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Enhancing the rate performance of lithium-ion batteries (LIBs) is crucial to developing electronic devices. In light of the growing demand for consumer electronics, researchers have developed two-dimensional (2D) materials to achieve elevated performance levels. In this study, we applied the density functional theory (DFT) approach to assess the suitability of the novel 2D triphosphide AsP3 as a potential anode candidate for LIBs. The AsP3 monolayer exhibits high cohesive energy, outstanding structural stability, and impressive electronic properties. Our finding demonstrates that the valley site As2 is the optimal adsorption site for the Li atom on the AsP3 monolayer, with a high negative adsorption energy of -2.42 eV and considerable charge transfer. Moreover, the transition in behavior from semiconductor to metallic after the adsorption of Li on the substrate makes the AsP3 appropriate as an anode material of LIBs. Meanwhile, the AsP3 monolayer features a high theoretical storage capacity of around 638.71 mAhg− 1, exceeding that of commercial graphite and numerous other 2D materials. The diffusion barrier energy of the Li atom on the AsP3 monolayer is 0.29 eV, which is quite lower than that of many other 2D materials. This indicates rapid charge and discharge processes and underscores the high performance of the AsP3 monolayer. All these results demonstrate that the AsP3 monolayer could be a promising candidate for anode material in LIBs, paving the way for feature experimental studies in the development of battery technology. [ABSTRACT FROM AUTHOR]

Undoped and tin doped manganese oxide, Mn3-xSnxO4, (x=0, 2, and 4 at %) thin films were successfully elaborated by the chemical route defined in the spray pyrolysis technique and deposited on glass substrates at a temperature of 350 °C. The physicochemical characterization of the thin films was performed using an X-ray diffractometer (XRD) that showed a polycrystalline tetragonal structure for all thin films. Raman measurement confirmed the vibrational mode, A1g, and the XRD results with the presence of no secondary phases. Scanning electron microscopy coupled with energy dispersive X-ray spectroscopy depicted the surface morphology and the elemental composition (Mn, O, and Sn) of the elaborated thin films. Finally, the optical analysis was carried out, and it showed an increase in the average transmittance of the Mn3O4: Sn (0, 2, and 4 at %) from 57.6 % to 62.2 % for 700 nm and an increase of their optical band gap from 3.27 eV to 3.61 eV. We note also a decrease of their dispersive energy parameter Ed from 5.44 eV to 4.86 eV, of their static refractive index n0 from 2.02 to 1.86, as well as for their nonlinear optical parameters presented by the nonlinear refractive index n2 from 1.14 10-11 to 0.51 10-11 and the third order susceptibility χ3 from 6.14 10-13 esu to 2.49 10-13 esu. These values can be correlated to the poor crystallinity and the tensile strain of the Mn3O4: Sn (0, 2, and 4 at %) thin films, as well as to the high order of the optical bandgap energy and the decrease of the linear refractive index of these films. Hence, these thin films can be used as material for nonlinear optical applications.

We focus on the electronic, magnetic, and ferroelectric properties of the bilayer composite, Bi0.9La0.1Fe0.9Mn0.1O3/La0.8Sr0.2MnO3 (BFO-LM/LSMO). The studied films were processed on a Pt-substrate using chemical solution deposition. The morphology and structure purity of the synthesized films were characterized by field-emission scanning electron microscopy (FE-SEM) and x-ray diffraction (XRD). In addition, the simultaneous presence of macroscopic polarization and a fairly high magnetization were highlighted for the investigated specimen. In addition, the stability and electronic and magnetic properties of the BFO-LM/LSMO bilayer films with different stacking patterns have been explored using first-principles calculations. Moreover, the interfacial separation work for the Fe and Mn atoms at the interface in the BFO-LM/LSMO bilayer are 0.2069 J/m2 and 1.0309 J/m2, respectively, indicating that these systems have high stability, which is due to the strong hybridizations of the Fe_d, Mn_d, and O_p states at the interface. The interactions between the Fe and Mn spins at the interface lead to enhancing the remnant and saturation magnetizations in this system. The obtained results make BFO-LM/LSMO films a promising material for advanced spintronics and multifunctional devices. [ABSTRACT FROM AUTHOR]

In this study, undoped and cobalt‐doped manganese oxide Co:Mn3O4 (0, 2, and 4 at%) are elaborated by the spray pyrolysis procedure on glass substrates. The effect of cobalt doping concentrations on the structural, morphological, and optical features (linear and nonlinear) are investigated through the X‐ray diffractometer, Raman spectroscopy, Scanning Electron Microscopy with an attached energy dispersive X‐ray and UV–Vis‐NIR spectrophotometer. The XRD investigations exhibit a polycrystalline tetragonal structure for all Co:Mn3O4 and confirm by Raman results with the distinctive tetragonal mode A1g at 657 cm−1. The SEM images show an increase in roughness as cobalt doping concentration increases. The EDS quantitative analysis revealed the presence of manganese, oxygen, and cobalt. Furthermore, the optical investigation is pursued firstly through the linear optical that showed a decrease in the transmittance, and optical band gap energy as the cobalt concentration increased due to oxygen vacancies and defects and the increase of refractive index from 2.05 to 2.21. Second, the nonlinear optical parameters show a high value of the nonlinear refractive index 3.75 × 10−7 (esu) and the third‐order susceptibility χ3 = 2.2 × 10−8(esu) of Co:Mn3O4(2at%). These values put the Co:Mn3O4(2at%) thin layer as a candidate in the optoelectronic applications as a third‐order nonlinear medium. [ABSTRACT FROM AUTHOR]

We explored the mechanical, elastic, electronic, and optical properties of the thallium-based perovskite of TlGeX3 (X = F, Cl) using first-principles calculations within the framework of density functional theory under various hydrostatic pressures up to 25 GPa. The thermodynamic and mechanical stability of these perovskites was investigated using the formation energy and elastic constants, and the results show that the perovskites are stables and ductiles. Furthermore, the band calculations show that all perovskites are semiconductors with a band gap of 1.66 and 0.81 eV for TlGeF3 and TGeCl3, respectively, at 0 GPa. In addition, we explored the essential optical properties of the cubic perovskites TlGeX3 (X = F, Cl) in detail under different hydrostatic pressure values from 0 to 25 GPa, including optical absorption, reflectivity, refractive index, and imaginary and real parts of dielectric functions. The calculations show that the Bulk modulus B, Shear modulus G, Young’s modulus E and the elastic constants (C11 and C12) increase with the pressure, indicating that applying hydrostatic pressure improves the hardness of perovskites TlGeX3 (X = F, Cl). Our findings imply that these perovskites show high absorption and transition in nature from semiconductor-to-metal in the perovskites TlGeF3 and TlGeCl3, making them as a promising candidates for solar cells, ultraviolet absorbers, and optoelectronic device applications. [ABSTRACT FROM AUTHOR]

In this work, the structural, electronic, magnetic, and electrical properties of tri-layered SrMO3/BaTiO3/SrMO3 (M = Ru and Os) have been investigated using first-principles calculations based on density functional theory in the framework of GGA + U. The interfacial separation work indicates that the studied tri-layers are energetically stable. Moreover, the simultaneous presence of spontaneous polarization and magnetization with matallic characteristics was predicted. In addition, the electrical and thermal conductivities as a function of temperature are obtained using the semi-classical Boltzmann transport theory. The obtained results make the studied systems promising materials for spintronic applications. [ABSTRACT FROM AUTHOR]

In this paper, the first‐principles calculations based on the Density Functional Theory (DFT) have been used to study the effect of strain on the structural, electronic, optical and thermoelectric properties of the puckered Si2SeS monolayer. Our calculations show that the puckered Si2SeS monolayer has an indirect band gap of 1.30 eV at the equilibrium state, which can be tuned by biaxial strain and the semiconductor–metal phase transition occurs at −10%. Interestingly, a high absorption coefficient exceeds 107 cm−1 in the visible light region under compression biaxial strain was predicted. The electronic Figure of merit (ZTe) of puckered Si2SeS monolayer reaches 2.55 under the tensile biaxial strain of +6%. The presented results show the promising potential of puckered Si2SeS monolayer for optoelectronic and energy conversion applications. [ABSTRACT FROM AUTHOR]

Two-dimensional materials offer the potential to attain nanoscale optoelectronic and thermoelectric devices. In this paper, the electronic structure and thermoelectric potential of β-Sb/GeI2 van der Waals (vdW) heterostructures with two different stacking configurations (AA and BA) were investigated using first-principles calculations in the framework of density functional theory combined with the semi-classical Boltzmann theory. Band gaps of 1.25 and 2.18 were extracted from the band structures for the β-Sb and GeI2 monolayers, respectively. For the AA and BA stacking of the β-Sb/GeI2 heterostructure, band gaps of 0.86 and 0.75 eV were calculated, respectively. We also analyzed the effect of temperature and chemical potential on transport properties. Interestingly, high electronic figure of merit ZTe values of 6.61 (at 0.067 Ry) and 44.40 (at - 0.037 Ry) were achieved for AA and BA stacking at room temperature, respectively. Moreover, the ZTe increased sharply, showing a giant value of 17.69 (at 380 K) for AA stacking. However, for BA stacking a decreased value of 26.67 (at 420 K) was achieved, which was attributed to the Seebeck coefficient value, indicating very good potential for β-Sb/GeI2 heterostructures in energy harvesting and solid-state cooling applications. [ABSTRACT FROM AUTHOR]

The so-called antimonide materials of XSb2 type have attracted considerable attention owing to their excellent properties. In this paper, first-principles calculations are used to study the electronic structure and optical properties of iron antimonide FeSb2. The electronic calculations have shown that the FeSb2 compound has a metallic character. Moreover, the optical properties like the real part ε1(ω) and imaginary part ε 2(ω) of the dielectric constant, refractive index n(ω), reflectivity R(ω), extinction coefficient k(ω), absorption coefficient α(ω), and optical conductivity σ(ω) versus the energy are determined. Interestingly, it is found that FeSb2 revealed an excellent reflection, indicating that the predicted tetragonal structure of FeSb2 is a promising candidate for optical applications such as mirrors and coatings on glasses in infrared region. [ABSTRACT FROM AUTHOR]

The Janus two-dimensional (2D) materials have recently demonstrated excellent physical and chemical properties. The electronic, thermoelectric, and optical properties of the Janus In2SeTe monolayer have been investigated using density functional theory (DFT) calculations. Our results revealed the Janus In2SeTe monolayer has a direct bandgap of 1.07 eV, which is desirable and smaller than that of InSe and InTe. The studied optical properties indicate that Janus In2SeTe monolayer has a very good absorbing capability of light from the infrared region to ultraviolet one with a large absorption coefficient. Moreover, the thermoelectric property calculations suggest that the In2SeTe Janus monolayer can be a potential thermoelectric material, with a great electronic figure of merit ( ZT e ) of 0.97 at 300 K. In addition, the ZT e increases with temperature up to a value of 1.42 at 800 K. Our results revealed the Janus In2SeTe monolayer possesses good properties that could offer the possibility of optoelectronic and energy conversion applications. [ABSTRACT FROM AUTHOR]