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The exceptional optical and electrical properties of Single-Walled Carbon Nanotube (SWCNT) material present significant potential for solar cells, especially when used with zinc oxide (ZnO) as a buffer layer. This study examines the electrical characteristics and performance metrics of ZnO/SWCNT solar cells using the SCAPS-1D software. Understanding the impact of various factors such as temperature, thickness, and operational resistors (Rs and Rsh) on the performance of this photovoltaic device is crucial. The ZnO/SWCNT solar cell demonstrates impressive power conversion efficiency (η = 24.42 %), an open-circuit voltage (Voc) of 0.7740 V, a short-circuit current density (Jsc) of 40.303777 mA/cm2, and a fill factor (FF) of 78.27 %. These parameters can be further enhanced through optimization, resulting in an efficiency of η = 26.44 %. Therefore, the results of this simulation suggest the potential for highly efficient solar cells and significant future technological advancements.

Organic-inorganic hybrid perovskites have emerged as promising materials for photovoltaic applications. This study investigates the impact of chlorine (Cl) doping on the electronic and optical properties of the perovskite CH3NH3SnI3 (MA-SnI3) using density functional theory (DFT) calculations. We explore Cl doping concentrations of 8.33%, 16.66%, and 25%, analyzing the resulting changes in bandgap, density of states, and absorption coefficient. DFT calculations reveal a significant reduction in the bandgap with increasing Cl concentration, shifting from 1.055 eV for the methylammonium tin iodide structure to 0.727 eV, 0.731 eV, and 0.792 eV for the doped structures, respectively. Analysis of the density of states highlights the influence of Cl on the electronic structure. Furthermore, the absorption coefficient increases within the visible range, suggesting enhanced light absorption capabilities. Our results are consistent with experimental observations, validating the accuracy of DFT as a tool for studying Cl-doped MA-SnI3 perovskites and providing insights into their potential for solar cell applications.

In this paper, we have calculated the structural, electronic, and optical properties of chalcogenide stannite Cu2CdSnX4 (X=S, Se, Te) materials. The calculations are based on the density functional theory (DFT) method and are performed using the Cambridge sequential total energy package (CASTEP) code included in the Biovia Material Studio 20 software. All optical properties have been studied in a domain that extends energetically from 10 meV to 40 eV. Our results show that Cu2CdSnX4 (X=S, Se, Te) stannite exhibits absorption in the visible region, the refractive index decreases with increasing energy, and the refractive index values are n=3.2, 3.73 and 3.75 for Cu2CdSnS4, Cu2CdSnSe4 and Cu2CdSnTe4, respectively. They show also high conductivity, which implies that this material is promising for solar cells. These results argue in favor of the use of these materials in various potential applications. The density of state, band structures, and structural properties of Cu2CdSnX4 (X=S, Se, and Te) stannite are also studied in this work. [ABSTRACT FROM AUTHOR]

The present research explores the structural characteristics of pure copper (Cu) metallic glass using the embedded atom method (EAM) potential in molecular dynamics simulations. Numerous techniques were used, such as coordination number analysis, Voronoi tessellation, and the radial distribution function (RDF). The findings demonstrate that at a cooling rate of 1012 K/s, crystallization begins. However, the separation of the second RDF peak indicates that under 0 GPa, copper metallic glass forms at cooling rates between 5 × 10¹² K/s and 1014 K/s, with the glass transition temperature (Tg) rising with faster cooling. Voronoi tessellation revealed a rise in icosahedral clusters with quicker cooling, while coordination number analysis indicated changes in the local structure and topology of copper metallic glass during the cooling process.

In recent years, double perovskite oxides have gained attention as promising candidates in the realms of solar cells and catalysis. By adjusting their composition and engineering the band gap, numerous materials are being developed for energy-related applications. Oxide perovskites offer the benefit of a longer carrier lifetime compared to halide perovskites, which is advantageous for energy applications. In this study, we present a systematic theoretical analysis of a double perovskite oxide, examining his composition. The associated electronic and optical properties are discussed, along with prospects for identifying highly efficient materials within this family. This paper reports the study of electronic and optical properties of double perovskite oxide LaFeWO6 by utilizing the FP − LAPW method within the framework of (DFT). Results of density of states and energy bands are presented. The direct band gaps have been found for the systems by using the GGA approximation. Calculations of optical properties is also presented by considering the variations of optical parameters as a function of incident photon energy. The results indicate that LaFeWO6 exhibits a suitable band gap (0.71eV) for visible light absorption, along with promising electronic properties, making it a candidate for photocatalytic and photovoltaic applications.

This study investigates the electronic and optical properties of calcium-doped strontium hydride (SrH2) using first-principles density functional theory (DFT) calculations via the CASTEP code with generalized gradient approximation (GGA). We explore the impact of calcium (Ca) doping on the electronic band structure, density of states (DOS), and optical absorption spectra of SrH2. Our results show that Ca doping significantly alters the electronic properties of SrH2, notably increasing the indirect bandgap from 1.3 eV to 1.6 eV. The DOS analysis reveals new states near the Fermi level, primarily from Ca 3d orbitals. Moreover, the optical absorption spectra display enhanced absorption in the visible range, suggesting the potential for optoelectronic applications. This research highlights the feasibility of tuning the electronic and optical characteristics of SrH2 through Ca doping, thus opening the way for the generation of advanced materials with tailored properties. [ABSTRACT FROM AUTHOR]

In this study, we utilized molecular dynamics simulations with the embedded-atom approach to explore how different cooling rates and concentrations of chromium (Cr) affect the vitrification of metallic glasses (MGs) composed of a binary alloy FexCr100-x. We assessed this impact by analyzing the glass transition temperature (Tg) and the activation enthalpy (Δh). The results reveal an interesting non-linear trend in the activation energy. Specifically, there is a sharp decrease observed at a chromium concentration of 50%, followed by a slight increase at the 75% concentration level. These kinetic observations are linked to microstructural data obtained through Voronoi polyhedral analysis (VPA). However, it's worth noting that the influence of varying cooling rates on the vitrification process appears to be relatively modest.

The development of important materials for photovoltaic applications is rapidly advancing, particularly in the field of perovskite materials. This study investigates the optical and electronic characteristics of CH 3 NH 3 Pb I3 and analyzes the influence of doping in perovskite CH 3 NH 3 Pb I3 with different concentrations of sodium ions Na+. In this study, we employed Density Functional Theory to assess the optical and electronic properties of both pure and Na+ ion-doped CH 3 NH 3 Pb I3, with Na+ concentrations of 12.5 %, 25 %, and 37.5 %. The bandgap energy of pure CH 3 NH 3 Pb I3 rises from 1.205 eV to 1.573 eV as the concentration of Na+ ions increases from 0 % to 37.5 %, respectively. Doping with Na+ ions leads to an increase in the absorption coefficient of pristine CH 3 NH 3 Pb I3 perovskite in both UV and visible ranges. Doping likewise affects the density of states, dielectric function, and the refractive index of CH 3 NH 3 Pb I3 material. These findings offer vital insights into modulating the electronic and optical characteristics of CH 3 NH 3 Pb I3 through Na+ ion doping.

In this groundbreaking study, we unveil the remarkable structural, electronic, and optical Properties of the newly discovered double perovskite material, K2AgBiI6, presenting a paradigm shift in materials science. The unique crystal structure and diverse atomic interactions inherent in this double perovskite make it an up-and-coming candidate for various technological applications, particularly in photovoltaics; owing to its stability and resistance to heat and humidity, we aim to shed light on the extraordinary potential of K2AgBiI6. Our study provides valuable insights for researchers engaged in tailored material design. We anticipate that the exceptional electronic properties of K2AgBiI6 will not only redefine the boundaries of materials engineering but also catalyze unprecedented advances in sustainable technology. Employing the powerful computational tool CASTEP, we conducted detailed electronic structure calculations within the framework of Density Functional Theory (DFT) to unravel the electronic properties of the double perovskite K2AgBiI6. Our investigation thoroughly explored structural properties, band structure, total density of states (DOS), and partial density of states (PDOS). Furthermore, we systematically examined the influence of different exchange-correlation functionals, including LDA, GGA, and m-GGA, on the electronic and optical features of the material by presenting a comparative analysis of these approximations. [ABSTRACT FROM AUTHOR]

In this study, a computational analysis based on density functional theory is conducted to study the elastic, mechanical, vibrational, and thermodynamic properties of novel chalcogens, Ag2BeSnX4 (X = S, Se, and Te). We used the generalized gradient approximation (GGA) within the framework of density functional theory (DFT). The mesh parameter values (a and c) were calculated using the X-ray diffraction method. The calculated elastic constants indicate that the bond strength along the [1 0 0] directions is stronger than that along the direction [0 0 1]; according to the Born-Huang stability criterion, we can see that they are mechanically stable. A high value of the ratio (B/G) is associated with ductility for Ag2BeSnX4 (X = S, Se, and Te) materials. Additionally, the Raman shifts of all samples are calculated. Between 10 and 1000 K in temperature, the vibrational mode shifts were calculated for three chalcoginides. The thermal behavior of these movements shows that these structures can undergo deformation with increasing temperature. These results suggest a first contribution to the understanding of the effect of temperature on the vibrational modes of three kesterite structures Ag2BeSnX4 (X = S, Se, and Te) and consequently on their structures. The heat capacity (C V) , free energy (F) , entropy (S) , and enthalpy (H) are also computed. The kesterite phase of the Ag2BeSnX4 (X = S, Se, and Te) structures aligns with theoretical findings in elastic properties, exhibiting superior elastic properties. These attributes are valuable for the design of optoelectronic devices. [ABSTRACT FROM AUTHOR]