Search

The search for low-diffusion barriers and high-capacity anode materials is considered a key step in boosting the efficiency of metal-ion batteries. Herein, we investigate the impact of a series of conducting polymers (CPs), namely, polyacetylene (PA), polypyrrole (PP), poly-p-phenylene (PPPh), and polythiophene (PT), on enhancing the material design and anodic performance of boron nitride nanosheet (BNNS)-based Li-ion and Na-ion batteries. For this purpose, first principle DFT simulations, utilizing both clustered and periodic models, are systematically performed to assess the stability of such nanostructures and their electronic behavior as potential anodic materials. It is revealed that frontier molecular orbitals calculated for BNNSs are stabilized upon association with the series of CPs, resulting in a reduction in the energy gaps of CP-BNNSs by nearly 50%, which in turn improves the charge transfer properties and cell reaction kinetics. A remarkable improvement in the cell voltage is predicted for PP and PT functionalized BNNSs, reaching approximately 3.5 V for Li+ and 3.0 V for Na+ ions. The outcome of the study emphasizes the influence of the size of metal ions, whether mono- or di-valent, and the nature of adsorbed conducting polymers. Manipulating the electronic features of boron nitride nanostructured surfaces through non-covalent functionalization with conducting polymers could pave the way for the design of highly efficient energy storage anodic CP-BNNS-based systems. [ABSTRACT FROM AUTHOR]

Two-dimensional covalent organic frameworks (2D-COFs) are a class of crystalline porous organic polymers, consisting of 2D-planar sheets stacked together perpendicularly via noncovalent forces. Since their discovery, 2D-COFs have attracted extensive attention for optoelectronic and adsorption applications. Owing to the layer stacking nature of 2D COFs, various new slipped structures that are energetically favourable can be designed. These interlayer slipped structures are actively responsible for tuning (mostly enhancing) the optoelectronic properties, thermal properties, and mechanical strength of 2D COFs. This review summarizes the effect of interlayer slipping on the energetic stability, electronic behaviour and gas adsorption properties of 2D layered COFs, which is explained through computational modelling simulations. Since computational modelling offers a deep insight into electronic behaviour at the atomic scale, which is potentially impossible through experimental techniques, the introduction and role of computational techniques in such studies have also been described. [ABSTRACT FROM AUTHOR]

The detection of toxic molecules has gained imperial attention to protect living organisms and their environment. The broadly explored sensor behaviour of triazine-based C3N4 reveals their ultra-high sensitivity towards numerous toxic molecules e.g., chemical welfare agents. However, another potential analogue of C3N4 composed of heptazine exhibits remarkable electrical and optical properties but has not been much explored in sensor technology, especially for toxic pollutants. Keeping this in mind, the sensing performance of heptazine-based g-C3N4 is explored for the detection of toxic amides by using First Principles calculations. In this context, acryloyl amide (C2H3CONH2), acryloyl chloride (C2H3COCl), fluoroacetic acid (C2H3FCOOH), flouroaceta amide (C2H2FONH2), flouroacetyl chloride (C2H2FOCl) are selected as toxic pollutants; herein, for the ease of understanding, these molecules are represented as AAM, ACl, FAAc, FAA, & FACl, respectively. The electrochemical sensitivity of g-C3N4 is determined via geometric, energetic, and electronic properties analysis, whereas the photochemical sensitivity is explored by UV–Vis absorption analysis based on TD-DFT calculations. The interaction energies of studied molecules on C3N4 range between − 9.09 and - 23.39 kcal/mol depending upon the type of interactions e.g., hydrogen bonding or dispersion, which are explained on the basis of Symmetry Adopted Perturbation Theory, Non-Covalent Interaction Index, and Quantum Theory of Atoms in Molecules analyses. The density of State analysis, Frontier Molecular Orbitals and NBO charge transfer characterized that the electronic behaviour of g-C3N4 can be an effective sensor material with a semiconducting nature and significant charge transfer. Lastly, UV–Vis absorption analysis confirms the photosensitivity of g-C3N4 upon interaction with toxic molecules. [ABSTRACT FROM AUTHOR]

In this study, for the first time, boron oxide nanoflake is analyzed as drug carrier for favipiravir using computational studies. The thermodynamic stability of the boron oxide and favipiravir justifies the strong interaction between both species. Four orientations are investigated for the interaction between the favipiravir and the B3O3 nanoflake. The Eint of the most stable orientation is −26.98 kcal/mol, whereas the counterpoise-corrected energy is −22.59 kcal/mol. Noncovalent interaction index (NCI) and quantum theory of atoms in molecules (QTAIM) analyses are performed to obtain insights about the behavior and the types of interactions that occur between B3O3 nanoflake and favipiravir. The results indicate the presence of hydrogen bonding between the hydrogen in the favipiravir and the oxygen in the B3O3 nanoflake in the most stable complex (FAV@B3O3-C1). The electronic properties are investigated through frontier molecular orbital analysis, dipole moments and chemical reactivity descriptors. These parameters showed the significant activity of B3O3 for favipiravir. NBO charge analysis transfer illustrated the charge transfer between the two species, and UV-VIS analysis confirmed the electronic excitation. Our work suggested a suitable drug carrier system for the antiviral drug favipiravir, which can be considered by the experimentalist for better drug delivery systems. [ABSTRACT FROM AUTHOR]

Herein, a series of D‐π‐A conjugated molecules based on donor N‐methyl‐4,5‐diazacarbazole with a variety of acceptor end caps are quantum chemically proposed with aim of rational design of novel organic materials applicable in organic solar cells (OSCs) by using ab initio density functional theory (DFT) calculations. Herein, the optoelectronic performance of tailored molecules was explored by substituting the bay annulated indigo dye acceptor unit with a variety of molecules including 4‐(5‐methyl‐thiophene‐2‐yl)benzothiadiazole; 1, 2‐(3‐methyl‐5‐methylene‐4‐oxothiazolidin‐2‐ylidene)‐malononitrile; 2, 3‐methyl‐5‐methylene‐2‐thioxothiazolodin‐4‐one; 3, 2‐methylenemalononitrile; 4, 2‐cynaoacryli‐caidmethylester; 5, those are linked through the thiophene bridge. The DFT results encompassed the significant variations of electronic behavior of newly designed molecules (M1‐M5) with respect to the reference molecule, especially in the case of 1, 2, and 3 substitution. The designed molecules exhibit excellent electron transition due to the increasing λmax toward the higher region. The outcomes of this study proposed the designed molecules as a possible choice in designing efficient optoelectronic materials for OSCs. From the future point of view, this finding suggests that the pre‐synthesis of such hypothetical molecules using quantum mechanics is an effective strategy for designing ideal candidates for solar cell applications. [ABSTRACT FROM AUTHOR]

A repeatedly infected person is one of the most important barriers to malaria disease eradication in the population. In this article, the effects of recurring malaria re-infection and decline in the spread dynamics of the disease are investigated through a supervised learning based neural networks model for the system of non-linear ordinary differential equations that explains the mathematical form of the malaria disease model which representing malaria disease spread, is divided into two types of systems: Autonomous and non-autonomous, furthermore, it involves the parameters of interest in terms of Susceptible people, Infectious people, Pseudo recovered people, recovered people prone to re-infection, Susceptible mosquito, Infectious mosquito. The purpose of this work is to discuss the dynamics of malaria spread where the problem is solved with the help of Levenberg-Marquardt artificial neural networks (LMANNs). Moreover, the malaria model reference datasets are created by using the strength of the Adams numerical method to utilize the capability and worth of the solver LMANNs for better prediction and analysis. The generated datasets are arbitrarily used in the Levenberg-Marquardt back-propagation for the testing, training, and validation process for the numerical treatment of the malaria model to update each cycle. On the basis of an evaluation of the accuracy achieved in terms of regression analysis, error histograms, mean square error based merit functions, where the reliable performance, convergence and effcacy of design LMANNs is endorsed through fitness plot, auto-correlation and training state. [ABSTRACT FROM AUTHOR]

Thermal management is essential for maintaining the optimal performance of electronic devices. Although covalent–organic frameworks (COFs) have emerged as a platform for gas and energy storage applications, their thermal transport properties are greatly understudied. Herein, we report the thermal conductivities of three benzobisoxazole (BBO)-linked COFs with nanpores ranging from 1.3 to 2.5 nm over a wide temperature range (80–300 K) using the longitudinal, steady-state heat-flow method. In doing so, thermal conductivity values as high as 0.677 W m–1 K–1 at 300 K were obtained, and no relationship between the thermal conductivity and pore size was observed. These results were supported by density functional theory calculations. The thermal conductivities of the BBO-COFs doped with poly-(3-hexylthiophene) were also investigated. The BBO-COFs could be useful as ultralow-k materials for thermal management applications. [ABSTRACT FROM AUTHOR]

Promising sensor applications of graphdiyne for various gases and toxic molecules have extensively been studied; however, similar studies for the detection of chemical warfare agents (CWA) are not reported. Here, we report the adsorption of Lewisites (L1, L2, and L3), on graphdiyne nanoflake (GDY) using density functional theory (DFT) ωB97XD/6‐31+G (d,p) method. Our results show that Lewisite molecules are preferably physiosorbed at the triangular portion of GDY nanoflake. In particular, the binding of L3 (3‐chlorovinyl arsine) on GDY nanoflake is thermodynamically favorable than L1 (1‐chlorovinylarsonous dichloride) and L2 (2‐chlorovinylarsonous chloride). Symmetry adopted perturbation theory (SAPT0) analysis reveals that the least contribution of repulsive exchange component is present in case of L2@GDY complex. Further, the smallest HOMO‐LUMO energy gap, appreciable charge transfer (NBO), and largest red shift in ultraviolet‐visible (UV‐Vis) spectrum are also in accord with the higher %sensitivity of graphdiyne toward L2. Quantum theory of atom in molecule (QTAIM) analysis is performed to get insight into the noncovalent interactions. Therefore, it is predicted that the sensitivity of GDY nanoflake is potentially high for Lewisite especially for L2. [ABSTRACT FROM AUTHOR]

Excess electron generation through doping with alkali and superalkali metals is well known to enhance NLO responses. On the contrary, superhalogen doping is an unexplored dimension. Herein, we report the first ever examples where superhalogen doping alone is introduced as a new and effective approach to impart large NLO responses. Density functional theory (DFT) calculations illustrate that superhalogen (BeF3 and BeCl3)-doped cyclic oligofurans (nCF) possess exceptionally high NLO responses (first hyperpolarizability (β0), hyper-Rayleigh scattering coefficient (βHRS), electro-optical Pockels effect (EOPE), second harmonic generation (SHG), and nonlinear refractive index (n2)), which are not trivial for organic compounds. Upon doping with superhalogens, the first hyperpolarizability (β0) of nCF increases to 3 × 105 a.u. in the BeF3@6CF complex, whereas the β0 values of the BeF3@5CF, BeCl3@5CF and BeCl3@6CF complexes are 6 × 104, 3 × 104 and 4 × 104 a.u., respectively. An enormously large third order nonlinear optical response coefficient with an electric field-induced second harmonic generation (ESHG) value of 2.1 × 109 a.u. is observed for the BeCl3@6CF complex. The remarkable NLO responses of the superhalogen-doped cyclic oligofuran complexes are due to the electron withdrawing nature of the halogen atoms, which are responsible for withdrawing electrons from the oxygen atoms of nCF to create poles. The significant hyperpolarizability (β0) of the BeF3@6CF complex is due to the most electronegative nature of fluorine. Furthermore, these results are rationalized through a two-level model. Bvec values are calculated for these complexes because they give more meaningful numbers from an experimental point of view. The stability of the complexes is judged through interaction energies, whereas electronic properties are calculated by chemical reactivity descriptors, the HOMO–LUMO gaps (Eg) and NBO charge transfer analysis. TD-DFT calculations reveal that the maximum absorbance for the BeF3@6CF complex is shifted to the longest wavelength. [ABSTRACT FROM AUTHOR]

Cyclic oligofurans containing five and six furan rings (5CF & 6CF) doped with superalkalis are presented here as a new type of NLO material. The OLi3@nCF, ONa3@nCF and OK3@nCF (n = 5 & 6) complexes are optimized at the M05-2X/6-31+G(d,p) level of theory. In these complexes, the superalkalis maintain their identity, and interact through the cavity of the cyclic oligofurans (nCF). Nonlinear optical properties are obtained through first hyperpolarizability (βo) of the complexes. The NLO response is rationalized on the basis of dipole moment (μo), energies of crucial excitation states (Eex) and vertical ionization energies (VIE). The highest hyperpolarizabilities (βo = 5 × 107 a.u. and βvec = 3 × 107 a.u.) are observed for OK3@nCF complexes along with the lowest EH–L, prominent NBO charge transfer, the highest dipole moment, and pronounced polarizability. The remarkable NLO response is attributed to the generation of excess electrons by superalkali doping. UV-Vis spectra are calculated to realize the transparency of these complexes in the UV-Vis region. The results suggest that higher NLO response is obtained when superalkalis are doped in higher oligofurans. [ABSTRACT FROM AUTHOR]

Linear conducting polymers are extensively studied as sensors for various analytes, whereas studies on cyclic analogues are limited. In this study, sensor applications of cyclic oligothiophenes (nCTs) have been explored by means of DFT (density functional theory) calculations. Three models, namely, five (5CT)-, six (6CT)- and seven (7CT)-membered cyclic oligothiophenes are evaluated against twelve different gaseous analytes. For optimization of geometries and interaction energies, the B3LYP method including Grimme's dispersion correction (B3LYP-D3) was applied with the 6-31++G(d,p) basis set. Chemical interactions of nCTs with NH3, CO, CO2, N2H4, HCN, H2O2, H2S, CH4, CH3OH, SO2, SO3 and H2O analytes are analyzed via interaction energies, Gibbs free energies, electronic properties and UV-Vis analysis. The interaction energies are quantitatively correlated with the volume of the cyclic oligothiophene (nCT). The electronic properties are calculated at the widely accepted B3LYP/6-31G(d) level of theory; however, the TD-B3LYP/6-31G(d) method is used for the UV-Vis analysis. Symmetry-adapted perturbation theory reveals that the 5CT system is highly sensitive towards analytes as compared to the 6CT and 7CT systems. This assumption is also strengthened by the HOMO–LUMO gaps and excited state properties. ESAPT, HOMO–LUMO gaps, NCI, and NBO charge transfer suggest that nCTs are highly sensitive towards SO3 followed by SO2. The density of state spectra shows the reasonable variation in the peaks of nCTs upon interaction with SO2 and SO3 analytes. The findings of this study suggest that cyclic oligothiophenes can effectively be used for the rational design of atmospheric sensors, which are superior to the conventional sensors. [ABSTRACT FROM AUTHOR]

Polypyrrole is experimentally reported as an excellent sensor for biological molecules including urea and uric acid. DFT calculations at M05-2X/6–31++G(d,p) are performed to gain theoretical insight into the sensing mechanism of polypyrrole for urea, uric acid, acetamide and sulfonamide. Geometry optimization and electronic property calculations have been performed on a series of oligopyrrole (1, 3, 5, 7 and 9) complexes, and the properties are extrapolated to infinite polymer through 2nd degree polynomial fit. Energy decomposition analyses (SAPT0) have been performed to demonstrate the contribution of electrostatic, induction, exchange and dispersion. The trend of SAPT0 interaction energies is very much comparable to that of binding energies. The noncovalent components of SAPT0 regularly increase with oligomer chain length; however, these components become almost constant after trimer for urea, acetamide, and sulfonamide. The increase in interaction and SAPT0 energies illustrate an increase in sensitivity of polypyrrole. Charge transfer and electronic properties also illustrate the high sensitivity of polypyrrole for uric acid. Energy difference between HOMO and LUMO orbitals of polypyrrole decreases upon doping with analytes. The decrease in the HOMO-LUMO gap shows an increase in the conductivity of polypyrrole. Our results indicate that polypyrrole has the highest sensing ability for uric acid, consistent with the experimental observations. [ABSTRACT FROM AUTHOR]

The desirability of the high nonlinear response of two-dimensional (2D) materials for electronics and optoelectronic devices drove us to investigate the nonlinear optical (NLO) behavior of alkali metal atom (AA) doped lithiated boron-containing hexahydroxy-triphenylene (LiBHHTP). In this context, the geometric, electronic, optical, and NLO properties are investigated. The doped AA atoms including Li, Na, and K preferably interact via the oxygen atoms of the LiBHHTP surface. The stability of the doped complexes is revealed by the interaction energies (E int), which are −22.90, −16.10, and −16.52 kcal/mol for Li@LiBHHTP, Na@LiBHHTP, and K@LiBHHTP complexes, respectively. The alterations in the electronic behavior of LiBHHTP are observed upon doping with alkali atoms via Frontier Molecular Orbital (FMO), Natural Bond Orbital (NBO), and the Density of State (DOS) analyses. The FMO analysis reveals that these complexes are electride in nature with absorption transparency in the UV–Vis range. Finally, the NLO behavior of designed complexes is evaluated through static and dynamic hyperpolarizabilities. Among reported complexes, K@LiBHHTP exhibits significantly large static hyperpolarizability (βₒ), 2.24 × 105 au. The dynamic NLO response of doped LiBHHTP complexes is also high, where the values are ranged in between 3.67 × 105 and 6.04 × 108 au at 1064 nm. This article not only highlights the effects of alkali atom doping on the NLO behavior of materials but also presents the first Lithiated boron-containing triphenylene as a next-generation optoelectronic material. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The drug carrier ability of B 3 O 3 toward Foscarnet is investigated via DFT. • The interaction is characterized by the geometric, energetic, electronic, and optical analyses. • Widely accepted ωB97XD/6-31+G(d,p) method of DFT is adopted for geometric analysis whereas for electronic properties B3LYP/6-31+G (d,p) method is used. • NCI and QTAIM analyses confirmed the nature of interactions. In this study, B 3 O 3 quantum dot is investigated via density functional theory (DFT) calculations as an antiviral drug carrier toward Foscarnet. Geometric analysis is carried out to find stable orientations of interaction between Foscarnet drug and the B 3 O 3 quantum dot. As a result, three stable orientations are proposed. The E int of the most stable orientation is –32.63 kcal/mol whereas the BSSE corrected energy is −26.98 kcal/mol. Noncovalent interaction index (NCI) and quantum theory of atoms in molecules (QTAIM) analyses are employed to understand the nature and the type of interactions taking place between drug and the B 3 O 3 quantum dot. Their results indicated the presence of hydrogen bonding in the most stable complex (orientation A). The HOMO-LUMO analysis is performed to study the electronic properties of the interacting moieties. The lowest E gap is observed in case of orientation A. The value of dipole moments and chemical descriptors showed the significant activity of B 3 O 3 quantum dot toward Foscarnet drug molecule. The overall findings from this study suggest the B 3 O 3 quantum dot as a potential drug carrier system for antiviral drugs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Drug carrying application of Triazine-based COF toward Tegafur is investigated via DFT calculations. • Boron-doping makes the Triazine-COF more applicable for Tegafur delivery. • Boron-doped Triazine-COF is more sensitive toward Tegafur. • Drug recovery time is better than previously reported carriers. The therapeutic potential of Triazines-based six-membered ring covalent organic framework (COF) and respective boron doped derivative toward anticancer drug i.e. , Tegafur (TG) is evaluated using the first principles DFT calculations. The geometric, energetic, and electronic properties of TG@Triazine and TG@TriazineB2 are computed to explore and compare the efficacy of selected COFs as drug carrier systems. The strength of the adsorption of tegafur onto the triazine-COFs is illustrated through the counterpoise corrected adsorption energies (Ecp). The computed Ecp of TG@Triazine and TG@TriazineB2 are −21.81 and −25.57 kcal/mol, which illustrate the physisorption of the drug on adsorbent. The nature of interactions i.e. , physisorption between tegafur and Triazine COFs is further illustrated via the noncovalent interaction index (NCI) plot and quantum theory of atom in molecules (QTAIM), which illustrated that the weak dispersion forces are present between the drug and COF adsorbents. In comparison, the adsorption strength is significantly high in boronated triazineB2 COF. The electronic properties, including HOMO-LUMO analysis and NBO charge transfer analysis, reveal the significant variation in the electronic behavior of triazine COF, upon doping with boron, the E g (HOMO-LUMO gap) of pristine Triazine (4.15 eV) reduced to 0.49 eV in TriazineB2 analogue. This significant decrease in the E g of Triazine on boron doping illustrates the shifting of the semiconducting behavior of pristine Triazine to the metallic nature of TriazineB2, thus the electron transportation becomes double the magnitude (0.018 |e|) on interaction with tegafur drug as compared to 0.07 |e| in TG@Triazine. Finally, the recovery time is computed to illustrate the time taken by the drug in detaching at the active site. With this study, it is confirmed that the triazine-COF can be a significant drug carrier, however, the doping of boron further enhances the therapeutic potential of the adsorbent. [ABSTRACT FROM AUTHOR]