility. In addition, calculations regarding electronic and optical properties are obtained by using GGA + U in-order-to deliberating the accurate band gap. The required indirect band gaps for opto-electronic applications are calculated as 0.1 eV/0.88 eV for (CH3NH3)2AgSb/BiCl6.Interestingly, significant absorption coefficients for both halides endorse that these are appropriate opto-electronic devices in near-visible and infra-red regions.

In this work, we examine the half-metallic nature, optical and transport properties of ternary manganese selenides XMnSe2(X = Ca, Sr and Ba) by means of the ab-initio calculations. Hexagonal structures of these selenides have been explored using generalized gradient approximation (GGA) and predicted ground states parameters exhibits good agreement with experimental data. Half-metallic nature of studied ternary manganese selenides is confirmed by investigating band structure with spin polarized density of states (DOS). In addition, half-metallic nature has been investigated in terms of integer values of the magnetic moment. Materials response toward electromagnetic radiation of energy 0−60 eV is calculated in terms of dielectric constant. Minimum loss of energy and maximum absorption of electromagnetic radiation at low energy region make these materials applicable to Infra-red (IR) devices. Transport properties are also calculated by using BoltzTraP code at temperature 0–800 K. Our computed results of half-metallic nature and transport properties have been suggested that studied ternary manganese selenides play vital role in the field of spintronic and energy devices.

By using WIEN2k code, we investigated the mechanical and thermoelectric properties of magnesium based MgX2O4(X = Rh and Bi) spinels. To compute the mechanical behavior of MgX2O4(X = Rh and Bi), the Perdew-Bruke-Ernzerhof (PBEsol) flavor of generalized gradient approximation is used. From structural optimization, ground state lattice constant (a0) show a comparable with the previously evaluated theoretical and experimental values. The Born stability criterion represents that the investigated spinels are stable in the cubic phase and their ductile behaviors are observed by calculating Pugh’s ratio as well as Poisson ratio. Besides, thermodynamic behavior is concluded in terms of the Debye temperature. To investigate the electronic and thermoelectric behavior, the modified Becke and Johnson (mBJ) potential is employed. Finally, we investigated the thermoelectric behavior to represent the importance of studied spinels in thermoelectric appliances by calculating the figure of merit (ZT). High values of the See-beck coefficient and ZT at room temperature explores the potential of the studied spinels in thermoelectric devices.

Based on the ab-initio calculations, we have investigated the electronic, optical, and thermal properties of pristine SnSe and doped with oxygen (O) and sulphur (S) at the Se-site at concentration of 3.125%. The calculated negative formation energy indicates the stability of the pristine SnSe and doped system. We find that pristine SnSe possesses a direct bandgap value of 0.90 eV having good comparable to experimental value. The doping of O and S tunes the bandgap of SnSe, which can be promising for photovoltaic devices. Further, for the technological applications of O-/S-doped SnSe, we have analyzed optical properties in terms of absorption of photon energy and polarization. Strong absorption peaks confirms the direct transition of electrons from valence band to conduction band. Moreover, the thermal properties are calculated in terms of electrical/thermal conductivities, Seebeck coefficient, and figure of merit (ZT). At room temperature the ZT values are calculated round about 0.41 for O- and S-doped SnSe, respectively. We expect that our calculated thermoelectric parameters of the O- and S-doped SnSe could pave a new route for the application in the thermoelectric devices.

A fascinating novelclass of double perovskites materials with interesting optoelectronic and transport features have been discovered. In the current study, optoelectronics and the transport properties of Rb2LiTlX6(X = Cl, Br) were comprehensively examined. Structure stability was confirmed by calculatingtolerance factor value and Born stability criteria. At the Γ-symmetry point, direct band gaps of 2.90 eV and 1.66 eV are observed, ensuring spectral response throughout ultra-violet to visible areas and used as potential candidates for solar cell applications. These are excellent compounds for optoelectronic applications because of their low scattering of light, refractive index range approximately from 1.5 to 2, and wide absorption band in visible areas. Furthermore, thermal properties with the name electrical conductivity, thermal conductivity, Seebeck coefficient, power factor, and figure of merits of double perovskiteswere studied. The figure of merits (ZT) values of both compounds are 0.43, and 0.51 at room temperature, which confirms that these materials are suitable for use in thermal devices.

Double perovskite halides are probable renewable energy generation materials that are believed to fulfill the requirements for solving energy scarcity problems. Therefore, investigations of these hallides have emerging applications in the field of optoelectronic and thermoelectric devices. In current work, we also explored the physical characteristics of A2ScInI6(A=Rb, Cs) double perovskite halides in terms of DFT calculations based all electrons FP-LAPW+lo method for the applications renewable energy devices. The computed enthalpy of formation and goldsmith's tolerance factor shows that studied halides thermodynamically and structurally stable in cubic phase. Further, the investigated values of the Pugh and Poison ratios show a ductile nature by examining the elastic properties. Furthermore, we calculate bandgaps with and without spin-orbit coupling (SOC) by examining electronic properties. To obtain corrected bandgap values with respect to experimental values, we used modified Becke-Johnson (mBJ+SOC) potentials to calculate the bandgap values of Rb2ScInI6(Eg = 0.90 eV) and Cs2ScInI6(Eg = 0.95 eV). Also the optical properties of the studied halides are examined with regard to complex dielectric functions. Our calculated results of the optical parameters clearly indicate the optimal absorption of light in infrared (IR) areas, which represents the capability of these halides for being utilized in optoelectronic devices. The transport characteristics were examined in terms of figure of merit, electrical conductivity, thermal conductivity and Seebeck coefficient. Excitedly our results would be helpful for future experimental investigations to evaluate A2ScInI6(A=Rb, Cs) for applications related to renewable energy devices.