Sensing Properties of Vacancy and Pd-Doped Graphene Layer: A First-Principles Study

Abstract In this paper, the effect of SO2 adsorption on graphene (intrinsic, vacancy, and doped) is investigated for structural and electronic properties to exploit their potential applications as a gas sensor. The adsorption energy, charge transfer, magnetic moment, density of states, as well as band structure of the SO2 molecule on the vacancy and doped graphene systems are thoroughly discussed. The most stable adsorption site for SO2 on various graphene sheets is also identified and reported. It is found that SO2 molecule is weakly adsorbed on intrinsic graphene (IG) with low adsorption energy. In contrast, vacancy defect and Pd doping significantly enhance the strength of interaction between SO2 molecule and the modified substrates. The dramatic increase in adsorption energy and charge transfer of these systems are expected to induce significant changes in the electrical conductivity of the vacancy graphene (VG) and Pd-doped graphene (PdG) sheets. Furthermore, the results present the potential of Pd-doped vacancy graphene (Pd-VG) for molecular sensor application.

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Performance of Intrinsic and Modified Graphene for the Adsorption of H2S and CH4: A DFT Study

Nanomaterials ◽

10.3390/nano10020299 ◽

2020 ◽

Vol 10 (2) ◽

pp. 299 ◽

Cited By ~ 9

Author(s):

Xin Gao ◽

Qu Zhou ◽

Jingxuan Wang ◽

Lingna Xu ◽

Wen Zeng

Keyword(s):

Charge Transfer ◽

Density Functional ◽

Dft Method ◽

Vacancy Defect ◽

Single Vacancy ◽

Strength Of Interaction ◽

Before And After ◽

Doped Graphene ◽

Weak Adsorption ◽

Modified Graphene

In this study, the adsorption performances of graphene before and after modification to H2S and CH4 molecules were studied using first principles with the density functional theory (DFT) method. The most stable adsorption configuration, the adsorption energy, the density of states, and the charge transfer are discussed to research the adsorption properties of intrinsic graphene (IG), Ni-doped graphene (Ni–G), vacancy defect graphene (DG), and graphene oxide (G–OH) for H2S and CH4. The weak adsorption and charge transfer of IG achieved different degrees of promotion by doping the Ni atom, setting a single vacancy defect, and adding oxygen-containing functional groups. It can be found that a single vacancy defect significantly enhances the strength of interaction between graphene and adsorbed molecules. DG peculiarly shows excellent adsorption performance for H2S, which is of great significance for the study of a promising sensor for H2S gas.

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Al-doped graphene as an effective adsorber for some toxic derivatives of aromatic hydrocarbons

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633617500043 ◽

2017 ◽

Vol 16 (01) ◽

pp. 1750004 ◽

Cited By ~ 2

Author(s):

Min Ji ◽

Xinlu Cheng ◽

Weidong Wu

Keyword(s):

Charge Transfer ◽

Aromatic Hydrocarbons ◽

Adsorption Energy ◽

Density Functional ◽

Hydroxyl Group ◽

The Density Functional Theory ◽

Doped Graphene ◽

Perfect Graphene ◽

Hydrocarbons Adsorption ◽

Derivatives Of

The density functional theory (DFT) was used to investigate some toxic derivatives of aromatic hydrocarbons adsorption on perfect graphene (pG) and graphene-doped with B/Al/Ga (BG/AlG/GaG). And the parallel and vertical adsorptions were considered for the position relation between the adsorbent and adsorbate. The adsorption energy, adsorption distance, charge transfer and density of states (DOS) were discussed in optimized structures. The greater adsorption energy, shorter adsorption distance and more charge transfer were found in AlG by studying the four kinds of molecules (phenol/m-cresol/PCP/p-NP) adsorption on pG/BG/AlG/GaG. Then, 10 derivatives adsorption on AlG were reported, and the adsorption energy increased in the order of pentachlorophenol [Formula: see text] 2,4,6-trichlorophenol [Formula: see text] 2,4-dichlorophenol [Formula: see text] p-cresol [Formula: see text] m-cresol [Formula: see text] phenol [Formula: see text] o-chlorophenol [Formula: see text] o-cresol [Formula: see text] 2,4,6-trintrotoluene [Formula: see text] para-nitrophenol. The interaction between these derivatives and the substrate was chemisorption for AlG and physisorption for pG. The oxygen atom in nitro group was more closer to the substrate than in hydroxyl group about optimized structures.

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

Canadian Journal of Chemistry ◽

10.1139/cjc-2017-0346 ◽

2018 ◽

Vol 96 (1) ◽

pp. 30-39 ◽

Cited By ~ 1

Author(s):

Yao-Dong Song ◽

Liang Wang ◽

Li-Ming Wu

Keyword(s):

Strong Interaction ◽

Adsorption Energy ◽

Density Functional ◽

Chemical Interaction ◽

Energy Charge ◽

Pristine Graphene ◽

Functional Theory ◽

Boron Doped ◽

Doped Graphene ◽

Gas Molecules

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.

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Quantum Calculation of Proton and Other Charge Transfer Steps in Voltage Sensing in the Kv1.2 Channel

10.26434/chemrxiv.8251073 ◽

2019 ◽

Author(s):

Alisher M Kariev ◽

Michael Green

Keyword(s):

Charge Transfer ◽

Energy Charge ◽

Quantum Calculation ◽

Quantum Calculations ◽

Gating Current ◽

Transmembrane Segment ◽

Voltage Sensing ◽

Standard Models ◽

Charge Displacement ◽

Voltage Sensing Domain

Quantum calculations on 976 atoms of the voltage sensing domain of the Kv1.2 channel, with protons in several positions, give energy, charge transfer, and other properties. Motion of the S4 transmembrane segment that accounts for gating current in standard models is shown not to occur; there is H+ transfer instead. The potential at which two proton positions cross in energy approximately corresponds to the gating potential for the channel. The charge displacement seems approximately correct for the gating current. Two mutations are accounted for (Y266F, R300cit, cit =citrulline). The primary conclusion is that voltage sensing depends on H+ transfer, not motion of arginine charges.

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Synthesis and Photobehavior of a NewDehydrobenzoannulene-Based HOF with Fluorine Atoms: From Solution to Single Crystals Observation

International Journal of Molecular Sciences ◽

10.3390/ijms22094803 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4803

Author(s):

Eduardo Gomez ◽

Ichiro Hisaki ◽

Abderrazzak Douhal

Keyword(s):

Charge Transfer ◽

Single Crystals ◽

Parent Compound ◽

Time Resolved ◽

Strong Basis ◽

Triplet Structure ◽

Carboxylic Groups ◽

Potential Applications ◽

A Charge ◽

Further Development

Hydrogen-bonded organic frameworks (HOFs) are the focus of intense scientific research due their potential applications in science and technology. Here, we report on the synthesis, characterization, and photobehavior of a new HOF (T12F-1(124TCB)) based on a dehydrobenzoannulene derivative containing fluorine atoms (T12F-COOH). This HOF exhibits a 2D porous sheet, which is hexagonally networked via H-bonds between the carboxylic groups, and has an interlayers distance (4.3 Å) that is longer than that of a typical π–π interaction. The presence of the fluorine atoms in the DBA molecular units largely increases the emission quantum yield in DMF (0.33, T12F-COOH) when compared to the parent compound (0.02, T12-COOH). The time-resolved dynamics of T12F-COOH in DMF is governed by the emission from a locally excited state (S1, ~ 0.4 ns), a charge-transfer state (S1(CT), ~ 2 ns), and a room temperature emissive triplet state (T1, ~ 20 ns), in addition to a non-emissive triplet structure with a charge-transfer character (T1(CT), τ = 0.75 µs). We also report on the results using T12F-ester. Interestingly, FLIM experiments on single crystals unravel that the emission lifetimes of the crystalline HOF are almost twice those of the amorphous ones or the solid T12F-ester sample. This shows the relevance of the H-bonds in the photodynamics of the HOF and provides a strong basis for further development and study of HOFs based on DBAs for potential applications in photonics.

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