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Perovskite halides, owing to their environmental stability, non‐toxicity, and remarkable efficiency, are emerging as potential candidates for photovoltaic, solar cell, and thermodynamic applications. The electronic, optical, thermoelectric, and thermodynamic properties of cubic perovskite RbTmCl3 are studied using density functional theory (DFT). The electronic, optical, and thermoelectric properties are calculated both with and without spin‐orbit coupling (SOC) using the Tran and Blaha functional in the structure of the modified Becke Johnson (mBJ) exchange potential, while structural and mechanical properties are assessed using the exchange‐correlation functional calculated using the Perdew Burke Ernzerhof Generalized Gradient Approximation (PBE‐GGA). The negative formation energy (−592.39 KJ mol−1) and tolerance factor (1.17) for structural stability and current their existences in the cubic phase are found. Evaluation of the obtained data with and without SOC shows that the SOC effect causes the Tm‐d states to be shifted toward the level of Fermi, thereby decreasing the energy band gaps from 1.42 to 1.32 eV. Nevertheless, only the shift of the third variable peak to lower energies indicates the impact of SOC on optical properties. The effectiveness of RbTmCl3 in optical devices operating in the visible and ultraviolet regions is demonstrated by the exceptional absorption of light in these ranges. Using TB‐mBJ + SOC functional, the electronic band structure research reveals a direct semiconducting band gap of 1.32 eV in comparison to earlier calculations like LDA, PBE‐GGA, and TB‐mBJ. The absorption spectrum, reflectivity, extinction coefficient, refractive index, and dielectric function are displayed in addition to the electrical properties. Additionally, the quasi‐harmonic Debye model, which accounts for lattice vibrations, was used to study the corresponding volume, heat capacity, expansion of the heat coefficient, and Debye temperature of the RbTmCl3 crystal. We have calculated the thermoelectric parameters such as the Seebeck coefficient, thermal conductivity, electrical conductivity, and power factor as a function of temperature (100–900 K). [ABSTRACT FROM AUTHOR]

Herein, structural, electronic, and optical characteristics of pristine Sb2O3 and doped Sb2−xMxO3 (M = Cu, Ni, Zn; x = 0.25) for optoelectronic and allied applications are computed using Tran–Blaha modified Becke–Johnson (TB‐mBJ) approximation along with Hubbard correction. The calculated negative ground‐state energy values and absence of imaginary frequency at Gamma (Γ)point predict the dynamical and structural stability of all studied composites. The spin‐polarized electronic band structure, density of states (DOS), and 3D iso‐surface charge density analysis show reduced energy bandgap values for Sb2−xMxO3 with dopant at site B. In addition, Sb2−xNixO3 is found with minimal energy bandgap along spin‐down configuration. As regards optical response of composites, Sb2−xNixO3 offers maximum electromagnetic absorption in UV region and highest optical conductivity. Henceforth, Sb2−xNixO3 is found as most promising candidate among all studied composites for optoelectronic and allied applications. [ABSTRACT FROM AUTHOR]

Double perovskite is a potentially useful material for producing green energy and is thought to meet the necessary criteria for addressing energy shortages. That is why studies into these oxides have potential uses in the fields of optoelectronic technologies. In our present work, we have explored the structural, electronic, and optical properties of the double perovskites Sr2XWO6 (X = Co, Zn) using a first-principle study. Band structure and total density of state analysis shows that Sr2ZnWO6 has wider direct energy gap of 2.75 eV for both spin up and spin down configuration. While, Sr2CoWO6 has slightly reduced indirect energy band gap of 2.06 eV for spin up (↑) and 0.71 eV for spin down (↓) configuration. The dielectric function, absorption coefficients, reflectivity, and refractive index are used to analyze optical characteristics. The optical properties reveal that Sr2CoWO6 has shown much larger optical conductivity and electromagnetic radiation absorption in the UV and visible regions and a minimum value of reflectivity and energy loss function, which make it a suitable compound for optoelectronic applications. Our findings can be beneficial for further experimental research aimed at assessing Sr2XWO6 (X = Co, Zn) in spintronics, solar cell and optoelectronic device applications. [ABSTRACT FROM AUTHOR]

The structural, elastic, charge conduction and photoresponsive properties of halide perovskites, i.e., CsBX3 (B = Pb, Sn; X = I, Br, Cl) are investigated using the full potential‐linearized augmented plane wave (FP‐LAPW) method in the frame work of density functional theory (DFT). Perdew Burke Ernzerhof (PBE) functional belonging to the generalized‐gradient approximation (GGA) is implemented. For the better estimation of electronic parameters, the Tran–Blaha modified Becke–Johnson (TB‐mBJ) potential is employed. The elastic parameters such as bulk modulus, shear modulus, Young's modulus, the Pugh's ratio, anisotropy factor, Poisson's coefficient, and melting temperature (Tm) are estimated within Voigt‐Ruess‐Hill approximations. The energy band structure results, total density of states (TDOS), partial density of states (PDOS) outcomes, and isosurface charge density contour plots disclose that Sn2+and I1− are more appropriate divalent cation and anion respectively, among all studied composites especially for the application of photoresponsive resistive random access memory (RRAM) devices. Moreover, partial density of states (PDOS) outcomes depict that conduction band formation is consequence of hybridization of electrons from p‐orbitals of divalent cations, i.e., Pb, Sn and I/Br/Cl halogen anions. Besides, regarding charge conduction Sn‐based composites offer minimal energy bandgap as compared to Pb‐based composites. The energy bandgap order for Sn‐based compounds is found as CsSnI3> CsSnBr3> CsSnCl3. The optical analysis renders that CsSnI3 have the capability to absorb a wide range of ultraviolet (UV), visible and infrared (IR) electromagnetic incident radiations thus, make it much suitable material for optoelectronic memristors and associated applications. [ABSTRACT FROM AUTHOR]

The aim of this study is to figure out better metal dopants for CeO2 for designing highly efficient non-volatile memory (NVM) devices. The present DFT work involves four different metals doped interstitially and substitutionally in CeO2 thin films. First principle calculations involve electron density of states (DOS) and partial density of states (PDOS), and isosurface charge densities are carried out within the plane-wave density functional theory using GGA and GGA + U approach by employing the Vienna ab initio simulation package VASP. Isosurface charge density plots confirmed that interstitial doping of Zr and Ti metals truly assists in generating conduction filaments (CFs), while substitutional doping of these metals cannot do so. Substitutional doping of W may contribute in generating CFs in CeO2 directly, but its interstitial doping improves conductivity of CeO2. However, Ni-dopant is capable of directly generating CFs both as substitutional and interstitial dopants in ceria. Such a capability of Ni appears acting as top electrode in Ni/CeO2/Pt memory devices, but its RS behavior is not so good. On inserting Zr layer to make Ni/Zr:CeO2/Pt memory stacks, Ni does not contribute in RS characteristics, but Zr plays a vital role in forming CFs by creating oxygen vacancies and forming ZrO2 interfacial layer. Therefore, Zr-doped devices exhibit high-resistance ratio of ~ 104 and good endurance as compared to undoped devices suitable for RRAM applications. [ABSTRACT FROM AUTHOR]

The structural, optoelectronic, mechanical and thermoelectric features of Na2PtX6 (X = Cl and Br) for renewable energy applications are inspected by means of density functional theory DFT based calculations. Structural and thermodynamic stabilities are guaranteed by the Birch-Murnaghan equations of states, cohesive energy, and formation energy. The examined compounds are ductile, as indicated by the structural parameters and elastic constant analysis. For Na2PtCl6 and Na2PtBr6, the calculated direct band gaps of 3.20 eV and 2.24 eV ensure that light is absorbed in the visible and ultraviolet wavelength ranges. As a result, these materials are widely employed in solar cell and optoelectronic applications. The Boltztrap code is employed, which is based on the semi-classical Boltzmann transport equations (BTE), in order to investigate the thermoelectric properties. We have computed the electrical and thermal conductivities, Seebeck coefficient, power factor, and figure of merit (ZT) against temperature, carrier concentration, and chemical potential. According to the current study, Na2PtX6 (X = Cl and Br) is the most promising thermoelectric material for use in thermo power generation devices at a wide temperature range in the future. [ABSTRACT FROM AUTHOR]

Ternary perovskites are believed to satisfy the requirements for resolving energy shortage concerns and have the potential to be valuable materials for renewable energy production. Therefore, studies on these perovskites can prove useful for optoelectronic and thermoelectric devices applications. In the current study, DFT calculations based on the FP-LAPW technique were employed to examine the physical characteristics of YXO3 (X = Ga, In) oxide perovskite for applications in energy-efficient devices. To gain a better understanding of both materials electronic characteristics, the density of states (DOS) for each is also investigated. The bandgaps (Eg) of YGaO3 and YInO3 were found to be 3.82 and 2.33 eV, using the Trans Blaha modified Beck Johnson potential (TB-mBJ) potential. The determined formation energy and cohesive energy show that the investigated perovskites are both structurally stable in the cubic phase. Examining optical characteristics clearly shows that UV regions absorb incident light the best, indicating that the oxides under study have potential use in UV-based optical sensors and other optoelectronic devices. Investigating these materials thermoelectric characteristics is a practical way to use Boltztrap code, which is based on Boltzmann’s theory. The Seebeck coefficient at room temperature for YGaO3 is 263µV/K, whereas for YInO3, it is 207µV/K, according to the evaluation of the thermal transport parameters. Ultimately, the semiconductor properties of these materials, along with their effective thermoelectric coefficients, indicate that they are likely to be used in the development of thermoelectric gadgets and optoelectronic devices in the near future. [ABSTRACT FROM AUTHOR]

The present study unveils physical characteristics, including elastic parameters, phonon dispersion, electronics, optical, and thermoelectrics behavior's novel double perovskite Cs 2 CeAgX 6 (X = Cl, Br) by performing FP-LAPW computational approach. The mechanical stability of studied compounds has been addressed rigorously, and both compounds are ductile, revealing their potential for the fabrication of optoelectronic and thermal devices. Moreover, the phonon dispersion advocated about dynamical stability of the Cs 2 CeAgX 6 (X = Cl, Br) compounds. Both studied compounds have shown a wider band gap, a clear signature of a semiconductor nature. Spin-polarized electronic band structure's outcomes as well as electronic density of states have been computed using TB-mBJ approximation. Moreover, Cs 2 CeAgBr 6 offers a reduced gap rather then Cs 2 CeAgCl 6. The photo response analysis shows that Cs 2 CeAgBr 6 can absorb various ultraviolet (UV) and visible electromagnetic radiations. Henceforth, Cs 2 CeAgBr 6 is found to be a more suitable aspirant for optoelectronic device fabrication. Regarding composites' thermoelectric behaviour, the Seebeck coefficient reflects that studied materials are hole-based semiconductors computed by the BoltzTrap code. Cs 2 CeAgCl 6 has shown a higher thermal conductivity magnitude than Cs 2 CeAgBr 6 , so It's a potential thermoelectric material devices and allied applications. [ABSTRACT FROM AUTHOR]

Hybrid lead halide perovskites have been considered as promising candidates for a large variety of optoelectronic applications. By exploring novel combinations of lead-free double perovskite halides, it is possible to find a suitable replacement for poisonous lead halide perovskites, enhancing electronic and optical response for their application as optically-influenced resistive switching random access memory (RRAM). In this work, the structural, mechanical, elastic, electronic, optical, and thermoelectric characteristics of lead-free double halide perovskites were investigated by Vienna ab initio simulation package (VASP) to explore their role in RRAM. From the analysis of mechanical constraints, it is clear that all three composites of Cs 2 CaSnX 6 (X = Cl, Br, I) are mechanically stable and ductile in nature. The electronic bandgap with and without spin-orbit coupling (SOC), and total and sub-total density of states (TDOS, sub-TDOS) have been calculated using the Perdew-Burke-Ernzerhof generalized gradient approximation (PBE-GGA) potentials. The observed direct band gaps of 3.58 eV, 3.09 eV, and 2.60 eV for Cs 2 CaSnCl 6 , Cs 2 CaSnBr 6 , and Cs 2 CaSnI 6 , respectively, reveal the suitability of these specified composites as resistive switching material for RRAM devices. Additionally, the optical characteristics, such as complex refractive index, absorption coefficient, and reflectivity of the compounds under consideration have been calculated under the action of incident photons of 0 to 14 eV energy. The thermoelectric properties of Cs 2 CaSnX 6 (X = Cl, Br, I) double perovskite halide were computed and analyzed with the help of the BoltzTraP Code., Competing Interests: The authors declare that there are no conflicts of interest., (This journal is © The Royal Society of Chemistry.)

Atomic Layer Deposition (ALD) was used for a tri-layer structure (HfO 2 /Al 2 O 3 /HfO 2 ) at low temperature over an Indium Tin Oxide (ITO) transparent electrode. First, the microstructure of the fabricated TaN/HfO 2 /Al 2 O 3 /HfO 2 /ITO RRAM device was examined by the cross-sectional High-Resolution Transmission Electron Microscopy (HRTEM). Then, Energy Dispersive X-ray Spectroscopy (EDS) was performed to probe compositional mapping. The bipolar resistive switching mode of the device was confirmed through SET/RESET characteristic plots for 100 cycles as a function of applied biasing voltage. An endurance test was performed for 100 DC switching cycles @0.2 V wherein; data retention was found up to 10 4 s. Moreover, for better insight into the charge conduction mechanism in tri-layer HfO 2 /Al 2 O 3 /HfO 2 , based on oxygen vacancies (V OX ), total density of states (TDOS), partial density of states (PDOS) and isosurface three-dimensional charge density analysis was performed using WEIN2k and VASP simulation packages under Perdew-Burke-Ernzerhof _Generalized Gradient approximation (PBE-GGA). The experimental and theoretical outcomes can help in finding proper stacking of the active resistive switching (RS) layer for resistive random-access memory (RRAM) applications., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)