Search

This research is focused on the sensor properties of pure and X-decorated (X = B , N, P and S) magnesium oxide (Mg 1 2 O 1 2 ) nanocages for melamine (C3H6N6) molecule detection using density functional theory (DFT) electronic structure approach. Comparative adsorption study was carried out on four distinct computational models of hybrid functionals: ω B97XD, PBE0-D3BJ, M062X-D3BJ and DSDPBEP86 with the double-hybrid (DSDPBEP86), being the superior model at the fifth rung of the Jacobi's ladder, was used as the reference. The atoms-in-molecule (AIM), alongside with the non-covalent interactions (NCIs) as visual extension had been utilized in the study of weak interactions and to affirm the degree of interactions between the clusters and the toxin. In all cases, this study suggests that the adsorption phenomena are best described as chemisorption due to the negative adsorption enthalpy observed. The mean absolute deviation (MAD) and root mean square deviation (RMSD) statistical approaches suggest the behavior of the possible adsorptions to be ranked as follows: PBE0-D3BJ (first rank), ω B97XD (second rank) and finally, M062X-D3BJ (third rank) with (MAD = 0. 7 8 4 6 , 0.7870 and 0.8402) and (RMSD = 0. 8 9 2 4 , 0.8946 and 0.9560), respectively. These results are consistent with those of the topological and the sensing parameters, hence, arriving at a conclusive scientific report that Mg 1 2 O 1 2 and Mg 1 2 PO 1 1 surfaces exhibit relatively better sensing performances for the trapping of melamine (MB). Investigation has been carried out on the sensor properties of pure and X-decorated (X = B, N, P and S) magnesium oxide (Mg12O12) nanocages for melamine (C3H6N6) molecule detection using density functional theory (DFT) approach. To get the best adsorption model, comparative adsorption study was carried out on four distinct computational models of hybrid functionals: ωB97XD, PBE0-D3BJ, M062X-D3BJ, and DSDPBEP86 with the double-hybrid (DSDPBEP86), being the superior model at the fifth rung of the Jacobi's ladder, used as the reference. Due to the negative adsorption enthalpy observed, the adsorption phenomena are best described as chemisorptions. [ABSTRACT FROM AUTHOR]

Owing to the fact that the detection limit of already existing sensor-devices is below 100% efficiency, the use of 3D nanomaterials as detectors and sensors for various pollutants has attracted interest from researchers in this field. Therefore, the sensing potentials of bare and the impact of Cu-group transition metal (Cu, Ag, Au)-functionalized silicon carbide nanotube (SiCNT) nanostructured surfaces were examined towards the efficient detection of NO 2 gas in the atmosphere. All computational calculations were carried out using the density functional theory (DFT) electronic structure method at the B3LYP-D3(BJ)/def2svp level of theory. The mechanistic results showed that the Cu-functionalized silicon carbide nanotube surface possesses the greatest adsorption energies of -3.780 and -2.925 eV, corresponding to the adsorption at the o-site and n-site, respectively. Furthermore, the lowest energy gap of 2.095 eV for the Cu-functionalized surface indicates that adsorption at the o-site is the most stable. The stability of both adsorption sites on the Cu-functionalized surface was attributed to the small ellipticity ( ε ) values obtained. Sensor mechanisms confirmed that among the surfaces, the Cu-functionalized surface exhibited the best sensing properties, including sensitivity, conductivity, and enhanced adsorption capacity. Hence, the Cu-functionalized SiCNT can be considered a promising choice as a gas sensor material., Competing Interests: All authors declare zero financial or inter-personal conflict of interest that could have influenced the research work or results reported in this research paper., (This journal is © The Royal Society of Chemistry.)

This study addresses the formidable persistence of tetracycline (TC) in the environment and its adverse impact on soil, water, and microbial ecosystems. To combat this issue, an innovative approach by varying polythiophene ((C 4 H 4 S) n ; n = 3, 5, 7, 9) units and the subsequent interaction with Ti-doped graphene/boron nitride (Ti@GP_BN) nanocomposites was applied as catalysts for investigating the molecular structure, adsorption, excitation analysis, and photodegradation mechanism of tetracycline within the framework of density functional theory (DFT) at the B3LYP-gd3bj/def2svp method. This study reveals a compelling correlation between the adsorption potential of the nanocomposites and their corresponding excitation behaviors, particularly notable in the fifth and seventh units of the polythiophene configuration. These units exhibit distinct excitation patterns, characterized by energy levels of 1.3406 and 924.81 nm wavelengths for the fifth unit and 1.3391 and 925.88 nm wavelengths for the seventh unit. Through exploring deeper, the examination of the exciton binding energy emerges as a pivotal factor, bolstering the outcomes derived from both UV-vis transition analysis and adsorption exploration. Notably, the calculated exciton binding energies of 0.120 and 0.103 eV for polythiophene units containing 5 and 7 segments, respectively, provide compelling confirmation of our findings. This convergence of data reinforces the integrity of our earlier analyses, enhancing our understanding of the intricate electronic and energetic interplay within these intricate systems. This study sheds light on the promising potential of the polythiophene/Ti-doped graphene/boron nitride nanocomposite as an efficient candidate for TC photodegradation, contributing to the advancement of sustainable environmental remediation strategies. This study was conducted theoretically; hence, experimental studies are needed to authenticate the use of the studied nanocomposites for degrading TC., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Diclofenac is one of the most frequently consumed over-the-counter anti-inflammatory agents globally, and several reports have confirmed its global ubiquity in several environmental compartments. Therefore, the need to develop more efficient monitoring/sensing devices with high detection limits is still needed. Herein, quantum mechanical simulations using density functional theory (DFT) computations have been utilized to evaluate the nanosensing efficacy and probe the applicability of Ga 12 As 12 nanostructure and its engineered derivatives (halogen encapsulation F, Br, Cl) as efficient adsorbent/sensor materials for diclofenac. Based on the DFT computations, it was observed that diclofenac preferred to interact with the adsorbent material by assuming a flat orientation on the surface while interacting via its hydrogen atoms with the As atoms at the corner of the GaAs cage forming a polar covalent As-H bond. The adsorption energies were observed to be in the range of -17.26 to -24.79 kcal/mol and therefore suggested favorable adsorption with the surface. Nonetheless, considerable deformation was observed for the Br-encapsulated derivative, and therefore, its adsorption energy was observed to be positive. Additionally, encapsulation of the GaAs nanoclusters with halogens (F and Cl) enhanced the sensing attributes by causing a decrease in the energy gap of the nanocluster. And therefore, this suggests the feasibility of the studied materials as potentiometric sensor materials. These findings could offer some implications for the potential application of GaAs and their halogen-encapsulated derivatives for electronic technological applications., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

A magnesium-decorated graphene quantum dot (C 24 H 12 -Mg) surface has been examined theoretically using density functional theory (DFT) computations at the ωB97XD/6-311++G(2p,2d) level of theory to determine its sensing capability toward XH 3 gases, where X = As, N and P, in four different phases: gas, benzene solvent, ethanol solvent and water. This research was carried out in different phases in order to predict the best possible phase for the adsorption of the toxic gases. Analysis of the electronic properties shows that in the different phases the energy gap follows the order NH 3 @C 24 H 12 -Mg < PH 3 @C 24 H 12 -Mg < AsH 3 @C 24 H 12 -Mg. The results obtained from the adsorption studies show that all the calculated adsorption energies are negative, indicating that the nature of the adsorption is chemisorption. The adsorption energies can be arranged in an increasing trend of NH 3 @C 24 H 12 -Mg < PH 3 @C 24 H 12 -Mg < AsH 3 @C 24 H 12 -Mg. The best adsorption performance was noted in the gas phase compared to the other studied counterparts. The interaction between the adsorbed gases and the surfaces shows a non-covalent interaction nature, as confirmed by the quantum theory of atoms-in-molecules (QTAIM) and non-covalent interactions (NCI) analysis. The overall results suggest that we can infer that the surface of the magnesium-decorated graphene quantum dot C 24 H 12 -Mg is more efficient for sensing the gas AsH 3 than PH 3 and NH 3 ., Competing Interests: All authors declare zero financial or inter-personal conflicts of interest that could have influenced the research work or results reported in this research paper., (This journal is © The Royal Society of Chemistry.)

The utilization of nanostructured materials for several biomedical applications has tremendously increased over the last few decades owing to their nanosizes, porosity, large surface area, sensitivity, and efficiency as drug delivery systems. Thus, the incorporation of functionalized and pristine nanostructures for cancer therapy offers substantial prospects to curb the persistent problems of ineffective drug administration and delivery to target sites. The potential of pristine (Ca 12 O 12 ) and formyl (-CHO)- and amino (-NH 2 )-functionalized (Ca 12 O 12 -CHO and Ca 12 O 12 -NH 2 ) derivatives as efficient nanocarriers for 5-fluorouracil (5FU) was studied at the B3LYP-GD3(BJ)/6-311++G(d,p) theoretical level in two electronic media (gas and solvent). To effectively account for all adsorption interactions of the drug on the investigated surfaces, electronic studies as well as topological analysis based on the quantum theory of atoms in molecules (QTAIM) and noncovalent interactions were exhaustively utilized. Interestingly, the obtained results divulged that the 5FU drug interacted favorably with both Ca 12 O 12 and its functionalized derivatives. The adsorption energies of pristine and functionalized nanostructures were calculated to be -133.4, -96.9, and -175.6 kcal/mol, respectively, for Ca 12 O 12 , Ca 12 O 12 -CHO, and Ca 12 O 12 -NH2. Also, both topological analysis and NBO stabilization analysis revealed the presence of interactions among O 3 -H 32 , O 27 -C 24 , O 10 -C 27 , and N 24 -H 32 atoms of the drug and the surface. However, 5FU@Ca 12 O 12 -CHO molecules portrayed the least adsorption energy due to considerable destabilization of the molecular complex as revealed by the computed deformation energy. Therefore, 5FU@Ca 12 O 12 and 5FU@Ca 12 O 12 -NH 2 acted as better nanovehicles for 5FU., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Toxicity in drug includes target toxicity, immune hypersensitivity and off target toxicity. Recently, advances in nanotechnology in the areas of drug delivery have help reduce toxicity and enhance drug solubility and deliver drugs to target sites more efficiently. In this study, we present a novel heteroatom functionalized quantum dot (QD-NBC and QD-NBS) as an effective drug delivery system for isoniazid. The said QD has been computationally modeled to assess its effectiveness in delivering isoniazid to desired target. Density functional theory (DFT) calculations were performed on the QD at the B3LYP/6-311+G(d, p) level to assess its stability through the natural bond orbital (NBO) calculations, and frontier molecular orbital (FMO) before and after interaction with isoniazid drug to understand any change in molecular behavior of the surface. Appropriate intermolecular interactions between the QD and the drug were computed through the Quantum theory of atoms in molecules (QTAIM) and Non-covalent interaction to assess the various binding mechanism and possible interactions resulting to the effective delivery of the drug target. To understand and accurately appraise the binding energy of adsorption, DFT calculations were performed with different functionals (B3LYP, CAM-B3LYP, PBEPBE, GD3BJ & WB97XD/6-311+G (d, p)). The results from DFT calculations point the functionalized QDs to be stable with appreciable energy gap suitable for delivery purposes. The adsorption energy of the drug target with the QD is in the range of -24.73 to 33.75 kcal/mol which indicates substantial interaction of the drug with the QD surface. This absorption energy is comparable with several reported literature and thus prompt the suitability of the surface for isoniazid delivery., Competing Interests: The authors declare no competing interests., (© 2022 The Authors.)

This study focused on the potential of aluminum nitride (Al 12 N 12 ) and aluminum phosphide (Al 12 P 12 ) nanomaterials as anode electrodes of lithium-ion (Li-ion), sodium-ion (Na-ion), and potassium-ion (K-ion) batteries as investigated via density functional theory (DFT) calculations at PBE0-D3, M062X-D3, and DSDPBEP86 as the reference method. The results show that the Li-ion battery has a higher cell voltage with a binding energy of -1.210 eV and higher reduction potential of -6.791 kcal/mol compared to the sodium and potassium ion batteries with binding energies of -0.749 and -0.935 eV and reduction potentials of -6.414 and -6.513 kcal/mol, respectively, using Al 12 N 12 material. However, in Al 12 P 12 , increases in the binding energy and reduction potential were observed in the K-ion battery with values -1.485 eV and -7.535 kcal/mol higher than the Li and Na ion batteries with binding energy and reduction potential -1.483, -1.311 eV and -7.071, -7.184 eV, respectively. Finally, Al 12 N 12 and Al 12 P 12 were both proposed as novel anode electrodes in Li-ion and K-ion batteries with the highest performances., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Upon various investigations conducted in search for a nanosensor material with the best sensing performance, the need to explore these materials cannot be overemphasized as materials associated with best sensing attributes are of vast interest to researchers. Hence, there is a need to investigate the adsorption performances of various metal-doped fullerene surfaces: C 59 Au, C 59 Hf, C 59 Hg, C 59 Ir, C 59 Os, C 59 Pt, C 59 Re, and C 59 W on thiourea [SC(NH 2 ) 2 ] molecule using first-principles density functional theory computation. Comparative adsorption study has been carried out on various adsorption models of four functionals, M06-2X, M062X-D3, PBE0-D3, and ωB97XD, and two double-hybrid (DH) functionals, DSDPBEP86 and PBE0DH, as reference at Gen/def2svp/LanL2DZ. The visual study of weak interactions such as quantum theory of atoms in molecule analysis and noncovalent interaction analysis has been invoked to ascertain these results, and hence we arrived at a conclusive scientific report. In all cases, the weak adsorption observed is best described as physisorption phenomena, and CH 4 N 2 S@C 59 Pt complex exhibits better sensing attributes than its studied counterparts in the interactions between thiourea molecule and transition metal-doped fullerene surfaces. Also, in the comparative adsorption study, DH density functionals show better performance in estimating the adsorption energies due to their reduced mean absolute deviation (MAD) and root-mean-square deviation (RMSD) values of (MAD = 1.0305, RMSD = 1.6277) and (MAD = 0.9965, RMSD = 1.6101) in DSDPBEP86 and PBE0DH, respectively., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

In recent times, nanomaterials have been applied for the detection and sensing of toxic gases in the environment owing to their large surface-to-volume ratio and efficiency. CO 2 is a toxic gas that is associated with causing global warming, while SO 2 and NO 2 are also characterized as nonbenign gases in the sense that when inhaled, they increase the rate of respiratory infections. Therefore, there is an explicit reason to develop efficient nanosensors for monitoring and sensing of these gases in the environment. Herein, we performed quantum chemical simulation on a Ca 12 O 12 nanocage as an efficient nanosensor for sensing and monitoring of these gases (CO 2 , SO 2 , NO 2 ) by employing high-level density functional theory modeling at the B3LYP-GD3(BJ)/6-311+G(d,p) level of theory. The results obtained from our studies revealed that the adsorption of CO 2 and SO 2 on the Ca 12 O 12 nanocage with adsorption energies of -2.01 and -5.85 eV, respectively, is chemisorption in nature, while that of NO 2 possessing an adsorption energy of -0.69 eV is related to physisorption. Moreover, frontier molecular orbital (FMO), global reactivity descriptors, and noncovalent interaction (NCI) analysis revealed that the adsorption of CO 2 and SO 2 on the Ca 12 O 12 nanocage is stable adsorption, while that of NO 2 is unstable adsorption. Thus, we can infer that the Ca 12 O 12 nanocage is more efficient as a nanosensor in sensing CO 2 and SO 2 gases than in sensing NO 2 gas., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

This theoretical study focuses on the adsorption, reactivity, topological analysis, and sensing behavior of metal-doped (K, Na, and Mg) aluminum nitride (Al 12 N 12 ) nanoclusters using the first-principle density functional theory (DFT). All quantum chemical reactivity, natural bond orbital (NBO), free energies (Δ G , Δ H ), and sensor parameters were investigated using the ωB97XD functional with the 6-311++G(d,p) basis set. The trapping of carboplatin (cbp) onto the surfaces of doped Al 12 N 12 was studied using four functionals PBE0-D3, M062X-D3, ωB97XD, and B3LYP-D3 at the 6-311++G(d,p) basis set. Overall, the substantial change in the energy gap of the surfaces after the adsorption process affects the work function, field emission, and the electrical conductivity of the doped clusters, hence making the studied surfaces a better sensor material for detecting carboplatin. Higher free energies of solvation were obtained in polar solvents compared to nonpolar solvents. Moreover, negative solvation energies and adsorption energies were obtained, which therefore shows that the engineered surfaces are highly efficient in trapping carboplatin. The relatively strong adsorption energies show that the mechanism of adsorption is by chemisorption, and K- and Na-doped metal clusters acted as better sensors for carboplatin. Also, the topological analysis in comparison to previous studies shows that the nanoclusters exhibited very high stability with regard to their relevant binding energies and hydrogen bond interactions.

The asymmetric unit of the title salt, C(8)H(22)N(4) (2+)·2C(7)H(5)O(3) (-), comprises half a 2,2'-(piperazine-1,4-di-yl)diethan-aminium dication plus a 2-hy-droxy-benzoate anion. In the crystal, the anions and cations are linked by N-H⋯O and O-H⋯O hydrogen bonds to form infinite two-dimensional networks parallel with the a unit-cell face. The conformation adopted by the cation in the crystal is very similar to that adopted by the same cation in the structures of the nitrate and tetra-hydrogen penta-borate salts.

The asymmetric unit of the title salt, C(6)H(20)N(4) (2+)·2I(-), comprises half a 3,6-diaza-octane-1,8-diaminium dication plus an I(-) anion. The dications are symmetrical and lie across crystallographic centres of inversion. In the crystal, the ions form a network involving mainly weak N-H⋯I inter-molecular inter-actions: two H atoms of the ammonium group form inter-actions with two I(-) anions and the H atom of the secondary amine forms a weak inter-action with a third I(-) cation. The third ammonium H atom is hydrogen bonded to a secondary amine of an adjacent cation. The backbone of the cation does not form a uniformly trans chain, but is 'kinked' [C-N-C-C torsion angle = 71.5 (2)°], probably to accommodate the direct hydrogen bond between the ammonium group and the secondary amine in an adjacent cation.

The asymmetric unit of the title salt C(8)H(22)N(4) (2+)·2C(7)H(5)O(2) (-), comprises two independent pairs of half a 2,2'-(piperazine-1,4-di-yl)diethanaminium dication plus a benzoate anion. The dications are symmetrical and lie across crystallographic centres of inversion. The crystal structure was refined as a two-component pseudo-merohedral twin using the twin law 001 0-10 100 [he domain fractions are 0.8645 (8) and 0.1355 (8)]. The anions and cations are linked by N-H⋯O hydrogen bonds and weak N-H⋯O inter-molecular inter-actions to form infinite two-dimensional networks parallel to [101]. The conformation adopted by the cation in the crystal structure is very similar to that adopted by the same cation in the structures of the 2-hy-droxy-benzoate [Cukrowski et al. (2012 ▶). Acta Cryst, E68, o2387], the nitrate and the tetra-hydrogen penta-borate salts.