Study on the adsorption properties of O3, SO2, and SO3 on B-doped graphene using DFT calculations

Modeling of Si-B-N Sheets and Derivatives as a Potential Sorbent Material for the Adsorption of Li+ Ion and CO2 Gas Molecule

In the present exploration, a few Si-B-N derivatives are derived to adsorb Li ions and CO₂ gas molecules for the potential application of metal-air batteries. The newly derived structure's bond lengths are as follows: Si=Si, 2.2 Å; Si-B, 1.9 Å; Si-N, 1.7 Å; and B-N, 1.4 Å, consistent with the experimental results of relevant structures. The stability of the newly derived structures is examined by the atom-centered density propagation study by varying the temperature from 270 to 400 K, and no structural variations are observed throughout the dynamics. Li adsorption on the Si₄B₂ ring has the maximum binding energy of -3.9 eV, and the result is consistent with the previous results. The rings with the 2:1 silicon-boron ratio provide strong adsorption for Li atoms. The calculated maximum electromotive force of the newly derived sheets is 0.56 V with the maximum theoretical density of 783 Wh/kg. Similarly, the maximum adsorption of CO₂ on the sheet is -0.106 eV, which is considerably higher than that on graphene and its derivatives. CO₂ adsorption has been carried out in the presence of water molecules to investigate the change in CO₂ adsorption with the moisture (water) content, and the results show no significant change in the adsorption of CO₂ with moisture. However, water has a strong interaction with the maximum interaction energy of -0.72 eV. Further, to explore the potential ability of the sheets, each sheet's edges are examined as hydrogen storage expedient and the surface as an artificial photosynthesis platform. The Si₄B₂ ring is more favorable for the adsorption of H atom with the chemisorption of -7.138 eV. Similarly, all of the major UV-absorption spectral peaks fall between 450 and 800 nm, which shows that the sheet can be used as an artificial photosynthesis platform.

DFT study of CO adsorption on nitrogen/boron doped-graphene for sensor applications

We have performed a Density Functional study of the CO adsorption in B-doped, N-doped and BN-co-doped graphene considering a coronene based model in order to estimate the applications of this systems as CO-sensor. Different monosubstituted, disubstituted and trisubstituted alternatives of combining these two heteroatoms in a substitutional chemical doping and the influence of the relative positions of the heteroatoms are analyzed. In this study, the stability selectivity for CO adsorption and the change in the electric properties for the presence of this molecule, have been evaluated through the calculation of binding energy, CO-adsorption's energy and the gap HOMO-LUMO change due to CO adsorption. The results indicated that, even though all the configurations were stables and was confirmed a CO physical adsorption in all of them, the relative positions of Nitrogen and Boron gave different stabilities and different responses to the CO adsorption. Since monosubstituted Boron-coronene was the second in stability respect to pristine coronene, showed the highest CO adsorption energy and was also the second highest ∆(∆_HOMO-LUMO) value, this structure could be potentially a good CO-sensor.

Interactions of graphene derivatives with glutamate-neurotransmitter: A parallel first principles - Docking investigation

Glutamate plays an important role in excitatory neurotransmission, learning, and memory processes, and under pathological conditions it is directly associated with several chronic neurological disorders, such as depression, epilepsy, schizophrenia, and Parkinson's. Therefore, the detection and quantification of Glutamate is important for the rapid diagnosis of these diseases. Using first principles and molecular docking simulations we have evaluated the energetic, structural, and binding properties of graphene derivatives, such as pristine graphene (pristine-Gr) and oxidized graphene with carboxylic (Gr-COOH), carbonyl (Gr-COH), hydroxyl (Gr-OH), and epoxy (-O-) groups interacting with the glutamate neurotransmitter. The calculated binding affinity free energies from the docking complexes (glutamate-graphene family) suggest higher oxidized graphene-based glutamate molecular recognition than the pristine-Gr, with the following order of oxidized graphene derivatives according to ab initio results: (Gr-O∼Gr-COOH ∼ Gr-COH > Gr-OH)>pristine-Gr. Herein, the ab initio binding energies found for the glutamate-graphene family complexes are in the range of 0.24-0.80 eV. The configurations studied showed a biophysical adsorption regime without significant changes in the physico-chemical properties of the adsorbed glutamate neurotransmitter, in accordance with the general acceptance criteria of the detection systems.

Interaction of CO and CH4 Adsorption with Noble Metal (Rh, Pd, and Pt)-Decorated N3-CNTs: A First-Principles Study

Using a first-principles theory, the structural and electronic behaviors of noble metal atom (Rh, Pd, and Pt)-decorated N3-CNTs were investigated. Meanwhile, the adsorption behavior of CO and CH4 molecules onto Rh-, Pd-, and Pt-decorated N3-CNTs was studied as well to exploit their potential applications. Results indicate that noble metal atoms are likely to be adsorbed on the N3 center of pyridine-like N3-CNTs under electrophilic attack. Moreover, the noble metal-embedded N3 group would provide CNTs with enhanced performance for gas adsorption compared with noble metal-embedded surfaces because of the improvement of chemical activity and electron mobility in our proposed configurations. The findings in this report would be beneficial for exploiting a possible adsorbent for CO scavenging with excellent adsorbing ability and a possible sensor for CH4 detection with good sensitivity and recovery behavior.

Comparison of X12Y12 (X=Al, B and Y=N, P) fullerene-like nanoclusters toward adsorption of dimethyl ether

Density functional theory (DFT) was used for studying the adsorption of dimethyl ether (DME) onto four nanoclusters: [Formula: see text] ([Formula: see text], B and [Formula: see text], P). The interaction energy along with the adsorption energy was investigated, and it was found that DME molecule has higher binding energies upon adsorption on Al-containing clusters, but on the other hand, it results in higher alteration in the electronic structure of B-containing cluster. Outcomes of charge analysis and frontier molecular orbital confirm higher alteration in the electronic structure of the later clusters, suggesting the possible potential of B[Formula: see text]N[Formula: see text] and B[Formula: see text]P[Formula: see text] as two sensitive sensors for DME. Nevertheless, Al-containing clusters showed much better adsorbent property, judging from their higher adsorption energies. The positive values of charge transfer upon DME adsorption confirm the p-type semiconducting property of all these clusters.

Theoretical study of the CO, NO, and N2 adsorptions on Li-decorated graphene and boron-doped graphene

The adsorption properties of common gas molecules (CO, NO, and N2) on the surface of Li-decorated pristine graphene and Li-decorated boron doped graphene are investigated using density functional theory. The adsorption energy, charge transfer, and density of states of gas molecules on three surfaces have been calculated and discussed, respectively. The results show that Li-decorated pristine graphene has strong interaction with CO and N2. Compared with Li-decorated pristine graphene, Li-decorated boron doped graphene exhibit a comparable adsorption ability of CO and N2. Moreover, Li-decorated boron doped graphene have a more significant adsorption energy to NO than that of Li-decorated pristine graphene because of the chemical interaction of the NO gas molecule. The strong interaction between the NO molecule and substrate (Li-decorated boron doped graphene) induces dramatic changes to the electrical conductivity of Li-decorated boron doped graphene. The results indicate that Li-decorated boron doped graphene would be an excellent candidate for sensing NO gas.

Activated carbons modified by magnesium oxide as highly efficient sorbents for acetone

Porous activated carbon modified with MgO was synthesized by an evaporation-induced self-assembly (EISA) method for its application to acetone capture.

High ozone chemisorption by using metal–cluster complexes: a DFT study on the nickel-decorated B12P12 nanoclusters

In the present study, by using first-principle study within the density functional theory (DFT), we investigated the ozone (O3) chemisorption on the surface of pristine and nickel-decorated B12P12 nanoclusters. The important emphasis of this study is to follow changes in the electronic structures of the aforementioned nanoclusters upon adsorption of the O3 molecule. Although we found strong chemisorption of O3 on a pristine nanocluster (–282.7 kJ/mol), significant increases in adsorption were found by modifying the nanocluster’s surface. Firstly, we found there are three possible sites on the surface of the nanocluster for nickel (Ni) decoration. For each Ni-decorated nanocluster, we searched its potential for adsorption of O3 by using quantum chemical calculations. Depending on the location of decorated Ni, we found considerable increased values of O3 adsorption energy (–340.8, –376.8, and –382.4 kJ/mol). We carried out calculations by taking into account the values of adsorption energy, bond distance, dipole moment study, charge analysis, frontier orbital analysis, and density of states of all relaxed systems.

Synthesis of Graphene-Based Sensors and Application on Detecting SF6 Decomposing Products: A Review

Graphene-based materials have aroused enormous focus on a wide range of engineering fields because of their unique structure. One of the most promising applications is gas adsorption and sensing. In electrical engineering, graphene-based sensors are also employed as detecting devices to estimate the operation status of gas insulated switchgear (GIS). This paper reviews the main synthesis methods of graphene, gas adsorption, and sensing mechanism of its based sensors, as well as their applications in detecting SF₆ decomposing products, such as SO₂, H₂S, SO₂F₂, and SOF₂, in GIS. Both theoretical and experimental researches on gas response of graphene-based sensors to these typical gases are summarized. Finally, the future research trend about graphene synthesis technique and relevant perspective are also given.