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We consider the electron stimulated desorption, via dissociative electron attachment, of anionic species from thin condensed CD4 films deposited on a Pt substrate and compare experimentally observed desorption yields with density functional theory calculations of the binding energies of various anionic and neutral moieties to Pt(111). Certain species (which can be considered chemisorbed) exhibit very high binding energies and large charge transfer with the substrate. Other "physisorbed" species have much lower binding energies. Species that chemisorb have lower desorption yields than those that physisorb, especially at 1–2 monolayer coverage of the Pt substrate. The binding energy of D− to Pt is the weakest, and experimentally, the desorption yield is the highest regardless of the thickness of CD4. The calculations show that the formation and desorption of anionic species at a distance of 16 Å from the substrate, which is equivalent to the thickness of CD4 films of four monolayers, are not influenced by the short-range interactions between the substrate and the molecule and DEA products. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D)/three-dimensional (3D) halide perovskite heterostructures have been extensively studied for their ability to combine the outstanding long-term stability of 2D perovskites with the superb optoelectronic properties of 3D perovskites. While current studies mostly focus on vertically stacked 2D/3D perovskite heterostructures, a theoretical understanding regarding the optoelectronic properties of 2D/3D perovskite lateral heterostructures is still lacking. Herein, we construct a series of 2D/3D perovskite lateral heterostructures to study their optoelectronic properties and interfacial charge transfer using density functional theory (DFT) calculations. We find that the band alignments of 2D/3D heterostructures can be regulated by varying the quantum-well thickness of 2D perovskites. Moreover, decreasing the 2D component ratio in 2D/3D heterostructures can be favorable to form type-I band alignment, whereas a large component ratio of 2D perovskites tends to form type-II band alignment. We can improve the amount of charge transfer at the 2D/3D perovskite interfaces and the light absorption of 2D perovskites by increasing quantum-well thickness. These present findings can provide a clear designing principle for achieving 3D/2D perovskite lateral heterostructures with tunable optoelectronic properties. [ABSTRACT FROM AUTHOR]

Using the density functional theory, we conducted a study on the electrification upon contact between hydrophobic liquid molecules and water molecules, revealing localized characteristics of contact-electrification. These "localized features" refer to the specific microscale characteristics where electron transfer predominantly occurs at the contact regions, influenced by factors such as atomic distances and molecular orientations. Although the electrostatic potential and the highest occupied molecular orbital–lowest unoccupied molecular orbital gap offer substantial predictive insights for electron transfer across polymer interfaces, they fall short in capturing the complexities associated with the interaction between hydrophobic liquids and water molecules. The electronegativity of elements at the interface and the localization of molecular orbitals play a decisive role in electron transfer. Simultaneously, for liquid molecules with irregular structures, there is no correlation between the "contact area" and the amount of electron transfer. The "contact area" refers to the surface region where two different liquid molecules come into close proximity. It is defined by the surface area of atoms with interatomic distances smaller than the van der Waals radius. This study challenges traditional assumptions about contact-electrification, particularly in liquid–liquid interfaces, providing new insights into the localized nature of this phenomenon. [ABSTRACT FROM AUTHOR]

Metal–Organic Polymers (MOPs) have attracted growing attention for lithium-ion battery (LIB) applications due to their merits in orderly ionic transportation and robust structure stability in electrochemical reactions. However, they suffer from poor electronic conductivity. In this work, we apply first-principles density functional theory to explore the potential of three one-dimensional (1D) electrically conductive C6H2S4TM (TM = Fe, Co, and Ni) MOPs with the π–d conjugated coordination as anode materials for Li+ ions storage. Our theoretical results reveal that these 1D MOPs possess a superior theoretical capacity of over 748 mA h g−1. In particular, the 1D C6H2S4Ni MOP shows an exceptional theoretical specific capacity of 1110 mA h g−1 based on the three-electron transferring reaction, which significantly outperforms the traditional graphite-based anode material in LIBs. Moreover, the resonant charge transfer between Ni metal and ligand within the 1D C6H2S4Ni MOP reduces the diffusion energy barrier of the Li atoms when they migrate on the surface of the MOP. The ultrahigh theoretical specific capacity of the C6H2S4Ni MOP predicts that it can be a promising anode material for LIBs. [ABSTRACT FROM AUTHOR]

ReaxFF reactive force field bridges the gap between nonreactive molecular simulations and quantum mechanical calculations and has been widely applied during the past two decades. However, its application to earth materials, especially those under high T-P conditions relevant to Earth's interior, is still limited due to the lack of available parameters. Here, we present the development and validation of a ReaxFF force field containing several of the most common elements in Earth's crust, i.e., Si/Al/O/H/Na/K. The force field was trained against a large data set obtained from density functional theory (DFT) calculations, including charges, bond/angle distortion curves, equation of states, ion migration energy profiles, and condensation reaction energies. Different coordination environments were considered in the training set. The fitting results showed that the current force field can well reproduce the DFT data (the Pearson correlation coefficient, Rp, is 0.95). We validated the force field on mineral–water interfaces, hydrous melts/supercritical geofluids, and bulk crystals. It was found that the current force field performed excellently in predicting the structural, thermodynamic, and transport properties of various systems (Rp = 0.95). Moreover, possible applications and future development have been discussed. The results obtained in this study suggest that the current force field holds good promise to model a wide range of processes and thus open opportunities to advance the application of ReaxFF in earth material modeling. [ABSTRACT FROM AUTHOR]

Controlling triplet states is crucial to improve the efficiency and lifetime of organic room temperature phosphorescence (ORTP). Although the intrinsic factors from intramolecular radiative and non-radiative decay have been intensively investigated, the extrinsic factors that affect triplet exciton quenching are rarely reported. Diffusion to the defect sites inside the crystal or at the crystal surface may bring about quenching of triplet exciton. Here, the phosphorescence lifetime is found to have a negative correlation with the triplet exciton diffusion coefficient based on the density functional theory (DFT)/time-dependent density functional theory (TD-DFT) calculations on a series of ORTP materials. For systems with a weak charge transfer (CT) characteristic, close π–π stacking will lead to strong triplet coupling and fast triplet exciton diffusion in most cases, which is detrimental to the phosphorescence lifetime. Notably, for intramolcular donor–acceptor (D–A) type systems with a CT characteristic, intermolecular D–A stacking results in ultra-small triplet coupling, thus contributing to slow triplet diffusion and long phosphorescence lifetime. These findings shed some light on molecular design toward high-efficiency long persistent ORTP. [ABSTRACT FROM AUTHOR]

Golden nanoparticle dimers connected by conjugated molecular linkers 1,2-bis(2-pyridyl)ethylene are produced. The formation of stable dimers with 22 nm diameter nanoparticles is confirmed by transmission electron microphotography. The possibility of charge transfer through the linkers between the particles in the dimers is shown by the density functional theory calculations. In addition to localized plasmon resonance of solitary nanoparticles with a wavelength of 530 nm, the optical spectra exhibit a new intense absorption peak in the near-infrared range with a wavelength of ∼780 nm. The emergent absorption peak is attributed to the charge-transfer plasmon (CTP) mode; the spectra simulated within the CTP developed model agree with the experimental ones. This resonant absorption may be of interest to biomedical applications due to its position in the so-called transmission window of biological tissues. The in vitro heating of CTP dimer solution by a laser diode with a wavelength of 792 nm proved the efficiency of CTP dimers for achieving a temperature increase of ΔT = 6 °C, which is sufficient for hyperthermia treatment of malignant tumors. This indicates the possibility of using hyperthermia to treat malignant tumors using the material we synthesized. [ABSTRACT FROM AUTHOR]

Gold nanoclusters have attracted significant attention due to their unique physical-chemical properties, which can be tuned by alloying with elements such as Cu, Pd, Ag, and Pt to design materials for various applications. Although Au-nanoalloys have promising applications, our atomistic understanding of the descriptors that drive their stability is far from satisfactory. To address this problem, we considered 55-atom model nanoalloys that have been synthesized by experimental techniques. Here, we combined data mining techniques for creating a large sample of representative configurations, density functional theory for performing total energy optimizations, and Spearman correlation analyses to identify the most important descriptors. Among our results, we have identified trends in core–shell formation in the AuCu and AuPd systems and an onion-like design in the AuAg system, characterized by the aggregation of gold atoms on nanocluster surfaces. These features are explained by Au's surface energy, packing efficiency, and charge transfer mechanisms, which are enhanced by the alloys' preference for adopting the structure of the alloying metal rather than the low-symmetry one presented by Au55. These generalizations provide insights into the interplay between electronic and structural properties in gold nanoalloys, contributing to the understanding of their stabilization mechanisms and potential applications in various fields. [ABSTRACT FROM AUTHOR]

Early cancer diagnosis strongly relies on finding appropriate materials for the detection of respected biomarkers. For the first time, we have theoretically investigated the capability of the MoSe2 monolayer to detect three lung cancer biomarkers, including hexanal, nonanal, and p-cresol. To this end, adsorption performance, bandgap alteration, and charge transfer of the MoSe2 monolayer upon exposure to the three biomarkers were studied using density functional theory. The results, in all cases, indicate that the charge transfer is from the monolayer to the adsorbed biomarkers, and the adsorption of biomarkers decreases the bandgap of the monolayer, approving the p-type sensing character of the MoSe2 monolayer. This is in complete agreement with the band structure analysis of the material and the previous reports in the literature. Our findings demonstrated the appropriate performance of the MoSe2 monolayer in terms of the physisorption of the lung cancer biomarkers and desirable recovery times in the desorption process. Further performance enhancement of MoSe2 as a lung cancer biosensor can be the subject of future studies. [ABSTRACT FROM AUTHOR]

The effects of Mn and As doping in β-FeSi2 have been studied by theoretical simulations and electrical characterizations by analyzing Hall parameters within the temperature range of 20–300 K using mobility and the dual band model. The Hall resistivity ρ of doped samples increases linearly from a negative to a positive magnetic field (B), demonstrating the normal Hall effect at room temperature. High temperature Hall concentration increases significantly with the gradual increase in both Mn and As doping due to more and more ionization of the deep donor level. High temperature activation energies of Mn doped β-FeSi2 are considerably greater than that of low temperature energies, which demonstrates clear evidence of the dual band model. From density functional theory calculations, the origin of the dual band model has been validated from the electronic structure of β-FeSi2. Both density of states and charge transfer to the system upon doping have been investigated through the density functional theory, which demonstrates the Mn and As doped systems to be p-type and n-type, respectively. Both Mn and As doped β-FeSi2 exhibit p-type and n-type conductivities for spin down and spin up channels, respectively, in the presence of an external magnetic field, which will encourage its applications in novel spintronic devices. In addition, a β-FeSi2 based homo-junction diode fabricated from the Mn and As doped β-FeSi2 exhibits a cut-in voltage of 0.82 V, a reverse breakdown voltage of −10 V, and an ideality factor of 3.87. Thus, doped β-FeSi2 will be very much useful for fabricating an efficient and cost-effective solar cell if fabricated physically. [ABSTRACT FROM AUTHOR]

The stable contact of heterogeneous interfaces and the substantial exposure of active sites are crucial for enhancing the photocatalytic performance of semiconductor catalysts. However, most reported two-dimensional (2D)/2D CsPbBr3 and BiOCl heterostructures are fabricated using electrostatic self-assembly methods, which exhibit significant deficiencies in precise interface quality control and effective active site exposure. In this study, we fabricate a zero-dimensional (0D)/2D CsPbBr3/BiOCl heterojunction via a two-step calcination method, achieving an efficient direct S-scheme configuration. Optimizing interfacial contact and band alignment between CsPbBr3 quantum dots and BiOCl nanosheets enhances cross-plane charge transfer, promoting superior charge separation. This 0D/2D CsPbBr3/BiOCl heterojunction exhibits enhanced carrier mobility and high conversion rates without cocatalysts or sacrificial agents. The mechanism underlying the accelerated S-scheme charge transfer is comprehensively elucidated through a combination of analytical techniques and density functional theory (DFT) calculations. This study offers a novel approach for managing charge carrier segregation and mobility in CO2 reduction photocatalysts. [ABSTRACT FROM AUTHOR]

Fluorescent molecular systems are important for various applications such as sensing of analytes, probes for biologically relevant processes and as optoelectronic materials. Achieving high fluorescence quantum yield across the spectrum of solvent polarity and in solid‐state is challenging in molecular materials. Herein, we present a strategy to achieve strongly fluorescent molecular materials based on weak intramolecular charge‐transfer (ICT) in a family of unsymmetrical donor‐thiazolo[5,4‐d]thiazole‐acceptor systems (both neutral and cationic). Detailed photophysical studies reveal that the delicate balance between the donor and acceptor result in high solution‐state fluorescence quantum yield (>80 %) in both polar protic and apolar solvents. Quantum chemical computations uncover a hitherto unappreciated insight that the extent of ICT is aptly represented by the change in Mulliken charges between the ground and excited state for different fragments rather than the classical approach of monitoring the change in dipole moment for the entire molecule. This insight rationalizes the observed photophysical properties and can have implications in the design of tuneable donor‐π‐acceptor systems. [ABSTRACT FROM AUTHOR]

Non-fullerene organic compounds are promising materials for advanced photovoltaic devices. The photovoltaic and electronic properties of the derivatives (TTBR and TTB1-TTB6) were determined by employing density functional theory (DFT) and time-dependent density functional theory (TD-DFT) analyses using the M06/6-311G(d,p) functional. To enhance the effectiveness of fullerene-free organic photovoltaic cells, modifications were applied to end-capped acceptors by using strong electron-withdrawing moieties. The structural tailoring showed a significant electronic impact for HOMO and LUMO for all chromophores, resulting in decreased band gaps (3.184–2.540 eV). Interestingly, all the designed derivatives exhibited broader absorption spectra in the range of 486.365–605.895 nm in dichloromethane solvent. Among all derivatives, TTB5 was observed to be the promising candidate because of its lowest energy gap (2.54 eV) and binding energy (0.494 eV) values, along with the bathochromic shift (605.895 nm). These chromophores having an A–π–A framework might be considered promising materials for efficient organic cells. [ABSTRACT FROM AUTHOR]

Si and its oxides have been extensively explored in theoretical research due to their technological importance. Simultaneously describing interatomic interactions within both Si and SiO2 without the use of ab initio methods is considered challenging, given the charge transfers involved. Herein, this challenge is overcome by developing a unified machine learning interatomic potentials describing the Si/SiO2/O system, based on the moment tensor potential (MTP) framework. This MTP is trained using a comprehensive database generated using density functional theory simulations, encompassing diverse crystal structures, point defects, extended defects, and disordered structure. Extensive testing of the MTP is performed, indicating it can describe static and dynamic features of very diverse Si, O, and SiO2 atomic structures with a degree of fidelity approaching that of DFT. [ABSTRACT FROM AUTHOR]

Air pollutants generated from volatile toxic chemicals pose significant public health concerns. Density functional theory (DFT) computations were used in this research to explore the efficiency and mechanism of harmful gas sensing over the reduced graphene oxide-polypyrrole (rGO-PPy) composite. Volatile molecule sensing was investigated for the NH3, H2CO, CH3OH, and C2H5OH gas molecules over three PPy orientations on the rGO substrate. Results showed that PPy orientation over rGO plays a crucial role in the sensing efficiency of the investigated gas molecules. The rGO-PPy composite, with PPy in a vertical orientation, demonstrated higher stability and enhanced sensing than other orientations. The results indicate that the strong hydrogen bonding of NH3 and CH3OH with both PPy and rGO significantly enhanced the sensing of these gas molecules on rGO by influencing the charge transfer with adsorption energy values of − 0.84 and − 0.92 eV, respectively. The lack of a direct hydrogen bonding with rGO and the weak hydrogen bonding with PPy caused a weak adsorption of H2CO and C2H5OH over rGO as indicated by the adsorption energy values of − 0.60 and − 0.78 eV, respectively. Selectivity analysis for the NH3 and C2H5OH gas molecules showed that NH3 can maintain hydrogen bonding with PPy in the presence of C2H5OH while C2H5OH cannot sustain this interaction. This study highlights the importance of the structural and electronic properties of the rGO-PPy composite in volatile pollutant sensing, providing insights for designing high-performance gas sensors. [ABSTRACT FROM AUTHOR]

We herein report a fundamental mechanistic investigation into photochemical metal‐nitrenoid generation and inner‐sphere transposition reactivity using organometallic photoprecursors. By designing Cp*Ir(hydroxamate)(Ar) complexes, we induced photo‐initiated ligand activation, allowing us to explore the amidative σ(Ir–aryl) migration reactivity. A combination of experimental mechanistic studies, femtosecond transient absorption spectroscopy, and density functional theory (DFT) calculations revealed that the metal‐to‐ligand charge transfer enables the σ(N−O) cleavage, followed by Ir‐acylnitrenoid generation. The final inner‐sphere σ(Ir–aryl) group migration results in a net amidative group transposition. [ABSTRACT FROM AUTHOR]

Hydrogen production through electrocatalytic water splitting or urea splitting has been considered one of the most fascinating methods to relieve the energy pressure. In this paper, the effects of Zr introduction on formation of NiFe 2 O 4 and catalytic activity are studied. Using oxygen evolution and urea oxidation as concerned reactions, the effects of different dosage on the catalytic performance of the materials were performed. It was found that the Zr–NiFe LDH@NiFe 2 O 4 /NF-1 material exhibited superior water oxidation properties (overpotential of 290 mV @100 mA cm−2). For urea oxidation reaction, the catalytic performance of this NiFe LDH material is better at low current density. However, at high current densities, this Zr–NiFe LDH@NiFe 2 O 4 /NF-1 electrode exhibits better electrochemistry performance. It is proved that the oxidation of water also contributes a part of the activity under large current. Density functional theory also suggests that the NiFe 2 O 4 material is favorable for water adsorption. This work will provide novel opinion for the development of environmentally friendly and low cost materials. It was found that the Zr–NiFe LDH@NiFe 2 O 4 /NF-1 material exhibited superior water oxidation properties (overpotential of 290 mV @100 mA cm−2). [Display omitted] • The formation of this NiFe LDH and NiFe 2 O 4 material can be induced by modulating the content of Zr. • The Zr–NiFe LDH@NiFe 2 O 4 presents a improved activity with small overpotentials of 290 mV for water oxidation. • The increase of performance is ascribed to the accelerated charge transfer and promoted electrolyte transfer. [ABSTRACT FROM AUTHOR]

For the first time the sensitive determination of carbendatim (CRB) is reported utilizing a well-designed sensing architecture based on vanadium diselenide-multiwalled carbon nanotube (VSMC). FTIR, XRD, FESEM, EDS, and EIS were employed to evaluate the sensor's structural integrity, and the results demonstrated the successful integration of nanomaterials, resulting in a robust and sensitive electrochemical sensor. Cyclic voltammetry (CV) and chronoamperometric (CA) investigations showed that the sensor best performed at pH 8.0 (BRB) with an excellent detection limit of 9.80 nM with a wide linear range of 0.1 to 10.0 µM. A more thermodynamically viable oxidation of CRB was observed at the VSMC/GCE, with a shift of 200 mV in peak potential towards the less positive side compared with the unmodified GCE. In addition, the sensor demonstrated facile heterogeneous electron transfer, favorable anti-fouling traits in the presence of a wide range of interferents, good stability, and reproducible analytical performance. Finally, the developed sensor was validated for real-time quantification of CRB from spiked water, food, and bio-samples, which depicted acceptable recoveries (98.6 to 101.5%) with RSD values between 0.35 and 2.23%. Further, to derive the possible sensing mechanism, the valence orbitals projected density of states (PDOS) for C, H, and N atoms of an isolated CRB molecule, VSe2 + CNT and VSe2 + CNT + CRB were calculated using density functional theory (DFT) calculations. The dominant charge transfer from the valence 2p-orbitals of the C and N atoms of CRB to CNT is responsible for the electrochemical sensing of CRB molecules. [ABSTRACT FROM AUTHOR]

The 203Pb and 212Pb lead radioisotopes are attracting growing interest as they can aid in the development of personalized, targeted radionuclide treatment for advanced and currently untreatable cancers. In the present study, the bonding interactions of Pb2+ with twelve macrocyclic ligands, having an octa and nona coordination, were assessed using Density Functional Theory (DFT) calculations. The molecular structures in an aqueous solution were computed utilizing the polarized continuum model. The preference for the twisted square antiprismatic (TSAP) structure was confirmed for ten out of the eleven cyclen-based complexes. The characteristics of the bonding were assessed using a Natural Energy Decomposition Analysis (NEDA). The analysis revealed a strong electrostatic character of the bonding in the complexes, with minor variations in electrical terms. The charge transfer (CT) had a comparable energetic contribution only in the case of neutral ligands, while in general, it showed notable variations regarding the various donor groups. Our data confirmed the general superiority of the carboxylate O and aromatic N donors. The combination of the selected efficient pendant arms pointed out the superiority of the acetate pendant arms and the lack of significant cooperation between the different pendant arms in the probed ligands. Altogether, the combination led only to a marginal enhancement in the total CTs in the complexes. [ABSTRACT FROM AUTHOR]

In the attempt to induce spin-polarized states in graphene (Gr), rare-earth deposition on Gr/Co(0001) has been demonstrated to be a successful strategy: the coupling of graphene with the cobalt substrate provides spin-polarized conical-shaped states (minicone) and the rare-earth deposition brings these states at the Fermi level. In this manuscript, we theoretically explore the feasibility of an analogue approach applied on Gr/Ni(111) doped with rare-earth ions by means of density functional theory calculations. Even if not well mentioned in the literature, this system owns a minicone, similar to the cobalt case. By testing different rare-earth ions, not only do we suggest which one can provide the required doping but we also explain the effect behind this proper charge transfer. [ABSTRACT FROM AUTHOR]

This study investigates how various functional groups affect the adsorption of carbon dioxide (CO2) in pillar[5]arenes (P[5]A) at the aim of enhancing CO2 capture in P[5]A for environmental applications. Density functional theory (DFT) and density‐functional‐based tight‐binding (DFTB) methods were employed to investigate the adsorption behavior of CO2 in pillar[5]arenes (P[5]A) with various functional groups including P[5]A with methyl (P[5]A‐OCH3), aldehyde (P[5]A‐OCOH) functional groups and pillar[5]quinone (P[5]Q). Self‐consistent charge DFTB calculations have been performed using the DFTB+ code, with dispersion corrections included for van der Waals interactions, to ensure accurate results at a lower computational cost. Bader charge analysis have been carried out with VASP code to understand the interaction mechanisms and charge transfer between P[5]A and CO2. The study demonstrates that changing the functional groups of P[5]A affects CO2 adsorption behavior. Specifically, CO2 adsorption is more favorable at the cavity site of P[5]A‐OCH3 compared to other functional groups, due to the combined effects of weak hydrogen bonds and π‐π interactions. The calculated results shows that the functionalization is one of the beneficial factors for CO2 capture in pillararenes, the adsorption energy and configuration of adsorbed CO2 at P[5]A are affected by both the polarization and geometry of the functional groups. Furthermore, the density of states (DOS) calculations confirm that CO2 is only physisorbed in P[5]A, ensuring the reusability of pillararenes after desorption. The findings of this study suggest that modifying the functional groups of pillararens is a promising strategy for developing high‐efficiency CO2 capture materials. [ABSTRACT FROM AUTHOR]

Directly electrochemical conversion of nitrate (NO3−) is an efficient and environmentally friendly technology for ammonia (NH3) production but is challenged by highly selective electrocatalysts. High‐entropy alloys (HEAs) with unique properties are attractive materials in catalysis, particularly for multi‐step reactions. Herein, we first reported the application of HEA (FeCoNiAlTi) for electrocatalytic NO3− reduction to NH3 (NRA). The bulk HEA is active for NRA but limited by the unsatisfied NH3 yield of 0.36 mg h−1 cm−2 and Faradaic efficiency (FE) of 82.66 %. Through an effective phase engineering strategy, uniform intermetallic nanoparticles are introduced on the bulk HEA to increase electrochemical active surface area and charge transfer efficiency. The resulting nanostructured HEA (n‐HEA) delivers enhanced electrochemical NRA performance in terms of NH3 yield (0.52 mg h−1 cm−2) and FE (95.23 %). Further experimental and theoretical investigations reveal that the multi‐active sites (Fe, Co, and Ni) dominated electrocatalysis for NRA over the n‐HEA. Notably, the typical Co sites exhibit the lowest energy barrier for NRA with *NH2 to *NH3as the rate‐determining step. [ABSTRACT FROM AUTHOR]

As a widely used support, TiO2 has often been combined with Pd to form highly sensitive gas-chromic materials. Herein, we prepared a series of Pd/TiO2 catalysts with different Pd content (from 0.1 to 5 wt.%) by the impregnation method for their utilization in fast room-temperature CO detection. The detection was simply based on visible color change when the Pd/TiO2 was exposed to CO. The sample with 1 wt.% Pd/TiO2 presented an excellent CO gasochromic character, associated with a maximum chromatic aberration value of 90 before and after CO exposure. Systematic catalyst characterizations of XPS, FT-IR, CO-TPD, and N2 adsorption–desorption and density functional theory calculations for the CO adsorption and charge transfer over the Pd and PdO surfaces were further carried out. It was found that the interaction between CO and the Pd surface was strong, associated with a large adsorption energy of −1.99 eV and charge transfer of 0.196 e. The color change was caused by a reduction in Pd2+ to metallic Pd0 over the Pd/TiO2 surface after CO exposure. [ABSTRACT FROM AUTHOR]

[Display omitted] Regulating interfacial active sites to improve peroxymonosulfate (PMS) activation efficiency is a hot topic in the heterogeneous catalysis field. In this study, we develop an inverted loading strategy to engineer asymmetric Mn–O V –Ce sites for PMS activation. Mn 3 O 4 @CeO 2 prepared by loading CeO 2 nanoparticles onto Mn 3 O 4 nanorods exhibits the highest catalytic activity and stability, which is due to the formation of more oxygen vacancies (O V) at the Mn–O V –Ce sites, and the surface CeO 2 layer effectively inhibits corrosion by preventing the loss of manganese ion active species into the solution. In situ characterizations and density functional theory (DFT) studies have revealed effective bimetallic redox cycles at asymmetric Mn–O V –Ce active sites, which promote surface charge transfer, enhance the adsorption reaction activity of active species toward pollutants, and favor PMS activation to generate (•OH, SO 4 •−, O 2 •− and 1O 2) active species. This study provides a brand-new perspective for engineering the interfacial behavior of PMS activation. [ABSTRACT FROM AUTHOR]

The structures, stability and electronic properties of the Ni-doped boron nitride tubular clusters (NiBm−1Nm), NH3 adsorption on the NiBm−1Nm (NH3NiBm−1Nm) and NH3 embedded into the NiBm−1Nm (NH3@NiBm−1Nm) (m = 48, 72 and 96) clusters have been investigated by using density functional theory. The results reveal that the diameters of the NiBm−1Nm clusters have almost no effect on the NH3 adsorption. The diameter of the NiB47N48 clusters is small enough to accommodate the NH3 molecules, and the appropriate diameter of the NiB71N72 clusters occurs to embed the NH3 molecules. The NH3 molecules prefer to adsorb on rather than embed into the NiBm−1Nm clusters. The charge transfer between the NH3 molecules and the NiBm−1Nm clusters is limit, in the range of 0.002–0.221 |e|. The adsorption between the NH3 molecules and the NiBm−1Nm clusters is chemical process. In a word, the curvature effects of the Ni-doped boron nitride nanotubes with various diameters on NH3 adsorption are restrict. [ABSTRACT FROM AUTHOR]

Context: Density functional theory (DFT) calculations on the ground and the first excited state are performed on the modified and unmodified 4-(methoxyphenyl acetonitrile) monomer (referred to as MPA). The modified monomer named MFA is obtained by Knoevenagel condensation of MPA with dimethylformamide dimethyl acetal (DMF-DMA). DFT computations show that the chemical grafting of the dimethylamino group onto the MPA unit induces a great change in the geometric, electronic, and optical properties. Going from MPA to MFA monomer, a great change in the frontier orbitals of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in the ground and the first excited state is observed. Consequently, a reduction in the energy gap HOMO–LUMO and an enhancement in the absorption and emission properties are observed under the chemical modification. The observed modifications in the electronics and optical properties are the result of the charge transfer appearing between the cyano (C≡N) acceptor group and the dimethylamino (DMF-DMA)-grafted group donor ring. Methods: Quantum chemical calculations were performed in the ground and the first excited state using the density functional theory (DFT), and it extends the time-dependent density functional theory (TD-DFT), implemented in the Gaussian 09 software package. The ground state is obtained by optimization of the studied molecular geometries by employing the DFT/M062X/6-31G(d,p) level of theory. The first excited state is obtained by re-optimization of the ground state geometries using the TD-DFT/M062X/6-31G(d,p) level of theory. The contour plots of the frontier orbitals and the molecular electrostatic potential (MEP) maps are obtained from the ground and the first excited state, optimized geometries, and drawn using Gaussview software. [ABSTRACT FROM AUTHOR]

The attractive physiochemical properties of two dimensional materials demonstrate them to be an emerging class of potential candidates for use in sensing devices. Studies have shown that silicene can act as an excellent chemical sensor; however, no work has been studied about silicene as a glucose sensor. In this paper, using density functional theory, the interaction of pristine silicene and transition metal‐doped (Ag, Au, Cu, Ni, and Pt) silicene is studied with glucose molecules. The calculated adsorption energy, energy gap, and charge transfer value confirmed that the nickel‐doped silicene sheet can be a good glucose sensor with high sensitivity, moderate recovery time, and high conductivity. Further, the electron localization function and the reduced density gradient confirm the physisorption between the glucose molecule and the metal‐doped silicene sheets. [ABSTRACT FROM AUTHOR]

A homologous series of 4,7‐bis(aryl) substituted benzothiadiazole (BTD) compounds, containing the helicenic derivatives bis([4]helicene), bis([5]helicene) and bis([6]helicene), have been prepared upon a double Suzuki coupling between 3,6‐bis(pinacolyl‐borane)‐BTD and the corresponding bromo‐aryl precursors. The single crystal X‐ray structure of the bis([4]helicene) compound shows the existence of both helicities (M) and (P) on the same molecule. All the compounds of the series are highly emissive in solution, with quantum yields of the emission ranging from 50 to 91 %. The enantiopure compounds (M,M) and (P,P) for the BTD‐bis([6]helicene) have been prepared from the corresponding enantiopure 2‐bromo‐[6]helicene precursors. Their chiroptical properties have been investigated in correlation with density functional theory (DFT) calculations, which allowed to confidently assign the absolute configuration of the helicene arms and to characterize the different electronic transitions, including the low energy charge transfer excitation from helicenes to BTD. The enantiomerically pure fluorophores (M,M)‐ and (P,P)‐BTD‐bis([6]helicene), which exist in solution as two main conformers, according to the DFT calculations, show CPL activity in solution, with glum factors of ≈1.7×10−3 at λem=525 nm, and also in the solid state, with glum factors of ≈1.2×10−3 in spite of the strong decrease of the quantum efficiency. [ABSTRACT FROM AUTHOR]

This article describes a density functional theory (DFT) study to explore a bio‐inspired NiFe complex known for its experimental activity in electro‐reducing CO2 to CH4 when adsorbed on graphite. The coordination properties of the complex are investigated in isolated form and when physisorbed on a graphene surface. A comparative analysis of DFT approaches for surface modeling is conducted, utilizing either a finite graphene flake or a periodic carbon surface. Results reveal that the finite model effectively preserves all crucial properties. By examining predicted structures arising from CO2 insertion within the mono‐reduced NiFe species, whether isolated or adsorbed on the graphene flake, a potential species for subsequent electro‐reduction steps is proposed. Notably, the DFT study highlights two positive effects of complex adsorption: facile electron transfers between graphene and the complex, finely regulated by the complex state, and a lowering of the thermodynamic demand for CO2 insertion. [ABSTRACT FROM AUTHOR]

It is important to tune the coordination configuration of dual‐atom catalyst (DAC), especially in the first coordination sphere, to render high intrinsic catalytic activities for oxygen reduction/evolution reactions (ORR/OER). Herein, a type of atomically dispersed and boron‐coordinated DAC structure, namely, FeN4B‐NiN4B dual sites, is reported. In this structure, the incorporation of boron into the first coordination sphere of FeN4/NiN4 atomic sites regulates its geometry and electronic structure by forming "Fe‐B‐N" and "Ni‐B‐N" bridges. The FeN4B‐NiN4B DAC exhibits much enhanced ORR and OER property compared to the FeN4‐NiN4 counterparts. Density functional theory calculations reveal that the boron‐induced charge transfer and asymmetric charge distributions of the central Fe/Ni atoms optimize the adsorption and desorption behavior of the ORR/OER intermediates and reduce the activation energy for the potential‐determining step. Zinc‐air batteries employing the FeN4B‐NiN4B cathode exhibit a high maximum power density (236.9 mW cm−2) and stable cyclability up to 1100 h. The result illustrates the pivotal role of the first‐coordination sphere of DACs in tuning the electrochemical energy conversion and storage activities. [ABSTRACT FROM AUTHOR]

In this study, nanocomposites of g‐C3N4/MN4 (where M is Mn, Fe and Co) have been designed using advanced density functional theory (DFT) calculations. A comprehensive analysis was conducted on the geometry, electronic, optical properties, work function, charge transfer interaction and adhesion energy of the g‐C3N4/MN4 heterostructures and concluded that g‐C3N4/FeN4 and g‐C3N4/CoN4 heterojunctions exhibit higher photocatalytic performance than individual units. The better photocatalytic activity can be attributed mainly by two facts; (i) the visible light absorption of both g‐C3N4/FeN4 and g‐C3N4/CoN4 interfaces are higher compared to its isolated analogs and (ii) a significant enhancement of band gap energy in g‐C3N4/FeN4 and g‐C3N4/CoN4 heterostructures limited the electron–hole recombination significantly. The potential of the g‐C3N4/MN4 heterojunctions as a photocatalyst for the water splitting reaction was assessed by examining its band alignment for water splitting reaction. Importantly, while the electronic and magnetic properties of MN4 systems were studied, this is the first example of inclusion of MN4 on graphene‐based material (g‐C3N4) for studying the photocatalytic activity. The state of the art DFT calculations emphasis that g‐C3N4/FeN4 and g‐C3N4/CoN4 heterojunctions are half metallic photocatalysts, which is limited till date. [ABSTRACT FROM AUTHOR]

The efficacy of aniline and carbazole‐based sensitizers used in dye‐sensitized solar cells (DSSCs) is correlated with the trends in density functional theory (DFT) based charge transfer (CT) and non‐linear optical (NLO) properties since both DSSC and NLO properties highly rely on CT properties. The aniline‐based donors showed a higher degree of planarity over carbazole‐based donor sensitizers. This improved planarity in aniline‐based sensitizers is attributed to efficient charge transfer and higher dipole moment. The efficient CT within the sensitizers is confirmed with bond‐length alternation (BLA), bond order alternation (BOA), and quinoid character (QC). A direct correlation of band‐gap (EG) with μ, ω, η, and Γ is witnessed. Time‐dependent DFT (TD‐DFT) results of vertical excitation demonstrated similar trends that are observed practically. Indeed, we observed a direct correlation between α and β and the experimentally observed DSSC efficiency. DFT and TD‐DFT methods, linear, employed for computing the CT and linear and DSSC properties as implemented in Gaussian 09. NLO properties were simulated through single‐point polar calculations. B3LYP and PBE1PBE functionals were used for geometry optimization. The linear and NLO properties were determined in various functionals, that is, global hybrid and range‐separated hybrid functionals. A polarizable continuum model (PCM) was used for solvation studies. To understand the realistic picture of the dye@TiO2 cluster, dye bound on TiO2 clusters were optimized using a LANL2DZ basis set specifically for the Ti atom. [ABSTRACT FROM AUTHOR]

To screen efficient organic dyes, six novel XY1b-based molecules are designed by modifying electron-assisted acceptors, and their electronic structure, optical properties and photovoltaic performances are evaluated in detail with density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations coupled with the incoherent charge transfer model. Results show that benzoselenadiazole (BSD) and diketopyrrolopyrrole (DPP) are two best electron-assisted acceptors and replacing benzothiadiazole (BTD) with the BSD/DPP unit can redshift the maximum absorption peak by 13/67 nm. According to our estimation, the overall photoelectric conversion efficiency (PCE) of XY1b is as high as 13.09% with a Jsc of 16.261 mA·cm−2, Voc of 1.047 V and FF of 0.769, in good agreement with its measured value of 11.8 ± 0.2% (Jsc = 15.26 ± 0.18 mA·cm−2, Voc = 1.01 ± 0.003 V and FF = 76.3 ± 0.2%), verifying that the scheme proposed by us is reliable. With the same procedure, the predicted PCE values for dyes 1, 2 and 5 reach up to 18.00%, 15.95% and 27.37% respectively, indicating that these three dyes are potential efficient sensitisers and are worthy of further study by experiments. [ABSTRACT FROM AUTHOR]

The development of stable and efficient electrocatalysts for overall freshwater/seawater water‐splitting has received significant attention. In this study, the fabrication and electrocatalytic properties of phosphorus‐enriched PtP2 dispersed on CoP (PtP2/CoP) for HER and OER in both alkaline fresh/seawater media are described. Physical characterization and density functional theory calculations reveal that strong electronic interfacial interactions between PtP2 and CoP optimized the reaction kinetics by regulating the adsorption/desorption of intermediates and the cleavage of reactants. Additionally, operando electrochemical impedance spectroscopy reveals that PtP2/CoP significantly decreased phase angle with increasing applied potential compared with CoP, demonstrating that the construction of heterostructure provides a faster charge transfer on the surface and in the inner layer. Notably, the catalyst only requires overpotentials of 101 and 298 mV to achieve a benchmark of 100 mA cm−2 in alkaline freshwater for HER and OER. Moreover, the prepared catalyst featured overpotentials of 108 and 330 mV in an alkaline seawater electrolyte. Furthermore, a stable and high‐efficiency water electrolysis operation can be achieved using PtP2/CoP as both the anode and cathode (1.63 V@100 mA cm−2) coupled with satisfactory durability. This finding provides a deeper comprehension of the interaction of Pt‐less compounds and matrix in electrocatalysis for bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]

Context: In the present work, we examined the sensing behavior of monolayer beta antimonide phosphorus (β-SbP) sheets towards toxic volatile organic compounds (VOCs) namely, 1,2-diethylbenzene and 2-ethyltoluene using density functional theory (DFT) method. At first, using cohesive energy structural stability of the monolayer β-SbP is confirmed. The calculated energy band gap value of monolayer β-SbP is 2.168 eV, which is a semiconductor. Furthermore, the adsorption properties of 1,2-diethylbenzene and 2-ethyltoluene on β-SbP are studied through key factors, such as adsorption energy, Mulliken charge transfer, and relative band gap variation. The adsorption energy clearly shows (− 0.335 to − 0.903 eV) that both 1,2-diethylbenzene and 2-ethyltoluene are physisorbed on β-SbP monolayer. Besides, Mulliken charge transfer falls in the range of − 0.465 to 0.933 e; this information clearly shows that the β-SbP monolayer is a potential candidate for sensing 1,2-diethylbenzene and 2-ethyltoluene molecules. Methods: The structural firmness including electronic and adsorption properties of 1,2-diethylbenzene and 2-ethyltoluene on β-SbP monolayer are investigated with the support of the DFT method. Particularly, the hybrid generalized gradient approximation (hybrid GGA) along with Beck's three-parameter + Lee–Yang–Parr (B3LYP) exchange–correlation functional is utilized for relaxing the β-SbP monolayer. In the present work, all calculations are performed using the Quantum Atomistic Tool Kit (ATK) simulation package. In the present work, we utilized β-SbP monolayer as a chief sensing element to detect 1,2-diethylbenzene and 2-ethyltoluene to safeguard humans from toxic environments. [ABSTRACT FROM AUTHOR]

Aqueous sodium (Na+) ion storage systems face challenges due to sluggish adsorption and diffusion of Na+ ions with larger size, hindering their potential for stationary applications. This issue is addressed by evolving the interfacial electronic coupling in atomically thin 2D WO3/WSe2 heterostructure for efficient Na+ ion storage. Density functional theory (DFT) analysis elucidates the superior charge storage capability for the WO3/WSe2 heterostructure facilitated by the charge transfer from the WO3 – WSe2 (002). The charge transfer from the W‐5d and O‐2p orbitals of WO3 to the valence W‐5d and Se‐4p orbitals of the WSe2 (002) surface boosts the electronic conductivity. As a result, the WO3/WSe2 electrode demonstrates exceptional Na+ ion storage, with a specific capacitance of 378.1 F g−1 at 1 A g−1, excellent rate capability, and long‐lasting cycling durability. The full cell comprising WO3/WSe2 as the negative and MnSe/MnSe2 as the positive electrode achieved a peak energy density of 82.1 Wh kg−1 at a power density of 1873.5 W kg−1, along with high rate capability and long‐cycle durability. Insights gained from this study pave the technique for the rational design and optimization of the interfacial electronic features in 2D heterostructures for next‐generation energy storage devices with enhanced performance and stability. [ABSTRACT FROM AUTHOR]

Low‐dimensional organic–inorganic hybrid perovskites (OIHPs) have attracted extensive attention due to their outstanding photoluminescence properties. However, the charge transfer between the organic A‐site and the inorganic framework is impeded, resulting in lower photoluminescence quantum yield (PLQY). Herein, m‐xylylenediamine (MXD) is incorporated into the perovskite, realizing the synthesis of a series of 0D perovskite‐like single crystals, i.e., (MXD)2PbX6 (X = Cl, Br, I). Density functional theory (DFT) calculations reveal the presence of effective hydrogen bonding between MXD and [PbX6]4−, which is enhanced through the controlled modification of halogen sites, enables the establishment of efficient charge transfer channels, and facilitates charge migration. Accordingly, (MXD)2PbCl6 achieves a PLQY as high as 55.9% at 460 nm, characterized by blue light emission and remarkable air stability. [ABSTRACT FROM AUTHOR]

It is crucial to identify an efficient system for the sensing of formaldehyde (FD). The feasibility of utilising a B3S monolayer (B3SML) detector of FD was evaluated by analysing the adsorption, optical properties, gas-sensing behaviour, and electronic properties of FD and other gas molecules on the B3SML under density functional theory (DFT). The pristine B3SML was found to have satisfactory sensing toward FD molecules. The analysis of the adsorption mechanisms, geometric systems, adsorption energy, electronic and optical properties, charge transfer, and electron density differences revealed that the B3SML could potentially serve as an FD detector. It can be said that the B3SML is a promising sensor for detecting FD molecules. The present study contributes to the existing knowledge of gas-surface interactions and helps develop 2D sensor structures to detect FD gas molecules. [ABSTRACT FROM AUTHOR]

Hole transport materials (HTMs) are indispensable for achieving high-performance perovskite optoelectronic devices. We have designed hole transport layer materials, and the geometries, electronic properties, excited state properties, and carrier mobilities of the promising experimental HTM molecule PCA-2 and designed molecules based on PCA-2 by substituting the core structures (named DMS, DMC, DMN and DMO) have been theoretically investigated by employing quantum chemistry methods. Our results show that all the HTMs exhibit excellent planarity and light absorption properties, which are beneficial for facilitating intramolecular charge transfer and enhancing device short-circuit current. The stability of all the studied HTMs was better than that of Spiro-OMeTAD. Additionally, the designed molecules exhibit good capability of hole injection, with DMC, DMN and DMO also displaying effective electron-blocking ability. The solubility of DMN surpasses that of all other molecules. Among the designed HTMs, the hole mobilities of all HTMs except for DMC, are improved compared with the experimental molecule PCA-2. Notably, DMN not only exhibits energy levels matching with perovskite but also has the largest hole mobility, which gives it the potential to be an ideal HTM. This comprehensive study will provide insights into charge transport materials for perovskite optoelectronic devices. [ABSTRACT FROM AUTHOR]

In this study, the effects of solvent environment changes, which are of critical importance in drug production processes, on the geometric structure and physicochemical parameters of the Hydroxychloroquine (HQC) molecule were investigated. For this purpose, optimized molecule structures were obtained using Density Functional Theory in vacuum and solvent environments. Based on the optimized structures, the molecule's thermochemical properties, atomic charges, and chemical reactivity data were calculated in vacuum and solvent environments. Moreover, the molecule's molecular electrostatic potential map and HOMOLUMO contour maps were drawn. Vibrational frequencies, intensities, and assignments in solvent environments were determined. The characteristics of the hydrogen bonding interactions established between solvent molecules and HQC were determined in detail. ADME, toxicity, and drug-likeness predictions of the molecule were made. The study results showed that while the structural, chemical, and physical properties of the HQC molecule were severely affected when transferred to the solvent environment, they were less affected by the changes between solvent environments. In addition, very strong h-bond interactions are established between the solvent molecules and HQC. [ABSTRACT FROM AUTHOR]

Incorporating two organic ligands with different functionalities into a titanium-oxo cluster entity simultaneously can endow the material with their respective properties and provide synergistic performance enhancement, which is of great significance for enriching the structure and properties of titanium-oxo clusters (TOCs). However, the synthesis of such TOCs is highly challenging. In this work, we successfully synthesized a TBC4A-functionalized TOC, [Ti2(TBC4A)2(MeO)2] (Ti2; MeOH = methanol, TBC4A = tert-butylcalix[4]arene). By adjusting the solvent system, we successfully introduced 1,10-phenanthroline (Phen) and prepared TBC4A and Phen co-protected [Ti2(TBC4A)2(Phen)2] (Ti2-Phen). Moreover, when Phen was replaced with bulky 4,7-diphenyl-1,10-phenanthroline (Bphen), [Ti2(TBC4A)2(Bphen)2] (Ti2-Bphen), which is isostructural with Ti2-Phen, was obtained, demonstrating the generality of the synthetic method. Remarkably, Ti2-Phen demonstrates good stability and stronger light absorption, as well as superior photoelectric performance compared to Ti2. Density functional theory (DFT) calculations reveal that there exists ligand-to-core charge transfer (LCCT) in Ti2, while an unusual ligand-to-ligand charge transfer (LLCT) is present in Ti2-Phen, accompanied by partial LCCT. Therefore, the superior light absorption and photoelectric properties of Ti2-Phen are attributed to the existence of the unusual LLCT phenomenon. This study not only deeply explores the influence of Phen on the performance of the material but also provides a reference for the preparation of materials with excellent photoelectric performance. [ABSTRACT FROM AUTHOR]

Charge transfer is a fundamental interface process that can be harnessed for light detection, photovoltaics, and photosynthesis. Recently, charge transfer was exploited in nanophotonics to alter plasmon polaritons by involving additional non-polaritonic materials to activate the charge transfer. Yet, direct charge transfer between polaritonic materials has not been demonstrated. We report the direct charge transfer in pure polaritonic van der Waals (vdW) heterostructures of α-MoO3/graphene. We extracted the Fermi energy of 0.6 eV for graphene by infrared nano-imaging of charge transfer hyperbolic polaritons in the vdW heterostructure. This unusually high Fermi energy is attributed to the charge transfer between graphene and α-MoO3. Moreover, we have observed charge transfer hyperbolic polaritons in multiple energy–momentum dispersion branches with a wavelength elongation of up to 150%. With the support from the density functional theory calculation, we find that the charge transfer between graphene and α-MoO3, absent in mechanically assembled vdW heterostructures, is attributed to the relatively pristine heterointerface preserved in the epitaxially grown vdW heterostructure. The direct charge transfer and charge transfer hyperbolic polaritons demonstrated in our work hold great promise for developing nano-optical circuits, computational devices, communication systems, and light and energy manipulation devices. [ABSTRACT FROM AUTHOR]

Binary antimonene-phosphorene, a novel 2D semiconductor material, shows potential applications in gas sensing due to its favorable properties. In this work, the sensing properties of binary antimonene-phosphorene nanoribbons by varying the phosphorus mole fraction for the adsorption of NO, CO, NO2, CO2, SO2, SO3, H2S, NH3, O2, and N2 gas molecules are theoretically investigated with first-principles method based on the density function theory. The adsorption distance, adsorption energy, charge transfer, work function, and recovery time of gas molecules adsorbed on the different substrates of phosphorus mole fraction are calculated and compared to evaluate the sensing performance of these structures. The results demonstrate that all the examined gas molecules form stable physisorption with binary nanoribbons (except O2 molecule). Through the analysis of adsorption energy and charge transfer, it can be seen that binary nanoribbons with mole fractions of 25 and 75% have higher selectivity and sensitivity to gas molecules. For example, the charge transfer results show that there is more charge transfer from SO3 (0.456 e) and O2 (0.4 e) gas molecules to 25 and 75% phosphorus substrates than other substrates of mole fraction, respectively. Moreover, for a better comparison, the I–V characteristics of different phosphorus mole fraction are calculated for SO3 and O2 gases. The calculated current–voltage curves confirm the charge transfer results. As a result, our theoretical studies show that binary nanoribbons with some mole fractions can offer promising platform for gas sensing applications. [ABSTRACT FROM AUTHOR]

Density functional theory was used in the present study to report and validate the 4-chloro-2-[(3,5-dichlorophenyl)carbamoyl]phenylbenzenesulfonate's (CPB) IR, Raman and SERS spectra. The molecular systems, CPB and CPB-Ag6 were initially optimized. Frontier molecular orbital study demonstrates that in CPB-Ag6 complex, charge transfer (CT) interaction occurs between Ag and molecule. CT interaction in the examined systems was further verified by the MEP surface. The CPB is chemisorbed on Ag6 with affinity and a tilted orientation through lone pair electrons of atoms, according to Raman and SERS spectral analyses. Additionally, there was good correlation between the theoretical and observed results. The current study thus lays the path for designing robust SERS active substrates that will be useful for creating biosensors related to the CPB molecule. [ABSTRACT FROM AUTHOR]

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe6− (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2‐TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti‐aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth‐doped semiconductor materials. [ABSTRACT FROM AUTHOR]

High operating temperatures and sluggish kinetics constrain the commercial application of magnesium-based hydrogen storage materials. To overcome these drawbacks, this work investigates heteroatom sulfur as a catalyst to improve the dehydrogenation of MgH 2 using density functional theory (DFT) and experimental validation. Heteroatom sulfur can influence the dehydrogenation of MgH 2 by modulating interfacial carbon-magnesium interactions and substituting surface hydrogen sites. In particular, DFT calculations reveal that sulfur functional groups facilitate charge transfer and significantly reduce the energy barrier of MgH 2 by 0.32 eV–1.59 eV. Substitution of sulfur atoms at surface hydrogen sites of MgH 2 notably improves dehydrogenation by weakening the Mg–H bond and enabling a sulfur-assisted two-step dehydrogenation mechanism. Experimental results further confirm these theoretical findings. The MgH 2 /900C–20SO 2 sample exhibits that the peak dehydrogenation temperature and the onset dehydrogenation temperature were 19.8 °C and 64 °C lower than that of pure MgH 2 , and a significant reduction in activation energy from 134.52 kJ mol−1 to 92.12 kJ mol−1. This research provides a comprehensive understanding of the catalytic effects of heteroatom sulfur on MgH 2 and offers crucial theoretical and practical insights for the development of more efficient magnesium-based hydrogen storage systems. [Display omitted] • The catalytic mechanism of heteroatom sulfur on the dehydrogenation of MgH 2 was investigated. • It was demonstrated that heteroatom sulfur can enhance the dehydrogenation of MgH 2. • Oxidized sulfur functional groups can weaken Mg–H bonds and facilitate charge transfer. • Some sulfur atoms form MgS in situ with Mg, triggering a two-step dehydrogenation. [ABSTRACT FROM AUTHOR]

Novel imidazopyridines hydrazine conjugates were designed and synthesized for their anti‐tubercular (anti‐TB) activity. A cytotoxicity assay was conducted with Vero cells to determine the safety profile of the most effective compounds. It was found that compound (IA3) (MIC=0.78 μM) and (IA8) (MIC=1.12 μM) were nearly 3.7 and 2.5 times more active than pyrazinamide. Based on Density functional theory (DFT), these molecules exhibited better charge transfer between molecular orbital's, which made them suitable for biological applications. Molecular docking on Mycobacterium tuberculosis InhA bound to NITD‐916 (PDB: 4R9S) revealed that compounds possessed greater binding affinity towards proteins. In addition, the most active anti‐TB compounds (IA3) and (IA8) exhibited high levels of interaction with the target protein and exceptional safety profile, suggesting they may prove to be effective leads for new drugs. [ABSTRACT FROM AUTHOR]

High-entropy oxides (HEOs) with a multi-cation structure have attracted significant attention in the fields of electrochemistry owing to their high entropy stability and cocktail effect. However, there has been very limited research on the use of HEO in the field of sensing. In this work, we utilized FeCoNiCrMn high-entropy alloys as the precursor to synthesize (FeCoNiCrMn)3O4 HEO and investigated their crystal structure, microscopic morphology, elemental valence state information, and gas sensing performance. The sensor exhibited decent response to NO2 at room temperature (RT) without any modification or sensitization methods. To verify the gas sensing mechanism, we simulated the interaction between five metal elements in HEO and the NO2 molecules by density functional theory, which reveals a crucial synergistic effect from the multiple cations to enhance the adsorption and charge transfer of NO2 molecules. This work explores the application potential of (FeCoNiCrMn)3O4 in low-power gas sensors and enriches the material selection for RT sensors. [ABSTRACT FROM AUTHOR]

Li−S batteries (LSBs) are considered as the attractive candidates for next‐generation high‐energy system due to their high energy and low cost. However, their practical application is hindered by several stubborn issues, including the poor electric conductivity of sulfur cathodes, the shuttle of lithium polysulfides (LiPSs) and the slow dynamics during charge/discharge cycles. Transitional iron (Fe)‐based compounds are regarded as effectively electrocatalysts for polysulfide conversion by accelerating the reaction kinetics and enhancing the electric conductivity and electron/charge transfer. In this study, we investigate the typical transition Fe‐based compounds (Fe3X, X=B, C, N), known for their high catalytic ability, analyze their roles as sulfur host for LSBs using density functional theory (DFT). Our finding reveals that Fe3C and Fe3B surfaces exhibit more Fe‐S bonds compared to Fe3N surface, which explains the different electrochemical behaviors observed during battery testing with sulfur cathodes. Additionally, Fe3N demonstrates greater structural stability and effective polysulfide adsorption according to DFT calculations, outperforming the other two compounds in these aspects. We believe that this theoretical investigation would guide the identification of highly efficient hosts for sulfur cathodes and open new avenues for sulfur host selection in LSBs. [ABSTRACT FROM AUTHOR]