The Adsorption and Sensing Performances of Ir-modified MoS2 Monolayer toward SF6 Decomposition Products: A DFT Study

In this paper, the Ir-modified MoS2 monolayer is suggested as a novel gas sensor alternative for detecting the characteristic decomposition products of SF6, including H2S, SO2, and SOF2. The corresponding adsorption properties and sensing behaviors were systematically studied using the density functional theory (DFT) method. The theoretical calculation indicates that Ir modification can enhance the surface activity and improve the conductivity of the intrinsic MoS2. The physical structure formation, the density of states (DOS), deformation charge density (DCD), molecular orbital theory analysis, and work function (WF) were used to reveal the gas adsorption and sensing mechanism. These analyses demonstrated that the Ir-modified MoS2 monolayer used as sensing material displays high sensitivity to the target gases, especially for H2S gas. The gas sensitivity order and the recovery time of the sensing material to decomposition products were reasonably predicted. This contribution indicates the theoretical possibility of developing Ir-modified MoS2 as a gas sensor to detect characteristic decomposition gases of SF6.

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First Principles Study on Rutile SnO2 Improving Gas Sensor Properties of Porous SnO2-In2O3 Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.476-478.828 ◽

2012 ◽

Vol 476-478 ◽

pp. 828-834

Author(s):

Yu Cao ◽

Xiao Long Zhou ◽

Jian Chun Cao ◽

Yuan Yuan Peng ◽

Jing Chao Chen ◽

...

Keyword(s):

Composite Materials ◽

Gas Sensor ◽

First Principles ◽

Density Functional ◽

Co Adsorption ◽

Gas Sensitivity ◽

Rutile Structure ◽

X Ray ◽

Sensor Properties ◽

Reduced Surface

we built the rutile SnO2 to study SnO2 improving gas sensor properties for rutile structure of SnO2 existing in the SnO2-In2O3 composite materials by X-ray analysis. The surface (110) of SnO2 is a stable structure by analysis of surface energy. Compared with oxidized surface (110), reduced surface (110) has better conductivity and stability. As a result, the CO adsorption changes the electric conductivity of the whole reductive (110) surface, and leads to the deviation of Fermi energy. Therefore, it is an important reason affecting gas sensor properties of the SnO2-In2O3 composite materials. By calculating and simulating the density functional first-principal, the research of the adsorption of rutile SnO2 towards CO provides a theoretical foundation for the argument of the gas sensitivity of porous SnO2-In2O3 composite materials towards CO with the increasing of SnO2 contents.

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The Adsorption Behavior of Gas Molecules on Co/N Co–Doped Graphene

Molecules ◽

10.3390/molecules26247700 ◽

2021 ◽

Vol 26 (24) ◽

pp. 7700

Author(s):

Tingyue Xie ◽

Ping Wang ◽

Cuifeng Tian ◽

Guozheng Zhao ◽

Jianfeng Jia ◽

...

Keyword(s):

Magnetic Properties ◽

Gas Sensor ◽

Density Functional ◽

Gas Adsorption ◽

Adsorption Behavior ◽

Spintronic Devices ◽

So2 Adsorption ◽

Doped Graphene ◽

Gas Molecules ◽

Co Doped

Herein, we have used density functional theory (DFT) to investigate the adsorption behavior of gas molecules on Co/N3 co–doped graphene (Co/N3–gra). We have investigated the geometric stability, electric properties, and magnetic properties comprehensively upon the interaction between Co/N3–gra and gas molecules. The binding energy of Co is −5.13 eV, which is big enough for application in gas adsorption. For the adsorption of C2H4, CO, NO2, and SO2 on Co/N–gra, the molecules may act as donors or acceptors of electrons, which can lead to charge transfer (range from 0.38 to 0.7 e) and eventually change the conductivity of Co/N–gra. The CO adsorbed Co/N3–gra complex exhibits a semiconductor property and the NO2/SO2 adsorption can regulate the magnetic properties of Co/N3–gra. Moreover, the Co/N3–gra system can be applied as a gas sensor of CO and SO2 with high stability. Thus, we assume that our results can pave the way for the further study of gas sensor and spintronic devices.

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Ni-CNT Chemical Sensor for SF6 Decomposition Components Detection: A Combined Experimental and Theoretical Study

Sensors ◽

10.3390/s18103493 ◽

2018 ◽

Vol 18 (10) ◽

pp. 3493 ◽

Cited By ~ 6

Author(s):

Yingang Gui ◽

Xiaoxing Zhang ◽

Peigeng Lv ◽

Shan Wang ◽

Chao Tang ◽

...

Keyword(s):

Gas Sensor ◽

Density Functional ◽

Chemical Sensor ◽

Theoretical Study ◽

Gas Sensing ◽

Limit Of Detection ◽

Gas Sensitivity ◽

Sensitivity And Selectivity ◽

Sf6 Decomposition ◽

Insulation Status

SF6 decomposition components detection is a key technology to evaluate and diagnose the insulation status of SF6-insulated equipment online, especially when insulation defects-induced discharge occurs in equipment. In order to detect the type and concentration of SF6 decomposition components, a Ni-modified carbon nanotube (Ni-CNT) gas sensor has been prepared to analyze its gas sensitivity and selectivity to SF6 decomposition components based on an experimental and density functional theory (DFT) theoretical study. Experimental results show that a Ni-CNT gas sensor presents an outstanding gas sensing property according to the significant change of conductivity during the gas molecule adsorption. The conductivity increases in the following order: H2S > SOF2 > SO2 > SO2F2. The limit of detection of the Ni-CNT gas sensor reaches 1 ppm. In addition, the excellent recovery property of the Ni-CNT gas sensor makes it easy to be widely used. A DFT theoretical study was applied to analyze the influence mechanism of Ni modification on SF6 decomposition components detection. In summary, the Ni-CNT gas sensor prepared in this study can be an effective way to evaluate and diagnose the insulation status of SF6-insulated equipment online.

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Adsorption Properties of Pd3-Modified Double-Vacancy Defect Graphene toward SF6 Decomposition Products

Sensors ◽

10.3390/s20154188 ◽

2020 ◽

Vol 20 (15) ◽

pp. 4188

Author(s):

Jie Li ◽

Lei Pang ◽

Fuwei Cai ◽

Xieyu Yuan ◽

Fanyu Kong

Keyword(s):

Density Functional ◽

Gas Adsorption ◽

Energy Gap ◽

Density Functional Theory Calculations ◽

Vacancy Defect ◽

Microscopic Mechanism ◽

Decomposition Products ◽

Adsorption Structure ◽

Sf6 Decomposition ◽

Operation Status

In this study, we investigate Pd3-cluster-modified 555–777 graphene (Pd3-graphene) as a novel resistor-type gas sensor to detect SF6 decomposition products based on density functional theory calculations. We obtained and minutely analyzed the relevant parameters of each most stable adsorption configuration to explore the microscopic mechanism during gas adsorption. Theoretical results reveal that Pd3-graphene shows great adsorption capacity and sensitivity toward those decompositions. High adsorption energies and abundant charge transfer amounts could guarantee a stable adsorption structure of decomposition gases on Pd3-graphene surface. The complex change of density of states verifies a strong chemical reaction between the gases and the surface. Moreover, the conductivity of Pd3-graphene would improve due to the decrease of energy gap, and the sensitivity was calculated as SOF2 > H2S > SO2 > SO2 F2. This work provides an effective method to evaluate the operation status of SF6 gas-insulated equipment.

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First-Principle Insight into Ga-Doped MoS2 for Sensing SO2, SOF2 and SO2F2

Nanomaterials ◽

10.3390/nano11020314 ◽

2021 ◽

Vol 11 (2) ◽

pp. 314

Author(s):

Wenjun Hou ◽

Hongwan Mi ◽

Ruochen Peng ◽

Shudi Peng ◽

Wen Zeng ◽

...

Keyword(s):

Density Functional ◽

Sulfur Hexafluoride ◽

Gas Sensing ◽

Electrical Equipment ◽

First Principle ◽

Adsorption Parameters ◽

Adsorption Effect ◽

Mos2 Monolayer ◽

Sensing Material ◽

Weak Adsorption

First-principle calculations were carried out to simulate the three decomposition gases (SO2, SOF2, and SO2F2) of sulfur hexafluoride (SF6) on Ga-doped MoS2 (Ga-MoS2) monolayer. Based on density functional theory (DFT), pure MoS2 and multiple gas molecules (SF6, SO2, SOF2, and SO2F2) were built and optimized to the most stable structure. Four types of Ga-doped positions were considered and it was found that Ga dopant preferred to be adsorbed by the top of Mo atom (TMo). For the best adsorption effect, two ways of SO2, SOF2, and SO2F2 to approach the doping model were compared and the most favorable mode was selected. The adsorption parameters of Ga-MoS2 and intrinsic MoS2 were calculated to analyze adsorption properties of Ga-MoS2 towards three gases. These analyses suggested that Ga-MoS2 could be a good gas-sensing material for SO2 and SO2F2, while it was not suitable for SOF2 sensing due to its weak adsorption. This work provides a theoretical basis for the development of Ga-MoS2 materials with the hope that it can be used as a good gas-sensing material for electrical equipment.

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DFT METHOD STUDY ON LUBRICANT PROPERTIES OF DISULFIDE COMPOUNDS AS EXTREME PRESSURE ADDITIVE

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633606002076 ◽

2006 ◽

Vol 05 (01) ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

XUE-YE WANG ◽

XIN-FANG LI ◽

XIAO-HONG WEN ◽

YUAN-QIANG TAN

Keyword(s):

Density Functional ◽

Wear Test ◽

Dft Method ◽

Basis Set ◽

Frontier Molecular Orbital ◽

Extreme Pressure ◽

Structure Property ◽

Wear Properties ◽

Orbital Theory ◽

Tribochemical Reaction

The molecular geometries optimization and electronic structures of fourteen disulfide compounds had been investigated by density functional theory (DFT) at 6-31G basis set level. The active atoms and active bonds of tribochemical reaction were obtained according to frontier molecular orbital theory, and the interaction energy of chemical adsorption between disulfides and metal surfaces were calculated. The structure-property relationship had been discussed with satisfactory results. The calculated results indicated that the S–S bond and C–S bond of compounds are trended to be broken when organic disulfide compounds interact with a metal, and the order of anti-wear properties for disulfide compounds: diphenyldisulfide >dibenzyldisulfide >di-n-dodecyldisulfide >di-n-octyldisulfide >di-n-butyldisulfide >diethyldisulfide, the extreme pressure properties of DBDS is superior to that of DPDS. The predicted results based on quantum chemical calculations are in excellent agreement with friction and wear test results.

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Nitrogen-Containing Gas Sensing Properties of 2-D Ti2N and Its Derivative Nanosheets: Electronic Structures Insight

Nanomaterials ◽

10.3390/nano11092459 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2459

Author(s):

Hongni Zhang ◽

Wenzheng Du ◽

Jianjun Zhang ◽

Rajeev Ahuja and Zhao Qian

Keyword(s):

Density Functional ◽

Gas Adsorption ◽

Gas Sensing ◽

Density Functional Theory Calculations ◽

Fast Response ◽

Two Dimensional ◽

Sensing Applications ◽

Sensing Material ◽

Physical Insight ◽

The Stability

In this work, the potentials of two-dimensional Ti2N and its derivative nanosheets Ti2NT2(T=O, F, OH) for some harmful nitrogen-containing gas (NCG) adsorption and sensing applications have been unveiled based on the quantum-mechanical Density Functional Theory calculations. It is found that the interactions between pure Ti2N and NCGs (including NO, NO2, and NH3 in this study) are very strong, in which NO and NO2 can even be dissociated, and this would poison the substrate of Ti2N monolayer and affect the stability of the sensing material. For the monolayer of Ti2NT2(T=O, F, OH) that is terminated by functional groups on surface, the adsorption energies of NCGs are greatly reduced, and a large amount of charges are transferred to the functional group, which is beneficial to the reversibility of the sensing material. The significant changes in work function imply the good sensitivity of the above mentioned materials. In addition, the fast response time further consolidates the prospect of two-dimensional Ti2NT2 as efficient NCGs’ sensing materials. This theoretical study would supply physical insight into the NCGs’ sensing mechanism of Ti2N based nanosheets and help experimentalists to design better 2-D materials for gas adsorption or sensing applications.

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Influence of intramolecular interactions on carbon dioxide gas adsorption capacity in Mesoporous Imine polymers

10.26434/chemrxiv.5826435 ◽

2018 ◽

Author(s):

Jaya Prakash Madda ◽

Pilli Govindaiah ◽

Sushant Kumar Jena ◽

Sabbhavat Krishna ◽

Rupak Kishor

Keyword(s):

Carbon Dioxide ◽

Adsorption Capacity ◽

Density Functional ◽

Gas Adsorption ◽

Ambient Pressure ◽

Condensation Reaction ◽

Intramolecular Interactions ◽

Carbon Dioxide Adsorption ◽

Nitrogen Gas ◽

Adsorption Characteristic

Covalent organic Imine polymers with intrinsic meso-porosity were synthesized by condensation reaction between 4,4-diamino diphenyl methane and (para/meta/ortho)-phthaladehyde. Even though these polymers were synthesized from precursors of bis-bis covalent link mode, the bulk materials were micrometer size particles with intrinsic mesoporous enables nitrogen as well as carbon dioxide adsorption in the void spaces. These polymers were showed stability up to 260o centigrade. Nitrogen gas adsorption capacity up to 250 cc/g in the ambient pressure was observed with type III adsorption characteristic nature. Carbon dioxide adsorption experiments reveal the possible terminal amine functional group to carbamate with CO2 gas molecule to the polymers. One of the imine polymers, COP-3 showed more carbon dioxide sorption capacity and isosteric heat of adsorption (Qst) than COP-1 and COP-2 at 273 K even though COP-3 had lower porosity for nitrogen gas than COP-1 and COP-2. We explained the trends in gas adsorption capacities and Qst values as a consequence of the intra molecular interactions confirmed by Density Functional Theory computational experiments on small molecular fragments.

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uMBD: A Materials-Ready Dispersion Correction that Uniformly Treats Metallic, Ionic, Covalent, and van der Waals Bonding

10.26434/chemrxiv.7938137.v2 ◽

2019 ◽

Author(s):

Minho Kim ◽

won june kim ◽

Tim Gould ◽

Eok Kyun Lee ◽

Sébastien Lebègue ◽

...

Keyword(s):

First Principles ◽

Density Functional ◽

Electrode Materials ◽

Full Range ◽

Van Der Waals ◽

Dft Method ◽

Dispersion Correction ◽

Computational Overhead ◽

System A ◽

Battery Design

Materials design increasingly relies on first-principles calculations for screening important candidates and for understanding quantum mechanisms. Density functional theory (DFT) is by far the most popular first-principles approach due to its efficiency and accuracy. However, to accurately predict structures and thermodynamics, DFT must be paired with a van der Waals (vdW) dispersion correction. Therefore, such corrections have been the subject of intense scrutiny in recent years. Despite significant successes in organic molecules, no existing model can adequately cover the full range of common materials, from metals to ionic solids, hampering the applications of DFT for modern problems such as battery design. Here, we introduce a universally optimized vdW-corrected DFT method that demonstrates an unbiased reliability for predicting molecular, layered, ionic, metallic, and hybrid materials without incurring a large computational overhead. We use our method to accurately predict the intercalation potentials of layered electrode materials of a Li-ion battery system – a problem for which the existing state-of-the-art methods fail. Thus, we envisage broad use of our method in the design of chemo-physical processes of new materials.

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