Detection of trace level of hazardous phosgene gas on antimonene nanotube based on first-principles method

Effect of glycerin on the physical properties of polyvinyl alcohol/sodium alginate blend

Because of the abundance of sodium resources, sodium-ion batteries (NIBs) offer a promising alternative electrochemical energy storage solution. One of the current roadblocks to the development of NIBs technology is a lack of electrode materials capable of reversibly storing/releasing sodium ions for a sufficiently long time. Thus, this work aims to study, theoretically, the effect of glycerin incorporation on polyvinyl alcohol (PVA)/sodium alginate (Na Alg) blend as electrode materials for NIBs. The electronic, thermal, and quantitative structure-activity relationship (QSAR) descriptors of polymer electrolytes based on a blend of PVA and Na Alg and glycerin are the main topics of this work. These properties are examined here using semi-empirical methods and the density functional theory (DFT). Bandgap energy (Eg) is examined because the structural analysis reveals details regarding the interactions between PVA/Na Alg and glycerin. The findings indicate that the addition of glycerin caused the Eg value to drop to 0.2814 eV. The molecular electrostatic potential surface, or MESP, shows the electron-rich and deficit regions throughout the electrolyte system as well as the distribution of molecular charges. Thermal parameters that are studied include enthalpy (H), entropy (ΔS), heat capacity (Cp), Gibbs' free energy (G), and heat of formation. Additionally, the study examines several QSAR descriptors, such as total dipole moment (TDM), total energy (E), ionization potential (IP), Log P, and Polarizability. The results show that H, ΔS, Cp, G, and TDM increased with increasing temperature and glycerin content. Meanwhile, heat of formation, IP, and E decreased, improving reactivity and polarizability. Additionally, the cell voltage increased to 2.488 V due to glycerin addition. The overall DFT and PM6 calculations of cost-effective PVA/Na Alg based glycerin electrolytes indicate that they can partially replace lithium-ion batteries due to their multifunctionality, but requires further improvement and investigations.

Two-dimensional antimonene as a potential candidate for dioxin capture

Among the serious environmental problems that attracted much attention from the broader public is the high toxicity of dioxins. Considerable efforts have been made to develop techniques and materials that could help in their efficient removal from the environment. Due to its high specific surface area, numerous active sites, and outstanding structural and electronic properties, antimonene is considered for a variety of potential applications in different fields such as energy storage, electrocatalysis, and biomedicine. The present study adds to this portfolio by suggesting antimonene as a promising candidate for dioxin capture. Using density functional theory calculations, we studied the adsorption of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on pristine as well as Ca-, Ti-, and Ni-doped antimonene. Three spatial configurations of the adsorption of TCDD on antimonene were analyzed. The results obtained from the calculation of adsorption energies, charge transfer, and densities of states provide evidence that antimonene outperforms other nanomaterials that have been previously suggested for dioxin capture applications. Therefore, we propose these substrates (i.e., pristine and doped antimonene) as potential capture agents for removing such toxic organic pollutants.

Mechanical characteristics and failure behavior of puckered and buckled allotropes of antimonene nanotubes: a molecular dynamics study

In recent years, antimonene nanotubes have attracted considerable interest for diverse applications owing to their promising physical properties. In this study, classical molecular dynamics simulations with Stillinger-Weber potential were carried out to explore the fundamental mechanical characteristics of two stable allotropes of antimonene nanotubes (SbNTs), namely puckered (α-) and buckled (β-) nanotubes. Mechanical properties and deformation mechanisms of antimonene nanotubes, including ultimate tensile strength, fracture strain, and Young's modulus, were thoroughly examined by considering chirality, diameter, temperature, and strain rate variables. Numerical simulations revealed that all SbNT specimens examined in this study exhibit brittle failures with a complete loss of load-bearing capability following the ultimate stress level. The brittle nature of the SbNTs with varied diameters remained unchanged under different temperatures and loading-rate conditions. Owing to their distinct crystal structure in the armchair and zigzag directions, α-SbNTs present a distinctive anisotropic behavior compared to β-SbNTs. While the variation of the elastic modulus with temperature is not notable, the tensile strength and fracture strain of SbNTs deteriorated considerably at high temperatures. Furthermore, it was observed that the effects of diameter and temperature on zigzag α-SbNT are more pronounced due to its lower stability. Altogether, this study presents a comprehensive examination of the mechanical characteristics of the two stable antimonene allotropes and provides useful information for their potential utilizations in a wide range of applications.

Modeling of magnesium-decorated graphene quantum dot nanostructure for trapping AsH3, PH3 and NH3 gases

A magnesium-decorated graphene quantum dot (C₂₄H₁₂-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 XH₃ 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 NH₃@C₂₄H₁₂-Mg < PH₃@C₂₄H₁₂-Mg < AsH₃@C₂₄H₁₂-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 NH₃@C₂₄H₁₂-Mg < PH₃@C₂₄H₁₂-Mg < AsH₃@C₂₄H₁₂-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 C₂₄H₁₂-Mg is more efficient for sensing the gas AsH₃ than PH₃ and NH₃.

The elemental 2D materials beyond graphene potentially used as hazardous gas sensors for environmental protection

The intrinsic and electronic properties of elemental two-dimensional (2D) materials beyond graphene are first introduced in this review. Then the studies concerning the application of gas sensing using these 2D materials are comprehensively reviewed. On the whole, the carbon-, nitrogen-, and sulfur-based gases could be effectively detected by using most of them. For the sensing of organic vapors, the borophene, phosphorene, and arsenene may perform it well. Moreover, the G-series nerve agents might be efficiently monitored by the bismuthene. So far, there is still challenge on the material preparation due to the instability of these 2D materials under atmosphere. The synthesis or growth of materials integrated with the technique of surface protection should be associated with the device fabrication to establish a complete process for particular application. This review provides a complete and methodical guideline for scientists to further research and develop the hazardous gas sensors of these 2D materials in order to achieve the purpose of environmental protection.

A computational study on the BN-yne sheet application in the Na-ion batteries

Although Li-ion batteries are extensively applied, short lifetime, high cost, and safety problems limit their application. Na-ion batteries (NIB) might be an alternative to the Li-ion owing to wide availability, low cost, and nontoxicity of Na. Here, we performed density functional theory calculations to investigate the possible application of a graphyne-like BN layer (BN-yne) in the anode of NIBs. The adsorption energies of Na and Na⁺ on the BN-yne are predicted to be -15.3 and -54.6 kcal/mol, respectively. It was found that the maximum barrier energy for migration of Na atom and Na⁺ ion through BN-yne surface is about 20.2 and 16.5 kcal/mol, respectively. The calculated cell voltage for the BN-yne are predicted to be and 1.70 V. Using an electric field of -0.02 a. u. much more strengthens the interaction of Na⁺ with the BN-yne compared to the Na atom, increasing the cell voltage of NIB to 2.10 eV. We showed that a high Na storage capacity (Na₄B₂N₂), high cell voltage and diffusion ability of BN-yne make it a promising candidate for the NIB anode material.

Exploring adsorption behavior of ethylene dichloride and dibromide vapors on blue phosphorene nanosheets: A first-principles acumens

The interrelation of toxic vapors ethylene dichloride (EDC) and ethylene dibromide (EDB) with the sensory base material blue phosphorene nanosheet (BLPNS) is studied using ab-initio method. The formational stability of BLPNS is ensured by the negative value of formation energy. Prior to the adsorption studies, we calculated the formation energy of BLPNS to ensure its stability, which is calculated to be -5.194eV/atom and found stable. The main motive behind the present work is to detect these toxic vapors using BLPNS. The intercommunication between the targeted vapors and the base material has been analyzed using the aid of adsorption energy, Bader charge transfer, energy band gap, and variation of band gap along with energy bands and DOS spectrum. The energy gap of isolated BLPNS is observed to be 1.621eV. However, the adsorption of EDC and EDB modulates the energy gap of BLPNS. The nature of assimilation is noticed to be of physisorption, which facilitates desorption of EDC and EDB molecules much easier. The successful outcome of the present research validates that BLPNS can be deployed as a prominent sensor for detection of EDC and EDB effectively.

Theoretical prediction of 2D XI2 (X=Si, Ge, Sn, Pb) monolayers by density functional theory

Two dimensional monolayer semiconductors play an important role in designing opto-electronic devices for applications. In this paper, through the properties of the density functional theory, by running a series of first principles computations, the stability and the electronic properties of XI₂ (X = Si, Ge, Sn, Pb) monolayer structures is investigated. Our calculations indicate that 2D SiI₂, GeI₂, SnI₂, and PbI₂ monolayer materials show good stabilities. Accessing on their electronic properties indicates that they have semiconducting nature with strain tunable indirect band gaps of 2.38, 2.80, 2.72, and 3.23 eV respectively which are obtained by functional (HSE06) level of theory. The obtained electronic properties can be effectively tuned by strain effects suggests the predicted 2D monolayer materials for application in new opto-electronic devices.

CrI3-WTe2: A Novel Two-Dimensional Heterostructure as Multisensor for BrF3 and COCL2 Toxic Gases

A new multisensor (i.e. resistive and magnetic) CrI₃-WTe₂ heterostructure (HS) to detect the toxic gases BrF₃ and COCl₂ (Phosgene) has been theoretically studied in our present investigation. The HS has demonstrated sensitivity towards both the gases by varying its electronic and magnetic properties when gas molecule interacts with the HS. Fast recovery time (<0.14 fs) under UV radiation has been observed. We have considered two configurations of BrF₃ adsorbed HS; (1) when F ion interacts with HS (C1) and (2) when Br ion interacts with HS (C2). In C1 case the adsorption energy E_ad is observed to be −0.66 eV while in C2 it is −0.95 eV. On the other hand in case of COCl₂E_ad is found to be −0.42 eV. Magnetic moments of atoms are also found to vary upon gas adsorption indicates the suitability of the HS as a magnetic gas sensor. Our observations suggest the suitability of CrI₃-WTe₂ HS to respond detection of the toxic gases like BrF₃ and COCl₂.

A potent colorimetric and fluorogenic phosgene probe based on dual photophysical processes: PET attenuation and ICT reversal

An easily obtainable pyrene benzothiazole platform for the selective detection of hazardous analyte phosgene simply via quaternization of the benzothiazole N atom, which precludes any ring opening or closure.