This work shows an easy and eco-friendly methodology to obtain almost pristine anatase phase of TiO
by using furfural, a biomass-derived molecule, as a bio-template. The photocatalytic activity was ...studied following the degradation of methylene blue and phenol under artificial solar irradiation. Results were compared against those obtained on a commercial pristine anatase TiO
. The pseudo first-order, the second-order and the intraparticle diffusion kinetic models were verified. The textural and surface chemistry properties of the materials were correlated with the surface density of molecules adsorbed in equilibrium. The reaction-rate showed an almost perfect quadratic regression as a function of the surface density. Theoretical estimations of the density of states by DFT + U were performed showing that the total electron charge in the oxygen bonded to anatase TiO
increased due to carbon doping in agreement with the prediction of appearance of atomic orbitals 2p from carbon atom in the hybrid material. C-doping is responsible of the red-shift from 3.14 to 2.94 eV observed for a Ti
O
C super-cell than pristine anatase Ti
O
The increase in the activity of the C-doped TiO
photocatalyst was due to the decrease in the energy band-gap promoting a higher absorption of photons from the visible light.
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•N doping promoted the conversion of guaiacol and enhanced the formation of cyclohexanol.•Acidity modulation of Co-supported N-doped carbon catalyst enhanced C–O bond ...cleavage.•Catalyst formation mechanism was identified by DFT calculations.•N dopants collaborating alumina can improve the activity and stability of hybrid catalysts.
Bio-oil derived from biomass fast pyrolysis can be upgraded to gasoline and diesel alternatives by catalytic hydrodeoxygenation (HDO). Here, the novel nitrogen-doped carbon–alumina hybrid supported cobalt (Co/NCAn, n = 1, 2.5, 5) catalyst is established by a coagulation bath technique. The optimized Co/NCA2.5 catalyst presented 100 % conversion of guaiacol, high selectivity to cyclohexane (93.6 %), and extremely high deoxygenation degree (97.3 %), respectively. Therein, the formation of cyclohexanol was facilitated by stronger binding energy and greater charge transfer between Co and NC which was unraveled by density functional theory calculations. In addition, the appropriate amount of Lewis acid sites enhanced the cleavage of the C–O bond in cyclohexanol, finally resulting in a remarkable selectivity for cyclohexane. Finally, the Co/NCA2.5 catalyst also exhibited excellent selectivity (93.1 %) for high heating value hydrocarbon fuel in crude bio-oil HDO. This work provides a theoretical basis on N dopants collaborating alumina hybrid catalysts for efficient HDO reaction.
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•Spectroscopic results were compared with computed data.•Electronic properties of the title compound studied in various solvents.•Electron density map were computed using TD-DFT for ...different solvents.•Molecular docking studies confirm compound has a good antidepressant drug.
The biologically active compound 2,4,6-tri(propan-2-yl)benzenesulfonyl chloride has been investigated by utilizing both (FT-IR, Raman, UV–Vis, and proton and carbon NMR) experimental and (DFT and TD-DFT) theoretical techniques in this work. DFT has been used with B3LYP and basis set 6-311++ G(d,p) toward deriving molecular geometrical structure, vibrational frequencies. Frontier molecular orbital (FMO) and Ultra violet-Vis analysis of the headline compound with solvent effect have been investigated by TD-DFT/M062X method. The 1H, 13C nuclear magnetic resonance (NMR) chemical shift of the headline compound was calculated and these results compare to experimental data. The electrostatic potential with various solvent effects was portrayed to know the nucleophilic and electrophilic regions. Intra-molecular associates have been explained utilizing NHO, NLMO, and NBO analysis. The Mulliken charge analysis of the headline compound has also been investigated. Electron localization function (ELF) analysis gave details regarding the Pauli exchange repulsion effect in the electron of the molecule. The QSAR, Bioactive score prediction studies supported the developing biological activities of the headline compound. Finally, molecular docking is examined to detect the antidepressant activity of the heading compound.
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•Solvatochromic behavior of 3ABA in solvents analyzed using different approaches.•Hydrogen bond donating ability of solvents affecting the spectral behavior of 3ABA.•Excellent ...correlations obtained between calculated and experimental Stokes shifts.•Solute-solvent/solvent-solvent interactions play role in preferential solvation.•Transitions computed by the IEF-PCM model supports the experimental findings.
The present study elucidates the reinvestigation of the photophysical behavior of 3-aminobenzoic acid (3ABA) in solvents of different polarities using the steady-state spectroscopic techniques. Kamlet-Taft and Catalan solvatochromic models have been used to analyze the solvatochromic changes in neat solvents. The hydrogen bond donating ability of the solvent was found to be the main parameter affecting the spectral behavior of 3ABA. The solvatochromic characteristics of 3ABA have also been examined in binary solvent mixtures viz. acetonitrile (ACN)-methanol (MeOH) and benzene (BEN)-MeOH using the concept of preferential solvation. The preferential solvation of 3ABA shows unusual behavior for BEN-MeOH binary mixture and described unnoticed sigmoidal behavior in the ground state and synergistic impact in the excited state. Besides, the 3ABA was studied theoretically by quantum chemical calculations using (HF) Hartree-Fock and (DFT/B3LYP) density functional theories and its electronic absorption bands have been assigned by time-dependent density functional theory (TD-DFT). The effect of solvents on 3ABA was considered using a IEF-PCM-TDDFT (integral equation formalism of the polarizable continuum model- TDDFT) method. Thus, the theoretical results were found to be closer to the experimental results.
The interfacial instability between a thiophosphate solid electrolyte and oxide cathodes results in rapid capacity fade and has driven the need for cathode coatings. In this work, the stability, ...evolution, and performance of uncoated, Li2ZrO3‐coated, and Li3B11O18‐coated LiNi0.5Co0.2Mn0.3O2 cathodes are compared using first‐principles computations and electron microscopy characterization. Li3B11O18 is identified as a superior coating that exhibits excellent oxidation/chemical stability, leading to substantially improved performance over cells with Li2ZrO3‐coated or uncoated cathodes. The chemical and structural origin of the different performance is interpreted using different microscopy techniques which enable the direct observation of the phase decomposition of the Li2ZrO3 coating. It is observed that Li is already extracted from the Li2ZrO3 in the first charge, leading to the formation of ZrO2 nanocrystallites with loss of protection of the cathode. After 50 cycles separated (Co, Ni)‐sulfides and Mn‐sulfides can be observed within the Li2ZrO3‐coated material. This work illustrates the severity of the interfacial reactions between a thiophosphate electrolyte and oxide cathode and shows the importance of using coating materials that are absolutely stable at high voltage.
This work compares the stability, evolution, and performance of uncoated, Li2ZrO3‐coated, and Li3B11O18‐coated oxide cathodes using first‐principles computation and electron microscopy characterization. A lack of oxidation stability and O/S exchange are identified as critical failure modes of cathode coatings in thiophosphate‐based solid‐state batteries and strong oxygen bonding is suggested for creating highly stable cathode coatings.
We present a single synchrophasor estimation (SE) algorithm that is simultaneously compliant with both P and M phasor measurement unit (PMU) performance classes. The method, called ...iterative-interpolated discrete Fourier transform (i-IpDFT), iteratively estimates and compensates the effects of the spectral interference produced by both a generic interfering tone, harmonic or interharmonic, and the negative image of the fundamental tone. We define the three-point i-IpDFT technique for cosine and Hanning window functions and we propose a procedure to select the i-IpDFT parameters. We assess the performance of the i-IpDFT with respect to all the operating conditions defined in the IEEE Std. C37.118 for P- and M-class PMUs. We demonstrate that the proposed SE method is simultaneously compliant with all the accuracy requirements of both PMU performance classes.
A pyrazinamide-benzenesulfonohydrazide hybrid N'-(phenylsulfonyl)pyrazine-2-carbohydrazonamide (1), which was studied by physical measurements and computational tools, is reported. Compound 1 was ...synthesized using a metallic Na-assisted interaction of 2-cyanopyrazine with benzenesulfonylhydrazine in dry methanol. Our newly developed synthetic approach allowed to obtain the title compound witht the yield of 74%, which is more than twice higher in comparison to the previously reported synthesis using pyrazine-2-carbohydrazonamide and benzenesulfonyl chloride. Molecules of the title compound are linked via N–H⋯O, C–H⋯Ph, S=O⋯2-pyrazine and π⋯π interactions. As it was found by the Hirshfeld surface analysis, molecules of 1 interact through H⋯X (X = H, C, N and O) contacts. Electronic properties of 1 were revealed using the Density Functional Theory (DFT) computations. 1 was expected to be a fourth-class toxicity, and it does not penetrate the blood-brain barrier, while can potentially be absorbed by the gastrointestinal tract. It was predicted that compound 1, which demonstrated the strongest activity against PLpro, Nsp3_range 207–379 MES and Nsp16_SAM site, are of interest to suppress activity of the SARS-CoV-2 proteins. Although the Ki value is slightly higher, the ligand efficiency scores for complex PLpro–1 were found to be characteristic for a Hit.
We report on a novel pyrazinamide-benzenesulfonohydrazide hybrid N'-(phenylsulfonyl)pyrazine-2-carbohydrazonamide (1), which was studied by physical measurements and computational tools. Display omitted
•N'-(phenylsulfonyl)pyrazine-2-carbohydrazonamide (1) is reported.•Crystal structure of 1 was studied in detail.•Electronic properties of 1 were revealed using the DFT computations.•1 was probed in silico as a potential inhibitor of the SARS-CoV-2 proteins.
•Sulfamic acid-water clusters was calculated using DFT method.•Intermolecular interactions in Sulfamic acid-water clusters were discovered using AIM.•Sulfamic acid-water clusters was investigated by ...FTIR and XRD.•The introduction of water molecules into the cluster increases the intensity in the spectra FTIR and XRD.
Sulfamic acid is an essential reagent in organic chemistry. It is used in the synthesis of a large number of substances used in many areas of industry. This study aims to experimentally and theoretically study the nature and energy of interactions of intermolecular bonds between sulfamic acid and water molecules using DFT, NLO, AIM, FTIR and X-ray diffraction analysis. The geometry optimization of aqueous complexes of sulfamic acid with a content of water molecules from 1 to 8 was carried out in the gas phase using the DFT B3LYP/6-311 ++ G (d,p) and PBE-D3/6-311++G(d,p) methods. Thermodynamic studies and non-linear optical (NLO) propriety of the title compound have also been investigated. The nature of the molecular interactions between water and sulfamic acid via hydrogen bonds has been investigated using the Atoms in Molecules (AIM) method. X-ray diffraction analysis confirmed that sulfamic acid is monocrystalline, while sulfamic acid/water complexes are crystalline in nature. It is shown that with an increase in the number of water molecules in aqueous complexes of sulfamic acid, there is a uniform increase in the values of Heat Capacity, Entropy, Energy of complexes and Interaction energy. It is shown that all interactions of hydrogen bonds in all SAA- (H2O) 1-8 complexes have binding energies in the range from -1.31 to -154.91 kJ mol−1.
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A colorimetric and fluorescence turn-on cyanide probe, including coumarin–thiazole and imine (azomethine) group, has been designed and synthesized. It showed an immediate visible color change from ...yellow to deep red only in DMSO, and an appearance of strong yellow and green fluorescence when CN− was added to DMSO, and a mixture of DMSO:H2O (9:1), respectively. Thus, the sensor can be used to detect CN− in aqueous solution. The sensing mechanism of chemosensor 4 reactions with CN− ion was observed with the deprotonation and addition mechanisms at the same time. The mechanisms of reactions of chemosensor 4 with; CN−, F−, and AcO− were examined using 1H NMR spectroscopy, and were also theoretically supported by DFT and TD-DFT calculations. In addition, the metal complexes of chemosensor 4 with Pd(II) and Pt(II) were also synthesized and all the synthesized compounds were characterized using general spectroscopic methods (FTIR, 1H/13C NMR, and mass spectrometry), magnetic susceptibilities, and conductivity measurements. Also, the molecular structure of 4 was determined using single crystal X-ray analysis.
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Two series of bulky alkaline earth (Ae) metal amide complexes have been prepared: AeN(TRIP)22 (1‐Ae) and AeN(TRIP)(DIPP)2 (2‐Ae) (Ae=Mg, Ca, Sr, Ba; TRIP=SiiPr3, DIPP=2,6‐diisopropylphenyl). While ...monomeric 1‐Ca was already known, the new complexes have been structurally characterized. Monomers 1‐Ae are highly linear while the monomers 2‐Ae are slightly bent. The bulkier amide complexes 1‐Ae are by far the most active catalysts in alkene hydrogenation with activities increasing from Mg to Ba. Catalyst 1‐Ba can reduce internal alkenes like cyclohexene or 3‐hexene and highly challenging substrates like 1‐Me‐cyclohexene or tetraphenylethylene. It is also active in arene hydrogenation reducing anthracene and naphthalene (even when substituted with an alkyl) as well as biphenyl. Benzene could be reduced to cyclohexane but full conversion was not reached. The first step in catalytic hydrogenation is formation of an (amide)AeH species, which can form larger aggregates. Increasing the bulk of the amide ligand decreases aggregate size but it is unclear what the true catalyst(s) is (are). DFT calculations suggest that amide bulk also has a noticeable influence on the thermodynamics for formation of the (amide)AeH species. Complex 1‐Ba is currently the most powerful Ae metal hydrogenation catalyst. Due to tremendously increased activities in comparison to those of previously reported catalysts, the substrate scope in hydrogenation catalysis could be extended to challenging multi‐substituted unactivated alkenes and even to arenes among which benzene.
Bulk=Hulk: Superbulky alkaline earth metal amide complexes were found to be extremely active catalysts for alkene hydrogenation, clearly extending the substrate scope. Even various arenes, including benzene, can be reduced under relatively mild conditions.
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