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A high solar cell efficiency of 32%, water-splitting for hydrogen generation, optoelectronics, and super-exchange coupling in Ba2MnTiO6: a DFT and AIMD study.

Recently, double perovskite oxides (DPO) have gained much interest due to their wide range of technological applications in various demanding fields of energy conversion. Here, we present a comprehensive theoretical study of several physical properties of a lead-free Ba2MnTiO6 DPO. The structural stability is validated by computing the formation enthalpy, elastic parameters, and phonon dispersion curves. Additionally, the ab initio molecular dynamics simulations carried out indicate stable energy oscillations without any drifting and structural degradation, further confirming the thermal stabi

Magnetic exchange and valence delocalization in a mixed valence [Fe2+Fe3+Te2]+ complex: insights from theory and interpretations of magnetic and spectroscopic data.

A mixed valence binuclear Fe2.5+-Fe2.5+ (Robin-Day Class III) transition metal complex, [Fe2.5+μTe2Fe2.5+]1-, composed of two FeN2Te2 pseudo-tetrahedral units with μ-bridging Te2- ligands was reported to exist in an unprecedented S = 3/2 ground state (Nature Chemistry, https://doi.org/10.1038/s41557-021-00853-5). For this and the homologous complexes containing Se2- and S2-, the Anderson-Hasegawa double exchange spin-Hamiltonian was broadly used to interpret the corresponding structural, spectroscopic and magnetic data. First principles multireference ab initio calculations are used here to si

Exploring strain-induced variations in electronic structure and optical properties of MoSi2N4/WSSe heterostructure.

CONTEXT: The development of two-dimensional van der Waals heterostructures for optoelectronic and photocatalytic applications demands precise control over band alignment and light absorption. This study addresses the challenge of engineering strain-tunable electronic properties in the MoSi2N4/WSSe heterostructure, a system exhibiting intrinsic type-I band alignment and a direct band gap of 1.850 eV. We demonstrate that interfacial charge transfer of 0.0831 |e| from MoSi2N4 to WSSe generates a robust internal electric field, significantly enhancing charge separation and transport. Crucially, co

Terahertz Time-Domain Spectroscopy as a Defect Fingerprinting Tool for Halide Perovskite Solar Cells: Toward a Universal Framework.

Organic-inorganic hybrid perovskites (OHPs) deliver certified single-junction power conversion efficiencies (PCEs) of up to 27.3% and National Laboratory of the Rockies (NLR)-certified perovskite-silicon tandem values of 34.85%, yet a substantial gap with the Shockley-Queisser (S-Q) limit persists. Grain-boundary (GB) defects are one principal contributor to this gap, driving non-radiative recombination, ion migration, and degradation alongside bulk, interfacial, contact-related, phase-related, and environmental loss channels. Rational passivation demands a non-contact tool capable of identify

Design principles for (efficient) excited-state absorption-based blue-to-UV upconversion phosphors with Pr3.

UV light generation is generally not very efficient, expensive, or may even require toxic elements such as mercury. In contrast, blue light (λ = 450 nm) is cheaply available from semiconductor LEDs and its use in phosphor-converted LEDs is technologically mature and could be envisioned as an intense, sustainable light source in an upconversion scheme. The electronic energy level landscape of the 4f2 ion Pr3+ does allow such a blue-to-UV upconversion (UC) by resonantly exciting the 3P J (J = 0, 1, 2) levels with blue light, followed by absorption of a second blue photon, thus populating the 4f1

Disorder-Engineered Thermoelectric Cu2Se/SnSe2 Heterojunctions Embedded in Glycyrrhizic Acid Hydrogels for Pyro-Photo-Ultrasonic Therapy of Periodontitis.

Periodontitis treatment is severely hampered by rapid electron-hole recombination and hypoxic microenvironment, which fundamentally limit reactive oxygen species (ROS) yields in conventional photo/sonodynamic therapies. Herein, we propose a disorder-engineered thermoelectric heterojunction strategy that couples pyro-photo-ultrasonic effects to overcome these bottlenecks. Thermoelectric Cu2Se(CuSe)/SnSe2 heterojunctions, synthesized by mechanochemical ball milling, introduce dense CuSe nanodomains and interfacial defects that serve simultaneously as phonon-scattering centers (minimizing thermal

Electronic Structure and Vibrational Properties of Indenotetracene-Based Crystal.

Asymmetrically substituted indenotetracene crystals are promising nonfullerene electron transport materials for organic photovoltaics, offering potential improvements in efficiency and stability. In this work, we present a first-principle investigation of the electronic and vibrational properties of a diarylindenotetracene system functionalized with two methoxy groups (hereafter DimethoxyASI). Single-crystal X-ray diffraction analysis [reported in J. Org. Chem. 2018, 83, 4, 1828] reveals a monoclinic P2 1 / c $$ {\mathrm{P}2}_1/\mathrm{c} $$ structure with an interplanar distance of 3.76

Elucidating the Magnetoelastic Coupling, Pressure-Dependent Magnetic Behavior, and Anomalous Hall Effect in FexTi2S4 Intercalation Sulfides.

Transition-metal chalcogenides with intercalated layered structures are interesting systems in material physics due to their attractive electronic and magnetic properties, with applications in the fields of magnetic refrigerators, catalysts, and thermoelectrics, among others. In this work, we studied in detail the structural, electronic, and magnetic properties of (Fe,Ti)-based sulfides with formula FexTi2S4 (x = 0.24, 0.32, and 0.42), prepared as polycrystalline materials under high-pressure conditions. They present a layered Heideite-type crystal structure, as assessed by synchrotron X-ray d

Does an infrasonic acoustic shock wave resonance of the manganese 3+ loaded/copper depleted prion protein initiate the pathogenesis of TSE?

Intensive exposures to natural and artificial sources of infrasonic acoustic shock (tectonic disturbances, supersonic aeroplanes, etc.) have been observed in ecosystems supporting mammalian populations that are blighted by clusters of traditional and new variant strains of transmissible spongiform encephalopathy (TSE). But TSEs will only emerge in those 'infrasound-rich' environments which are simultaneously influenced by eco-factors that induce a high manganese (Mn)/low copper (Cu)-zinc (Zn) ratio in brains of local mammalian populations. Since cellular prion protein (PrPc) is a cupro-protein

First-principles investigation of Pd-based Kesterites for optoelectronic and photovoltaic applications.

CONTEXT: In this article, we report a first-principles study of the structural, electronic, optical, and photovoltaic properties of the earth-abundant quaternary Kesterites Cu2PdSnSe2 (CPTSe) and Cu2PdSnS4 (CPTS). Dynamical and thermal stability of these compounds were assessed through phonon dispersion and ab-initio molecular dynamics (AIMD) calculations. The calculated band structures revealed that both materials are direct band gap semiconductors with gaps of 1.11 eV (for CPTSe) and 1.40 eV (for CPTS). Spin-orbit coupling (SOC) calculations reveal that the effect is limited only to minor ba

First-principles study of rare-earth-free Cs4SrI6:Tl, a zero-dimensional halide perovskite for scintillation applications.

In recent years, rare-earth-activated perovskite scintillators have drawn significant research attention owing to their characteristic and efficient 4f n ↔ 4f n-15d electronic transitions. However, the high cost and limited readiness of rare-earth elements motivate the search for alternative activators. In this context, thallium ions (Tl+) can offer a promising activator that can act as a two-level luminescent center, yielding characteristic emissions through 6s16p1 → 6s2 electronic transitions, similar to the well-known NaI:Tl scintillator while remaining cost-effective. In this investigation

Synthesis of highly efficient novel two-step spatial 2D photocatalyst material WS2/ZnIn2S4 for degradation/reduction of various toxic pollutants.

In this article, we report the synthesis, characterization of novel biofriendly 2D/2D heterostructure WS2/ZnIn2S4 material in which 2D WS2 nanosheets are uniformly distributed spatially onto the spherically arranged 2D leaves of ZnIn2S4. We then studied the in-depth photocatalytic degradation activity of this novel nanocomposite and its pristine component materials on cationic dye: malachite green, anionic dye: congo red and reduction of heavy metal: chromium(VI) and the degradation efficiency of composite material was also tested on rhodamine-B, methylene blue, methyl orange dyes and acetamin

Recent Advances in Air-Stable n-Type Single-Walled Carbon Nanotube Composites for Thermoelectric Applications.

With the rapid advancement of the IoT society and growing awareness of environmental issues, thermoelectric conversion technology-which directly converts waste heat into electricity-is gaining attention as a self-powered, autonomous power source capable of driving countless devices. While currently mainstream metal-based inorganic thermoelectric materials demonstrate high performance, their high rigidity and brittleness, as well as their frequent inclusion of toxic heavy metals, have limited their application in biological systems and on curved surfaces. As a next-generation alternative, singl

First-principles study of band gap engineering and thermoelectric performance in K2AgSbX6 (X = Cl, F, I) double perovskites.

This study presents a comprehensive density functional theory (DFT) investigation of the double perovskite compounds K2AgSbX6 (X = Cl, F, I) using the generalized gradient approximation (GGA) and modified Becke-Johnson (mBJ) exchange-correlation functionals. The electronic, optical, elastic, and thermoelectric properties of these materials have been systematically analyzed to evaluate their potential for photovoltaic and thermoelectric applications. The novelty of this work lies in the comparative band-gap engineering of K2AgSbX6 through halide substitution, together with a combined assessment

Predicting Molecular Crystal Properties from First Principles: Finite-Temperature Thermochemistry to NMR Crystallography.

Molecular crystals occur widely in pharmaceuticals, foods, explosives, organic semiconductors, and many other applications. Thanks to substantial progress in electronic structure modeling of molecular crystals, attention is now shifting from basic crystal structure prediction and lattice energy modeling toward the accurate prediction of experimentally observable properties at finite temperatures and pressures. This Account discusses how fragment-based electronic structure methods can be used to model a variety of experimentally relevant molecular crystal properties. First, it describes the cou

Unconventional Clathrates with Transition Metal-Phosphorus Frameworks.

In this Account, we focused on a unique class of inclusion compounds, intermetallic clathrates, which exist in a variety of structures and exhibit diverse physical properties. These compounds combine covalent tetrahedral frameworks with rattling guest atoms situated inside their framework cages. Tetrels, the group 14 elements, are the basis for conventional clathrates because they fulfill the bonding requirement of four electrons per framework atom. In analogy to the replacement of Ge with GaAs in semiconductors, we focused on unconventional tetrel-free clathrates with frameworks composed of p

Molecular Gridization of Organic Semiconducting π Backbones.

ConspectusOrganic π-conjugated molecules and polymers have emerged as some of the most promising candidates of semiconductors for future information, intelligent technology, and smart manufacturing because of their unique properties such as structural diversity, flexibility, stretchability, ultrathinness, light weight, low-cost and large-area fabrication procedures, and excellent biocompatibility. However, several severe challenges remain, including inferior optical and electronic properties compared to inorganic materials, poor stability and lifespan, low yields in solution processing pattern

Преобразование фотоэнергетики в наноматериалах для точной терапостики.

Быстро развивающаяся область тераностистики направлена на интеграцию терапевтических и диагностических функций в единую платформу для точной медицины, позволяющую одновременно лечить и контролировать болезни. Наноматериалы, основанные на преобразовании фотоэнергии, стали разносторонней платформой, использующей уникальные свойства света для активации тераностистики с высокой пространственной и временной точностью. В настоящем обзоре содержится всеобъемлющий обзор последних изменений в области преобразования фотоэнергетики с использованием наноматериалов с уделением особого внимания их применени

Ta-induced electronic reconstruction in CaSiO3: wide-band-gap modulation, emergent metallic behavior, and multifunctional response from first-principles.

A comprehensive first-principles investigation was conducted to clarify the impact of Ta substitution at the Si site on the structural, electronic, optical, thermoelectric, mechanical, and magnetic properties of CaSiO3. The pristine cubic model has an optimized lattice parameter of 3.607 Å, whereas Ta incorporation at 12.5% and 25% preserves the host framework while inducing local B-O coordination rearrangement. The equilibrium volume increases from 2533.4554 Bohr3 for pristine CaSiO3 to 2755.1025 and 3155.7362 Bohr3 for the 12.5% and 25% Ta-substituted systems, respectively. The EOS-derived b

Innovative Approaches in Bone Tissue Engineering: Strategies for Cancer Treatment and Recovery.

Cancer has rapidly emerged as a leading global cause of premature mortality, with significant economic implications projected to reach USD 25.2 trillion from 2020 to 2050. Among the various types of cancer, primary bone cancers, though uncommon, are projected to see nearly 4000 new cases diagnosed in the United States in 2024. The complexity of treating bone cancer arises from its rarity, diversity, and the challenges associated with surgical interventions, metastatic spread, and post-operative complications. Advancements in bone tissue engineering (BTE) have introduced innovative therapeutic

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… Phonons and thermal transport in graphene and graphene-based materials. Rep. Prog. Phys. 2017;80:036502. doi: 10.1088/1361-6633/80/3/036502. 110. Peng Z., Zhao T., Zhou Y., Li S., Li J., Leblanc R.M. Bone tissue engineering via carbon?based nanomaterials. Adv. Healthc. …