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We investigate the comprehensive analysis's structural, electronic, optical, and elastic properties of Cs₂NaScX₆ (X = Cl, Br) double perovskites using density functional theory (DFT) implemented by the WIEN2k code. The results show that both compounds are in cubic phases. The calculated tolerance factors show both are stable compounds. The computed optimized lattice parameters are Cs₂NaScX₆ (X = Cl, Br) are 10.72 Å and 12.01 Å, respectively. Employing a modified Becke–Johnson (mBJ) potential electronic nature shows that both compounds are in semiconductor nature, that is, 3.138 eV and 3.977 eV. The calculated elastic constant and perimeters show the Cs₂NaScX₆ (X = Cl, Br) are mechanical stables and also ductile and anisotropic nature. The optical properties described the range of photon energies from 0 to 10 eV, revealing pronounced absorption within the visible spectrum, highlighting their considerable promise for transformative innovations in photovoltaic technology. These double perovskites exhibit superior absorption characteristics compared to their Cs₂NaScX₆ (X = Cl, Br) analogues, thus laying the groundwork for significant advancements in solar energy conversion and photovoltaic applications. [ABSTRACT FROM AUTHOR]

The novel molybdenum oxide iodide/poly-o-aminobenzenethiol (MoO2I2/POABT) nanocomposite thin film presents a promising solution for advanced light sensing and captures in optoelectronic devices. This thin film is fabricated through a two-step process: first, the oxidation of o-aminobenzenethiol using iodide, followed by a reaction with Na2MoO4, leading to the integration of MoO2I2 within the POABT matrix. The resulting film has a notable bandgap of 2.2 eV, a tube-shaped morphology with a diameter of 150 nm, and a crystalline size of 119 nm, making it ideal for use as a light sensor and optoelectronic device. Device sensitivity is evaluated using linear sweep voltammetry under light exposure. The photocurrent density (Jph) reaches 0.88 mA/cm², with a photocurrent of 0.28 mA/cm². Sensitivity testing across various photon energies and wavelengths shows peak Jph values at 340 nm and 440 nm, with strong performance at 540 nm and 730 nm. Noteworthy photoresponsivity (R) is observed at 340 nm and 440 nm, with values of 8.0 and 7.4 mA/W, respectively. Additional R values of 6.3 and 6.0 mA/W are noted at 540 and 730 nm. The highest detectivity (D) values are recorded at 340 nm and 440 nm, measuring 0.181 × 10¹⁰ and 0.167 × 10¹⁰ Jones, while lower D values of 0.142 × 10¹⁰ and 0.135 × 10¹⁰ Jones are seen at 540 nm and 730 nm, respectively. The MoO2I2/POABT nanocomposite thin film shows great potential for commercial and industrial optoelectronic applications with its excellent reproducibility, strong performance metrics, and simple and scalable fabrication process. [ABSTRACT FROM AUTHOR]

Dion–Jacobson‐type 2D halide perovskites (DJPs) present an ideal alternative to their 3D counterparts due to their superior stability and exceptional optoelectronic properties. Despite the numerous DJPs proposed in recent years, the impact of different spacer cations on DJPs remains unclear. This understanding is crucial for researchers to select suitable materials and is an urgent requirement for the development of higher‐performance DJPs‐based devices. In this study, the influence of the chain‐like spacer cations with varying branch chains and chain lengths is thoroughly examined using both theoretical and experimental methods. The findings reveal that spacer cations with high polarity components along the main chain direction enhance the stability and photoelectric properties of DJPs. Additionally, it is found that the chain length of the spacer cation plays a critical role. Chain lengths that are too long or too short can detrimentally affect the photoelectric performance and stability of DJPs. These insights will guide researchers in selecting suitable spacer cations and in innovating new types of DJPs. [ABSTRACT FROM AUTHOR]

Organic photovoltaic cells (OPVs) are a promising low‐cost renewable energy technology. Among various semiconductors studied for OPVs, boron subphthalocyanine chloride (Cl‐BsubPc) is one of the most explored. Phenoxy‐substituted BsubPc (PhO‐subPc) is an analogue of Cl‐BsubPc that introduces an axial phenoxy ligand in order to tune its electronic properties. In this paper, the effects of halogen substitution on the optoelectronic properties of PhO‐subPc are discussed in terms of the nature, number, and location of halogen atoms. DFT calculations show that the peripheral halogen substitutions significantly decrease the exciton binding energy value, increase the reorganization energy value, and also improve the light‐harvesting efficiency of the mentioned molecules. These modifications are symptoms of improved exciton separation and charge transport; hence, the peripherally halogenated PhO‐subPc are those that exhibit the best performances. However, the phenoxy‐substituted BsubPc do not enhance the performance of the boron subphthalocyanine chloride as far as the hole transport materials (HTM) of organic solar cells are concerned. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising clean energy source, but its storage poses challenges. In this research, we conducted an in-depth study of the structural and optoelectronic properties of the β- AlH 3 phase as a potential material for hydrogen storage. Using the density functional theory (DFT)-based Wien2k code, we optimized the structure of β- AlH 3. Hydrogen storage properties show that β- AlH 3 contains 10.1% hydrogen by weight, which is a significant amount. Electronic properties reveal that this material is a semiconductor with a wide indirect bandgap of 5.947 eV, obtained by the generalized gradient approximation with modified Becke-Johnson correction (GGA-mBJ). The optical response of β- AlH 3 to photons with energies from 0 to 10 eV is also examined for a better understanding of this material. β- AlH 3 exhibits a static dielectric permittivity value ε 1 (ω) of 2.1, indicative of its semiconducting nature. The optical conductivity σ 1 (ω) shows peaks at 7.25 eV and 8.5 eV, while the absorption coefficient α(ω) increases significantly above the band gap of 5.947 eV, with peaks at 7.2 eV and 9 eV. The refractive index n(ω) and extinction coefficient κ(ω) both display notable features at 7.2 eV and 9 eV, reflecting substantial electronic transitions and optical resonances. This research is crucial to understanding how this material can meet the technological demands of hydrogen storage. The results provide valuable insights into the potential of β-AlH₃ within the future energy landscape, highlighting both advances and challenges in this promising field. • Determination of crystal lattice parameters and structural stability of β-AlH₃. • Analysis of band gaps, density of states, and optoelectronic properties of β-AlH₃. • Evaluation of β-AlH₃'s hydrogen absorption mechanisms and energy storage efficiency. • Study of electron-photon interactions and plasmon resonances affecting optical properties. • Computational results support β-AlH₃'s potential in hydrogen storage technologies. [ABSTRACT FROM AUTHOR]

High frying quality in terms of frying colour is an important trait for potatoes meant for French fry production. Determination of frying colour is often performed visually, which might be affected by biases and is therefore less suitable for research. Available laboratory methods also lack the capability to cover the whole sample and distinguish between tuber parts. Additionally, sample destruction is often required for colour analysis. Therefore, a new approach using RGB colour values and the subsequent R/G ratio of French fries to assess frying colour was tested in this research. Over the course of 3 years, 673 samples of the cultivar Innovator were assessed and compared to visual scoring, and some samples were also assessed for glucose content. A high correlation of R2 = 0.8346 between the visual scoring and the optoelectronic assessment was found for 633 samples. The validation data set of 40 samples reached a correlation of R2 = 0.7850 with the implemented model. These results show that French fry frying colour can be described using the R/G ratio. This promising approach is suitable for other researchers as well as industry professionals with further research. [ABSTRACT FROM AUTHOR]

Density Functional Theory (DFT) is incorporated in this study to examine the thermodynamic, electronic, mechanical, and optical characteristics of antiperovskite compounds A3BO (A = K, Rb and B = Au, Br). The purpose of the study is to demonstrate a comprehensive understanding of these materials and their potential applications across various fields emphasizing their stability and energetic profiles. The electronic properties, including band structures, and density of states are also analyzed to understand the electrical behavior of these materials, which enables predicting their conductive and semiconductor nature. The band gaps of K3AuO, K3BrO, Rb3AuO, and Rb3BrO are 0.72 eV, 0.80 eV, 0.15 eV, and 0.29 eV, respectively. The study also investigated the mechanical properties of the antiperovskite structures, including elastic constants, bulk modulus, and shear modulus to provide insights into their mechanical stability and durability. Their Pugh's ratio (B/G) is below 1.75 and negative Cauchy pressure indicates these compounds are brittle. And machinability index B/C44 > 1.5 implies excellent lubricating properties. This phenomenon extends the potential industrial application of materials with specific mechanical integrity to their structural components. Additionally, the study investigated the optical properties of the A3BO antiperovskite compounds, including the dielectric function, loss function, reflectivity, conductivity, refractive index, and absorption spectra. These findings provide a comprehensive understanding of how these materials interact with light, which could be useful in the development of optoelectronic devices. Overall, this DFT study provides significant insights into the multifaceted properties of A3BO antiperovskite compounds, laying the groundwork for further experimental exploration and facilitating the targeted design of materials with tailored properties for specific technological applications. [ABSTRACT FROM AUTHOR]

Flexible polymer nanocomposite composed of organic methylcellulose (MC) and semiconducting titanium dioxide (TiO2) films were successfully prepared. The energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) recorded the structure characteristics of the films, proving that MC/TiO2 nanocomposite were successfully synthesized. The EDX showed that this composite was composed of (28.55% C, 50.90% O, and 20.55% Ti), which displayed the chemical composition of MC/TiO2. Moreover, the scanning electron microscope (SEM) shows the TiO2 nanoparticles are loaded homogenously in the nanocomposite films. With increasing the TiO2, the FTIR intensity of most peaks gradually decreased which may be attributed to that titanium dioxide nanoparticles (TiO2 NPs) were formed on the methylcellulose (MC). The UV spectrophotometer records the data of absorption (A) for the MC and MC/TiO2 films between 200nm and 1100nm at the ambient temperature. Using Tauc’s relation, the linear/nonlinear optical characteristics of MC and MC/TiO2 films were computed. By mixing MC with 2%, 4%, and 6% TiO2, the Urbach energy of the MC is enhanced from 1.77eV to 1.85, 2.02, and 2.34eV, correspondingly, while the TiO2 reduced the energy gap of MC from 5.17eV to 3.59, 3.52, or 3.43eV. Moreover, the carbon cluster increased from 44 for MC to 92, 95, and 101 for MC mixed by 2%, 4%, and 6% TiO2. This study found the MC/TiO2 hybrid films can potentially be used as optical materials for flexible electronic devices. [ABSTRACT FROM AUTHOR]

Scientists devote their time and energy to studying and developing hydrogen storage devices to address the energy crisis and climate change. Because of this, investigations are conducted to reveal the optoelectronic, structural, bader charge, electronic charge density, and hydrogen storage properties of X 2 LiAlH 6 (X = K, Mn) within the framework of density functional theory, and calculations of the structural characteristics were carried out utilizing local and nonlocal, and hybrid functionals. An additional onsite Coulomb parameter (GGA + U), which includes the Hubbard parameter, was used to apply the potential. Calculations based on the Kramer-Kroning principle were used to determine the dielectric function, refractive index, extinction coefficient, and energy loss function. The results indicate that K 2 LiAlH 6 and Mn 2 LiAlH 6 are highly suitable for hydrogen storage applications. The gravimetric ratios of hydrogen storage capacities for both investigated materials are 5.2 wt %, and 7.5 wt %, respectively. The interaction of the Mn-d, Li-s, K-s, and H-s/p orbitals was the cause of hybridization, according to the optoelectronic characteristics. Compound stability is indicated by the negative computed formation energy of the materials under investigation. The electronic charge density analysis showed a mixed-bond semiconductor with low ionicity and high covalence. In addition, the radiation shielding properties of Mn 2 LiAlH 6 and K 2 LiAlH 6 were investigated using Phy-X software, showing promising results in linear attenuation, half-value layer, and mean free path, particularly for Mn 2 LiAlH 6 due to its higher atomic number. This groundbreaking study represents a pioneering computational exploration of X 2 LiAlH 6 , offering promising advancements for future research in hydrogen storage applications. • The structural properties of X 2 LiAlH 6 were analyzed using DFT, revealing promising stability metrics. • Mn 2 LiAlH 6 shows enhanced radiation shielding due to its higher atomic number and interaction effects. • Hydrogen storage capacity for K 2 LiAlH 6 and Mn2LiAlH6 was calculated to be 5.2 wt % and 4.7 wt %, respectively. • Phy-X software simulations revealed Mn 2 LiAlH 6 's superior shielding performance against gamma rays. • Optical properties demonstrated high absorption coefficients, indicating potential for energy applications. [ABSTRACT FROM AUTHOR]

Pseudo-cubic perovskite La-doped SrSnO 3 has been proposed as a promising alternative for ultra-violet (UV) transparent conductors due to its favorable electrical transport properties and UV transparency. However, the difficulty in fabricating large-size La-doped SrSnO 3 films with high electrical mobility continues to hinder the development of practical applications. In this work, Sr 0.94 La 0.06 SnO 3 (SLSO) thin films with wide bandgap of ∼4.5 eV were fabricated by using solution deposition route. Emphasis was placed on creating oxygen-poor environments and selecting appropriate post-annealing temperatures, which were determined based on the kinetic energy of relevant defects and second-phase impurities. Post-annealing treatment was applied to refine the microstructure and enhance electrical transport properties. As a result, a relatively high carrier mobility of 25.9 cm2 V−1 s−1 and a low resistivity of 1.15 mΩ cm at a carrier concentration of 2.08 × 1020 cm−3 were achieved. Enhanced electrical properties were attributed to the increased presence of oxygen vacancies, as confirmed by electron paramagnetic resonance results. This study presents a straightforward approach for the production of large-scale epitaxial UV transparent conducting SLSO thin films. [ABSTRACT FROM AUTHOR]

This research explores the design of an infrared (IR) photodetector using mercury cadmium telluride (Hg1–xCdxTe). It proposes two- and three-dimensional homojunction models based on p+-Hg0.7783Cd0.2217Te/n–-Hg0.7783Cd0.2217Te, focusing on applications in the long-wavelength infrared range. The photodetector's performance is analyzed using Silvaco ATLAS TCAD software and compared with analytical calculations based on drift-diffusion, tunneling, and Chu's approximation techniques. Optimized for operation at 10.6 μm wavelength under liquid nitrogen temperature, the proposed photodetector demonstrates promising optoelectronic characteristics including the dark current density of 0.20 mA/cm2, photocurrent density of 4.98 A/cm2, and photocurrent density-to-dark current density ratio of 2.46 × 104, a 3-dB cut-off frequency of 104 GHz, a rise time of 0.8 ps, quantum efficiency of 58.30 %, peak photocurrent responsivity of 4.98 A/W, specific detectivity of 3.96 × 1011 cmHz1/2/W, and noise equivalent power of 2.52 × 10–16 W/Hz1/2 indicating its potential for low-noise, high-frequency and fast-switching applications. The study also incorporates machine learning regression models to validate simulation results and provide a predictive framework for performance optimization, evaluating these models using various statistical metrics. This comprehensive approach demonstrates the synergy between advanced materials science and computational techniques in developing next-generation optoelectronic devices. By combining theoretical modeling, simulation, and machine learning, the research highlights the potential to accelerate progress in IR detection technology and enhance device performance and efficiency. This multidisciplinary methodology could serve as a model for future studies in optoelectronics, illustrating how advanced materials and computational methods can be utilized to enhance device capabilities. [ABSTRACT FROM AUTHOR]

A polypyrrole-bismuth tungstate (Ppy-Bi2WO6) core-shell nanocomposite (n-type material) has been developed on a layered Ppy (p-type) base as an efficient light-capturing material exhibiting photodiode behavior. This device demonstrates promising sensitivity for light sensing and captures across a broad spectral range, from near IR to UV. The Bi2WO6/Ppy nanocomposite boasts an optimal bandgap of 2.0 eV, compared to 3.4 eV for Ppy and 2.5 eV for Bi2WO6. The crystalline size of the core-shell composite is approximately 21 nm, emphasizing its photon absorption capabilities. The composite particles, around 100 nm in length, feature a highly porous morphology that effectively traps incident photons. The performance of this optoelectronic device is evaluated using current density (J) measurements under light (Jph) and dark (Jo) conditions. In darkness, the n-p type semiconductor exhibits limited current with a Jo of −0.22 mA cm−2 at 2.0 V. When exposed to white light, the Ppy- Bi2WO6/Ppy device generates hot electrons, achieving a Jph value of 1.1 mA/cm−2 at 2.0 V. It shows a superior responsivity (R) of 6.6 mA/W at 340 nm, gradually decreasing to 6.3 mA/W at 440 nm and 4.2 mA/W at 540 nm, indicating high sensitivity across the UV-Vis spectrum. At 730 nm, the R-value is 2.6 mA/W, highlighting its sensitivity in the near IR region. Additionally, at 340 nm, the device achieves a detectivity (D) value of 0.15 × 10¹⁰ Jones, which decreases with longer wavelengths to 0.14 × 10¹⁰ Jones at 440 nm, 0.9 × 10⁹ Jones at 540 nm, and 0.63 × 10⁹ Jones at 730 nm. With its great stability, low cost, easy fabrication, and potential for mass production, this optoelectronic light sensor and photodiode device holds significant promise for industrial applications as a highly effective optoelectronic device. [ABSTRACT FROM AUTHOR]

This article comprehensively explores the structure, stability, mechanical, optoelectronic, and thermoelectric aspects of the emerging double perovskites A2YCuZ6 (A = Rb, Cs and Z = Cl, Br). The structural and mechanical characteristics are estimated using the PBE-GGA functional, whereas the optoelectronic and thermoelectric characteristics are computed using the modified Becke and Johnson potential. Tolerance factor, formation energies, and Gibbs free energies have validated the cubic phase and thermodynamic stability. The anticipated elastic values indicated that all the materials exhibited mechanical stability, ductility, and anisotropic behavior. The computed electronic features verified that Rb2YCuCl6, Rb2YCuBr6, Cs2YCuCl6, and Cs2YCuBr6 have indirect band gaps of 1.95, 1.30, 1.55, and 1.2 eV, respectively. This work also explores the optical response in the energy range 0 to 6 eV in terms of polarization, refractive index, absorption, and optical conduction. The visible and ultraviolet ranges of light are both significantly absorbed, making these materials optimal for use in solar systems. The BoltzTraP code has been used to calculate the transport parameters, demonstrating the p-type semiconductors nature of these materials. Further, the significant merit values of 0.77, 0.83, 0.82, and 0.81 at room temperature for analyzed materials suggest their potential applicability in thermoelectric devices. Hence, the investigated double perovskites, which are not empirically validated, have been recommended as extremely suitable alternatives for creating various energy conversion applications. [ABSTRACT FROM AUTHOR]

Ab-initio simulations using density functional theory (DFT) were employed to investigate the structural, mechanical, electronic, magnetic, optical, and thermoelectric properties of halide perovskites (X = Cl, Br, I). Structural optimization and mechanical stability assessments confirm the reliability of these perovskites in a hexagonal P mc symmetry. The stability of the ferromagnetic phase was validated through total crystal energy minimization via Murnaghan's equation of state. Electronic band structures and density of states, derived from the generalized gradient approximation (GGA), reveal a semiconducting ferromagnetic nature in the spin up channel, spotlighting their potential in semiconductor spintronic applications. Phonon dispersion analysis of and revealed positive phonon modes throughout the entire Brillouin zone, confirming their dynamical stability. In contrast, demonstrated dynamical instability. The elastic constants confirm the mechanical stability and ductile nature of the perovskites. Optical and dielectric properties of these perovskites show significant UV absorption and photoconductivity, making them highly suitable for optoelectronic and solar cell applications. Finally, transport properties, such as the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor, and figure of merit (ZT) unveil their exceptional thermoelectric performance. Combining half-metallic ferromagnetic traits with superior thermoelectric and optoelectronic performance positions compounds as exceptional candidates for applications in spintronics, optoelectronics, and thermoelectrics. This comprehensive investigation demonstrates their ability to excel across a diverse array of advanced technological applications. [ABSTRACT FROM AUTHOR]

The present study focused on extracting the anthocyanin dyes in ethanol, acidic ethanol, methanol, and acidic methanol solvents from Nerium oleander flowers by a simple maceration extraction process. FTIR spectroscopy and vibrational studies have confirmed the existence of polyphenolic groups in 2‐phenyl chromenylium (anthocyanin) dyes. The optoelectronic results show the least direct bandgap (2.89 eV), indirect bandgap (1.98 eV), Urbach energy (0.120 eV), high refractive index (1.654), dielectric constant (3.294) and high optical conductivity (1.813 103 S/m) for the anthocyanin dye extracted found in acidic ethanol solvent. The photoluminescence properties such as Stokes' shift, quantum yield, and lifetime results show that anthocyanin dyes are promising candidates for red‐LEDs and optical materials. The excellent correspondence between the absorption and emission spectra reinforces that the anthocyanins are efficient (89%) FRET probes. Further, the donor and acceptor undergo redshift in excitation and emission spectra in all studied solvents. The photometric properties such as CIE, CRI, CCT and color purity results of anthocyanins in all studied solvents revealed that this material exhibits pink to red shades (x = 0.40 → 0.50 and y = 0.46 → 0.39) and is well suitable for have great potential in the manufacturing of Organic‐LEDs and other optoelectronic device applications. [ABSTRACT FROM AUTHOR]

A promising optoelectronic device for light sensing in both the UV and Vis regions is fabricated. This device consists of a nanocomposite resembling coral reefs, termed AgI/polypyrrole‐iodide (AgI/Ppy‐I). The resulting nanocomposite exhibits a hierarchical structure wherein larger particles, comprising smaller particles ~45 nm and an optical bandgap measuring 2.4 eV, form a coral reef‐like morphology. The sensitivity estimation of this constructed optoelectronic device relies on evaluating the current density (Jph) values. Under illumination, a remarkable augmentation in current density (Jph = 0.46 mA cm−2) with a promising value compared to the dark condition's 0.12 mA cm−2. The optical characteristics of this nanocomposite make it highly conducive to efficient UV–Vis light sensing. The values of D (detectivity), reflecting the device's sensitivity, are notably high at 4 × 108 and 3.82 × 108 Jones in the UV and Vis regions, correspondingly. The potential of this photodetector is reinforced by the computed R‐values, which denote the device's responsivity. With values of 1.8 and 1.72 mA W−1 across these two optical regions, correspondingly, it showcases the nanocomposite's effectiveness in transforming incident light into electrical current. Moreover, the appeal of this photodetector extends beyond its performance characteristics. Its cost‐effectiveness, eco‐friendliness, straightforward preparation methodology, scalability for mass production, and high stability collectively. The versatility of this material, coupled with its advantageous attributes, opens avenues for its widespread application, catering to the diverse needs of industries and contributing to the accessibility of efficient optoelectronic devices for a broader audience. [ABSTRACT FROM AUTHOR]

Self‐healing polyvinyl alcohol‐polyacrylic acid (PVA‐PAA) composite films incorporated with molecular iodine (I2) are presented for optoelectronic applications. The incorporation mechanism between the PVA‐PAA donor and I2 acceptor is investigated by studying the chemical, crystal, and morphological properties of the composite films. Incorporating PVA‐PAA composite films with I2 decreases the crystallinity degree of the composite films, which increases the electrical conductivity by enabling the segmental motion in the polymer matrix. PVA‐PAA/I2 composite films are stable at temperatures lower than 200°C, where the majority of optical, optoelectronic, and electrical applications can be realized. Additionally, introducing I2 into the PVA‐PAA matrix increases the melting temperature of the composite films. Moreover, the optical and electrical properties of the PVA‐PAA/I2 composite films are investigated. The bandgap energy of PVA‐PAA film is 3.88 eV, decreasing continuously to 3.38 eV as I2 concentration increases to 16 wt.%. On the other hand, The average conductivity of the PVA‐PAA film is 7.46×10−6S×cm−1. Increasing I2 concentration in the PVA‐PAA matrix increases the electrical conductivity continuously up to 1.33×10−4S×cm−1. The physical properties of the PVA‐PAA/I2 composite films exhibit self‐healing properties after thermal treatment and UV irradiation that occur during the operation cycling in optical, optoelectronic, and electrical applications. [ABSTRACT FROM AUTHOR]

The study of two-dimensional (2D) materials has attracted considerable attention from material scientists globally, mainly because of their distinct electronic, spintronic, magnetic, and optoelectronic characteristics. Transition metal dichalcogenides (TMD) and dihalides (TMDH) are two examples of 2D materials. This study investigates the structural stability, phonon dispersion, electronic, optical, and thermodynamic properties of the unique trigonal osmium diiodide (OsI 2 ) monolayer, which is an example of TMDH. The well-established Density Functional Theory (DFT) is employed for this purpose. We identified an indirect bandgap semiconductor property in this monolayer. The energy bandgap values for GGA-PBE, GGA-PBEsol, and the hybrid functional HSE06 were found to be 1.72, 1.56, and 2.86 eV, respectively. The compound OsI 2 demonstrates structural stability, and studies of phonon dispersion indicate that there are no virtual (negative) phonon frequencies. Furthermore, OsI 2 demonstrates optical absorption within the visible spectrum, making it suitable for optoelectronic applications. However, thermodynamic property calculations have shown that the synthesis of the OsI 2 monolayer would occur naturally at temperatures lower than room temperature, as evidenced by the free energy estimates. [ABSTRACT FROM AUTHOR]

Abstract Photonic integrated circuits (PICs) represent a promising technology for the much-needed medical devices of today. Their primary advantage lies in their ability to integrate multiple functions onto a single chip, thereby reducing the complexity, size, maintenance requirements, and costs. When applied to optical coherence tomography (OCT), the leading tool for state-of-the-art ophthalmic diagnosis, PICs have the potential to increase accessibility, especially in scenarios, where size, weight, or costs are limiting factors. In this paper, we present a PIC-based CMOS-compatible spectrometer for spectral domain OCT with an unprecedented level of integration. To achieve this, we co-integrated a 512-channel arrayed waveguide grating with electronics. We successfully addressed the challenge of establishing a connection from the optical waveguides to the photodiodes monolithically co-integrated on the chip with minimal losses achieving a coupling efficiency of 70%. With this fully integrated PIC-based spectrometer interfaced to a spectral domain OCT system, we reached a sensitivity of 92dB at an imaging speed of 55kHz, with a 6dB signal roll-off occurring at 2mm. We successfully applied this innovative technology to obtain 3D in vivo tomograms of zebrafish larvae and human skin. This ground-breaking fully integrated spectrometer represents a significant step towards a miniaturised, cost-effective, and maintenance-free OCT system.

This study presents a finite element model (FEM) simulation of optoelectronic stimulation in the rat brain, designed to investigate the effects of this emerging neural stimulation technique. A detailed 3D model of the rat brain and an equivalent circuit representation of the organic semiconductor-based stimulation device was used to simulate the subdural application of optoelectronic stimuli to the rat brain. The model is based on realistic electrode geometries and material properties. The stimulated brain volume is approximately 38 mm3 with a maximal stimulation depth of 2.6 mm. Our results indicate that optoelectronic stimulation can achieve targeted activation of cortical neurons. Further studies will focus on optimizing device parameters, exploring long-term effects, and expand this approach for specific neural bioelectronics to fully exploit its potential in clinical applications.

Hydrogen is a promising candidate for green energy sources for future endeavors because of its abundance on Earth. Although its storage is a major challenge for the researchers of this era because of its unsafe and highly explosive nature. The structural, optoelectronic, thermoelectric, vibrational, thermodynamic properties and hydrogen storage capacity of XMgH3 (X = Sr , Ba) are carried out by using the full potential linearized augmented plane wave (FP-LAPW) method in the DFT framework. The theoretical study about these magnesium-based metal hydride perovskites, i.e., SrMgH3 and BaMgH3, declares them structurally stable compounds in space group Pm-3m. The optimization graph for SrMgH3 and BaMgH3 reflects the lowest ground state energy, i.e., −6759 Ry and −16683 Ry, respectively. Comparatively, BaMgH3 seems to be more stable. The electronic band structures and density of states declare them pure metallic due to zero band gap and overlapping of electronic states of the valence and the conduction bands. The electrical conductivity of BaMgH3 increases up to 4. 5 × 1 0 2 0 (Ω ⋅ m ⋅ s) − 1 and thermal conductivity 1. 2 5 × 1 0 1 6 (Ω ⋅ m ⋅ s) − 1 in the temperature range 100 K to 1000 K revealing the good metallic character of BaMgH3. The optical analysis portrays the absorption of compounds in the visible range along with valance shell electrons to the weak bond of hydrogen and dissociates hydrogen molecules at a certain intensity of light. BaMgH3 compound shows minimum scattering and maximum absorption of light in the visible region up to 3 eV. The reflectivity peaks in the visible region 3.0 eV show that 40% of light energy is absorbed due to the opaque nature of BaMgH3. Both these compounds are declared thermodynamically stable due to negative free energy such as −1.20 eV for SrMgH3 and −1.50 eV energy for BaMgH3 at 1000 K, respectively. Moreover, the three acoustic modes showing zero imaginary phonon frequencies at Γ symmetry points predict these compounds' structural and thermodynamical stability. The gravimetric hydrogen storage concentration of SrMgH3 and BaMgH3 is determined as 2.637% and 1.836%, respectively. [ABSTRACT FROM AUTHOR]

For the prosthetic retina, a device replacing dysfunctional cones and rods, with the ability to mimic the spectral response properties of these photoreceptors and provide electrical stimulation signals to activate residual visual pathways, can relay sufficient data to the brain for interpretation as color vision. Organic semiconductors including conjugated polymers with four different bandgaps providing wavelength‐specific electrical responses are ideal candidates for potential full‐color vision restoration. Here, conjugated polymer photocapacitor devices immersed in electrolyte are demonstrated to elicit a photovoltage measured by a Ag/AgCl electrode 100 microns from the device of ≈−40 mV for 15–39 µW mm−2 of incident light power density at three wavelengths: 405 nm for blue photoreceptor candidate material, 534 nm for green, 634 nm for red. Photoresponse is substantially improved by introducing polymer donor/acceptor molecules bulk heterojunctions. Devices with bulk heterojunction configurations achieved at least −70 mV for green candidates with the highest at −200 mV for red cone candidates. These findings highlight the potential for organic materials to bridge the gap toward natural vision restoration for retinal dystrophic conditions such as age‐related macular degeneration, Stargardt disease, or retinitis pigmentosa and contribute to the ongoing advancements in visual prosthetic devices. [ABSTRACT FROM AUTHOR]

Photonic integrated circuits (PICs) represent a promising technology for the much-needed medical devices of today. Their primary advantage lies in their ability to integrate multiple functions onto a single chip, thereby reducing the complexity, size, maintenance requirements, and costs. When applied to optical coherence tomography (OCT), the leading tool for state-of-the-art ophthalmic diagnosis, PICs have the potential to increase accessibility, especially in scenarios, where size, weight, or costs are limiting factors. In this paper, we present a PIC-based CMOS-compatible spectrometer for spectral domain OCT with an unprecedented level of integration. To achieve this, we co-integrated a 512-channel arrayed waveguide grating with electronics. We successfully addressed the challenge of establishing a connection from the optical waveguides to the photodiodes monolithically co-integrated on the chip with minimal losses achieving a coupling efficiency of 70%. With this fully integrated PIC-based spectrometer interfaced to a spectral domain OCT system, we reached a sensitivity of 92dB at an imaging speed of 55kHz, with a 6dB signal roll-off occurring at 2mm. We successfully applied this innovative technology to obtain 3D in vivo tomograms of zebrafish larvae and human skin. This ground-breaking fully integrated spectrometer represents a significant step towards a miniaturised, cost-effective, and maintenance-free OCT system. [ABSTRACT FROM AUTHOR]

The traditional computer with von Neumann architecture has the characteristics of separate storage and computing units, which leads to sizeable time and energy consumption in the process of data transmission, which is also the famous "von Neumann storage wall" problem. Inspired by neural synapses, neuromorphic computing has emerged as a promising solution to address the von Neumann problem due to its excellent adaptive learning and parallel capabilities. Notably, in 2016, researchers integrated light into neuromorphic computing, which inspired the extensive exploration of optoelectronic and all-optical synaptic devices. These optical synaptic devices offer obvious advantages over traditional all-electric synaptic devices, including a wider bandwidth and lower latency. This review provides an overview of the research background on optoelectronic and all-optical devices, discusses their implementation principles in different scenarios, presents their application scenarios, and concludes with prospects for future developments. [ABSTRACT FROM AUTHOR]

The films of P(4ClAni)/CuO, which formed of mixing poly 4-chloroaniline P(4ClAni) by CuO, were fabricated by the casting solution method. The XRD confirmed the successful prepration of the P(4ClAni)/CuO films. Additionally, the effect of CuO on the optical characteristics was determined. The CuO increased the refractive index from 1.09 for P(4ClAni) to 1.11 for P(4ClAni)/CuO-1, and 1.19 for P(4ClAni)/CuO-3, respectively, while the oscillation energy E0 dropped from 4.29 eV for P(4ClAni) to 3.57 eV for P(4ClAni)/CuO-1, 3.12 eV for P(4ClAni)/CuO-2, and 3.06 eV for P(4ClAni)/CuO-3. The charge transfer between P(4ClAni) and CuO increased optical conductivity as the CuO ratios increased. This suggests that modifications in the electronic structure of the composite due to the interactions between P(4ClAni) and CuO. Also, the plasma frequency increased from 0.87 x 1012 s−1 to 2.32 x 1012 s−1. These changes in optical parameters occurred when the polarization of the P(4ClAni)/CuO was altered. The study elucidated the advantages of incorporating CuO nanoparticles as fillers in improving the properties of P(4ClAni) structures. The obtained results indicate the P(4ClAni)/CuO composites were sucessfuly fabricated with novel characteristics that can be applied in flexible optical devices. [ABSTRACT FROM AUTHOR]

Conducting polymers have attracted significant interest due to their unique properties, including metal-like conductivity, ionic conductivity, optical transparency, and mechanical flexibility. Poly(3,4-ethylene-dioxythiophene):poly(styrene sulfone) (PEDOT:PSS) is commonly utilized as the hole transport layer (HTL) in optoelectronic devices. However, its high acidity, primarily attributed to the low pH of PSS, poses challenges such as counter electrode etching, detrimental interactions with the photoactive layer, and device instability. To address these issues, researchers are exploring alternative HTL materials and deposition methods. Oxidative chemical vapor deposition (oCVD) has emerged as a promising technique to fabricate high-quality PEDOT thin films without PSS, enhancing device stability. The selection of an appropriate oxidant is crucial in oCVD, as it significantly influences film properties and performance. The utilization of liquid oxidants enables direct integration of conductive polymer thin films into devices through a one-step, dry process, eliminating the need for post-deposition rinsing and ensuring compatibility with solvent-sensitive and temperature-sensitive substrates. Moreover, precise control over liquid oxidant flow rates provides advantages over solid oxidants. This prospective article provides an overview of recent advancements in engineering the texture and nanostructure of conducting polymers to boost electrical conductivity and enhance optoelectronic performance. Additionally, it provides a comprehensive overview of recent progress in oCVD method, focusing on the use of liquid oxidants. Furthermore, the prospective article underscores the significance of oCVD in the efficient fabrication of PEDOT thin films without PSS, thus playing a pivotal role in the development of stable optoelectronic devices. [ABSTRACT FROM AUTHOR]

This paper presents a novel optoelectronic transimpedance amplifier (OTA) for short-range LiDAR sensors used in 180 nm CMOS technology, which consists of a main transimpedance amplifier (m-TIA) with an on-chip P+/N-well/Deep N-well avalanche photodiode (P+/NW/DNW APD) and a replica TIA with another on-chip APD, not only to acquire circuit symmetry but to also obtain concurrent automatic gain control (AGC) function within a narrow single pulse-width duration. In particular, for concurrent AGC operations, 3-bit PMOS switches with series resistors are added in parallel with the passive feedback resistor in the m-TIA. Then, the PMOS switches can be turned on or off in accordance with the DC output voltage amplitudes of the replica TIA. The post-layout simulations reveal that the OTA extends the dynamic range up to 74.8 dB (i.e., 1 µApp~5.5 mApp) and achieves a 67 dBΩ transimpedance gain, an 830 MHz bandwidth, a 16 pA/ √ Hz noise current spectral density, a −31 dBm optical sensitivity for a 10−12 bit error rate, and a 6 mW power dissipation from a single 1.8 V supply. The chip occupies a core area of 200 × 120 µm2. [ABSTRACT FROM AUTHOR]

This study investigates the impact of spin-coating speed on the performance of carbon nanotube (CNT)-based optoelectronic synaptic devices, focusing on their long-term memory properties. CNT films fabricated at lower spin speeds exhibited a greater thickness and density compared to those at higher speeds. These denser films showed enhanced persistent photoconductivity, resulting in higher excitatory postsynaptic currents (EPSCs) and the prolonged retention of memory states after UV stimulation. Devices coated at a lower spin-coating speed of 2000 RPM maintained EPSCs above 70% for 3600 s, outperforming their higher-speed counterparts in long-term memory retention. Additionally, the study demonstrated that the learning efficiency improved with repeated UV stimulation, with fewer pulses needed to achieve the maximum EPSC in successive learning cycles. These findings highlight that optimizing spin-coating speeds can significantly enhance the performance of CNT-based synaptic devices, making them suitable for applications in neuromorphic computing and artificial neural networks requiring robust memory retention and efficient learning. [ABSTRACT FROM AUTHOR]

The relentless advancement of van der Waals (vdW) heteroepitaxy technology has charted an expansive horizon for the integration and functionalization of heterogeneous materials. In this research, a 2D/3D vdW heterojunction photodetector based on p‐W0.09Re0.91S2/n‐GaN integrated on a Free‐standing (FS)‐GaN substrate, encompassing horizontal, quasi‐vertical, and vertical structures is have successfully fabricated. By incorporating a suite of performance enhancement strategies, including mixed‐dimensional stacking, p‐type doping, type‐II band alignment, and vertical structure design, the developed vertical structure photodetector has exhibited exceptional performance. Specifically, the detector achieves a high Responsivity of up to 497.60 A W−1, an impressive specific Detectivity of 8.41 × 1013 Jones, and a fast response speed (rise/decay time of 10 ms/20 ms). Additionally, the device is successfully applied in the realm of single‐pixel imaging, substantiating its potential for practical applications. The findings of this work not only signify notable strides in integration and optoelectronic performance within the optoelectronic device domain but also portend novel breakthroughs in imaging technology applications, bestowing renewed vigor and endless potential upon the evolution of this field. [ABSTRACT FROM AUTHOR]

The following work presents a theoretical study on new quaternary Heusler compounds called TaAlCuCo under varying pressures from 0 to 100 GPa. The study comprehensively investigates the material's structural, elastic, mechanical, electronic, optical, and vibrational properties. The results reveal that as the applied pressure increases, the lattice parameters of TaAlCuCo decrease from 6.058465 to 5.476836 Å. Furthermore, the material exhibits desirable characteristics such as ductility, metallic bonding, and stability even under high pressure. Notably, TaAlCuCo demonstrates anisotropic behavior, indicating that its properties vary depending on the measurement direction. The study also observes a widening of the material's bandgap from 0.010 to 0.333 eV with increasing pressure, suggesting a decline in conductivity. Additionally, TaAlCuCo exhibits favorable optical properties, including a high refractive index, absorption, reflectivity, and conductivity, thereby indicating its potential as a UV filter and for use optoelectronic devices. [ABSTRACT FROM AUTHOR]

The negative environmental impact of fossil fuel and the ever-increasing need for renewable energy materials necessitate a rigorous search for optoelectronic materials. Photon reabsorption due to a small Stokes shift limits the light-emitting potentials of many optical materials. In this research, two benzimidazole Schiff bases, 3-(((1H-benzo[d]imidazol-2-yl)imino)methyl)phenol (1) and N-(1H-benzo[d]imidazole(-2-yl)-1-(3-nitrophenyl))methanimine (2), were synthesized via one-pot single-step condensation and characterized using spectrometric (1H NMR, 13C NMR, HRMS and FTIR) techniques. The optoelectronic, nonlinear optical (NLO), adsorption properties and natural bond orbital (NBO) analysis of 1 and 2 were explored using spectroscopic, density functional theory (DFT) and Monte Carlo (MC) simulation approaches. The absorption, light-harvesting efficiency (LHE) and fluorescence properties were studied in solution. Static and dynamic first and second hyperpolarizabilities and parameters for power conversion efficiency (Voc and ΔGinj) were computed using the time-dependent DFT/B3LYP/6–311++G(d,p) method. Hyperpolarizabilities were compared with those of urea (standard). The binding properties of 1 and 2 on TiO2 (anatase 101) were investigated using the MC method. The calculated electronic properties agree with the experimental results. The compounds display large Stokes shifts (> 200 nm), appreciable quantum yields and low band gaps. High LHE (87%) and large hyperpolarizabilities were obtained for 2. Dye 2 displayed a high Voc, while 1 exhibited a more negative ΔGinj. The negative adsorption energies of the 1-TiO2 (− 52.9 kJ/mol) and 2-TiO2 (– 57.1 kJ/mol) interfaces indicate their strong binding interactions with anatase. NBO analysis revealed that conjugation and hyperconjugation were the primary interactions responsible for the stabilization of the dyes. These dyes have the potential for use in optoelectronic and nonlinear optical applications. [ABSTRACT FROM AUTHOR]

This paper presents a novel power-efficient topology for receivers in short-range LiDAR sensors. Conventionally, LiDAR sensors exploit complex time-to-digital converters (TDCs) for time-of-flight (ToF) distance measurements, thereby frequently leading to intricate circuit designs and persistent walk error issues. However, this work features a fully differential trans-impedance amplifier with on-chip avalanche photodiodes as optical detectors so that the need of the following post-amplifiers and output buffers can be eliminated, thus considerably reducing power consumption. Also, the combination of amplitude-to-voltage (A2V) and time-to-voltage (T2V) converters are exploited to replace the complicated TDC circuit. The A2V converter efficiently processes weak input photocurrents ranging from 1 to 50 μApp which corresponds to a maximum distance of 22.8 m, while the T2V converter handles relatively larger photocurrents from 40 μApp to 5.8 mApp for distances as short as 30 cm. The post-layout simulations confirm that the proposed LiDAR receiver can detect optical pulses over the range of 0.3 to 22.8 m with a low power dissipation of 10 mW from a single 1.8 V supply. This topology offers significant improvements in simplifying the receiver design and reducing the power consumption, providing a more efficient and accurate solution that is highly suitable for short-range LiDAR sensor applications. [ABSTRACT FROM AUTHOR]

This study investigated the effect of alkaline-earth metals (X = Be, Mg, Ca) substitution of BFe 2 XH perovskite materials and the potential applications for hydrogen storage utilizing density functional theory (DFT) approach at the GGA-PBE and the HSE06 methods. The mechanical properties of the studied systems demonstrate the mechanical stability of BFe 2 MgH, making it the most mechanically robust compound. While the Pugh ratio suggests that BFe 2 BeH was brittle, while BFe 2 CaH showed greater ductility, anisotropic factors confirm that all compounds are anisotropic, indicating directional dependence in their properties. The electronic band structure analysis using the HSE06 and the GGA-PBE suggests that the studied perovskites are metallic due to a calculated bandgap of zero. In terms of optical/optoelectronic properties, BFe 2 MgH exhibits the highest optical conductivity, absorption coefficient, and energy loss function, indicating its superior ability to absorb light and transfer electrons. For practical applications, the hydrogen storage capacity is assessed, with BFe 2 BeH showing the highest gravimetric and volumetric capacities. These promising results suggest the potential use of BFe 2 BeH as an efficient material for hydrogen storage. • This study investigated the effect of alkaline-earth metals (X = Be, Mg, Ca) substitution of BFe 2 XH perovskite materials. • The study utilized density functional theory (DFT) approach at the GGA-PBE and the HSE06 methods. • The mechanical properties of the studied systems demonstrate the mechanical stability of BFe 2 MgH. • The electronic band structure analysis was performed using HSE06 and the GGA-PBE. • BFe 2 MgH exhibits the highest optical conductivity, absorption coefficient, and energy loss function. [ABSTRACT FROM AUTHOR]

Background: Myotonic dystrophy type 1 (DM1) is a rare multisystemic genetic disorder with motor hallmarks of myotonia, muscle weakness and wasting. DM1 patients have an increased risk of falling of multifactorial origin, and proprioceptive and vestibular deficits can contribute to this risk. Abnormalities of muscle spindles in DM1 have been known for years. This observational cross-sectional study was based on the hypothesis of impaired cervical proprioception caused by alterations in the neck spindles. Methods: Head position sense was measured in 16 DM1 patients and 16 age- and gender-matched controls. A head-to-target repositioning test was requested from blindfolded participants. Their head was passively rotated approximately 30° leftward or rightward and flexed or extended approximately 25°. Participants had to replicate the imposed positions. An optoelectronic system was adopted to measure the angular differences between the reproduced and the imposed positions (joint position error, JPE, °) concerning the intended (sagittal, horizontal) and unintended (including the frontal) planar projections. In DM1 patients, JPEs were correlated with clinical and balance measures. Static balance in DM1 patients was assessed through dynamic posturography. Results: The accuracy and precision of head repositioning in the intended sagittal and horizontal error components did not differ between DM1 and controls. On the contrary, DM1 patients showed unintended side-bending to the left and the right: the mean [95%CI] of frontal JPE was −1.29° [−1.99°, −0.60°] for left rotation and 0.98° [0.28°, 1.67°] for right rotation. The frontal JPE of controls did not differ significantly from 0° (left rotation: 0.17° [−0.53°, 0.87°]; right rotation: −0.22° [−0.91°, 0.48°]). Frontal JPE differed between left and right rotation trials (p < 0.001) only in DM1 patients. No correlation was found between JPEs and measures from dynamic posturography and clinical scales. Conclusions: Lateral head bending associated with head rotation may reflect a latent impairment of neck proprioception in DM1 patients. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskite compounds attract tremendous research attention due to their remarkable and interesting optoelectronic properties and high power conversion efficiency (PCE). This work aims to predict various properties of some new halide perovskites RbKTiX6 (X = Cl, Br, I) to investigate their feasibility as active materials for energy storage and photovoltaic application. The Density Functional Theory (DFT) implemented in the Quantum Espresso code was applied to calculate the materials' properties, including the optoelectronic and transport properties. The evaluation of their calculated structural parameters reveals that the perovskites are highly stable, both chemically and mechanically and that there is a decline in the lattice constant and the Ti-X bond length when the I anion is substituted with its isoelectronic i.e. Br and Cl. From their electronic band structure, the materials are projected to be direct-gap semiconducting materials with energy gap ranging from 0.77 eV to 2.3 eV. Strong light absorption (up to 105 cm−1) in ultraviolet–visible regions is predicted for all studied perovskites, which is crucial for solar cell applications. This is also supported by their low reflectivity (below 23%). To investigate the power conversion efficiency (PCE) of these materials, we suggest n-i-p solar cells diagram, using RbKTiX6 (X = Cl, Br, I) as the light absorber. The calculated PCE values of RbKTiCl6, RbKTiBr6 and RbKTiI6 are ƞ = 10.03%, ƞ = 7.21% and ƞ = 4.18%, respectively. Finally, it is found that the perovskites exhibit high thermo-power convergence efficiency, as indicated by their thermoelectric figure of merit which is near unity. [ABSTRACT FROM AUTHOR]