Query: Interactions of gas molecules with monolayer MoSe2

Candidate papers:

abstract: We present a first principle study of interaction of toxic gas molecules (NO, NO2 and SO2) with monolayer MoSe2. The predicted order of sensitivity of gas molecule is NO2 SO2 NO. Adsorbed molecules strongly influence the electronic behaviour of monolayer MoSe2 by inducing impurity levels in the vicinity of Fermi energy. NO and SO2 is found to induce p type doping effect while semiconductor to metallic transitions occur on NO2 adsorption. Our findings may guide the experimentalist for fabricating sensor devices based on MoSe2 monolayer.
author_names: Munish Sharma

Pooja Jamdagni

Ashok Kumar

Pushpa Ahluwalia
title: Interactions of gas molecules with monolayer MoSe2: A first principle study
year: 2016

abstract: Dissolved gas analysis (DGA) in transformer oil is a workable approach to evaluate the operation status of transformers. In this paper, we proposed a Cu doped Se vacancy MoSe2 (Cu MoSe2) monolayer as a promising sensing material for DGA based on first principles theory. Three typical dissolved gases, namely, CO, C2H2, and C2H4, are the representatives to investigate the potential of the Cu MoSe2 monolayer upon their adsorption and sensing. Our results indicate that Cu doping causes strong n doping for the Se vacancy MoSe2 monolayer, and the Cu MoSe2 monolayer exhibits strong chemisorption the three gas molecules, with a calculated adsorption energy (Ead) of 1.25, 1.06, and 1.16 eV, respectively. Such strong interactions lead to remarkable changes in the electrical conductivity of the Cu MoSe2 monolayer, allowing its application as a resistance type sensor. Besides, work function (WF) analysis shows the potential of the Cu MoSe2 monolayer as a promising field effect transistor sensor as well. It is our hope that our work can stimulate more leading edge studies of the TM doped MoSe2 monolayer for sensing applications in many fields.
author_names: Sunzhi Yang

Xian-lin Chen

Zurong Gu

Tieyong Ling

Yanling Li

Shouxiao Ma
title: Cu Doped MoSe2 Monolayer: A Novel Candidate for Dissolved Gas Analysis in Transformer Oil
venue: ACS omega
year: 2020

abstract: Lattice defects and dielectric environment play a crucial role for 2D materials. Gas molecules can get physisorbed easily on the surface through van der Waals forces and can modify dramatically their electronic and optical properties. In this work, we investigate the impact of the physisorbed gas molecules on the optical properties of MoSe2 monolayers by means of low temperature photoluminescence (PL) More specifically, we focus on the physics of excitons localized by gas molecules. The associated PL peak is observed to show a systematic and large red shift with temperature and a blue shift with laser irradiation. Both energy shifts are explained in terms of thermal instability of the localization in combination with hopping effects. Finally, a model is presented, which can reproduce the experimental data with excellent agreement. Published under license by AIP Publishing. https:/doi.org/10.1063/1.5094118 In recent years, a lot of scientific research has been conducted to understand the electronic and optical properties of transition metal dichalcogenide (TMD) monolayers (MoS2, WSe2, 1 The interest in these materials is closely connected with the atomic vertical scale of these semiconductors. This geometrical property made the scientific community face new interesting physics and at the same time new technological opportunities and challenges. An effect related to the extreme surface to volume ratio is the huge influence of physisorption and chemisorption of gas molecules on the optical and electronic properties. This efficient interaction can be exploited to engineer the materials for related applications, for instance, chemical treatment for enhancing and tuning photoluminescence (PL) emission as well as gas sensing and biosensing using modulations in electronic and optical responses as fingerprints for physisorbed gas molecules. In this context, PL offers an elegant, low power consuming, and contactless tool. Furthermore, physisorption is strongly connected with other prominent effects on TMD monolayers, i.e. photo annealing and photo doping. Regarding optical properties, it has been shown that the exposure to low intensity visible laser light changes drastically the optical response of the material. On one hand, these effects have to be kept under control for research investigations, but, on the other hand, they can be used for technological applications such as reversible optical control of the doping. Even if the effects of physisorption are well documented in literature, discussions and comprehension of the physics of such effects on localized excitons are still missing. For this purpose, we present here a systematic experimental study on the impact of gas molecules present in air on optical properties of a MoSe2 monolayer via lowtemperature PL. We follow the temperature evolution of the localized excitons related to gas molecules (GM LX) We observe a large redshift, and we present a model that can reproduce the data with excellent agreement. Within the same approach, we analyze the evolution of the GM LX peak for different laser irradiation doses, where a blueshift of the peak is observed with increasing irradiation doses. We suggest that both the red shift and the blue shift can be explained by hopping between localized states. Finally, we also introduce an effective temperature particularly important at low temperature in order to describe the disorder potential induced by the physisorbed gas molecules. We focus our attention on a MoSe2 monolayer, that is, a paradigmatic compound of TMDs. Nevertheless, in comparison with other W based TMD monolayers, it shows cleaner optical spectra, a condition that allows us to isolate more easily the effects of the physisorbed gas molecules. Moreover, the possibility to use MoSe2 monolayers Appl. Phys. Lett. 114, 172106 (2019) doi: 10.1063/1.5094118 114, 172106 1 Published under license by AIP Publishing Applied Physics Letters ARTICLE scitation.org/journal/apl
author_names: Tommaso Venanzi

Himani Arora

Artur Erbe

Alexej Pashkin

Manfred Helm

Harald Schneider
title: Helmholtz Zentrum Dresden Rossendorf (HZDR) Exciton localization in MoSe2 monolayer induced by adsorbed gas molecules
year: 2020

abstract: Abstract The adsorptions of noble metals including Pd, Pt and Au atoms on the MoSe2 monolayers were explored using the density functional theory calculations. The results of the adsorption energies indicated that all Pd, Pt and Au adsorbed MoSe2 monolayers are energetically stable. Based on band structure calculations, all the noble metal adsorbed MoSe2 systems showed semiconductor feature. The smallest stability occurs in Au adsorption to the surface, whereas the highest stability corresponds to the Pt adsorption with the TM Se bond length being lower than that of Au adsorption system. Au adsorbed MoSe2 monolayer revealed magnetism, while Pd and Pt adsorbed monolayers possess nonmagnetic nature. The adsorption configurations of CO, CO2, NO, and NH3 molecules on the Pt adsorbed MoSe2 monolayers were also examined in this work. These gas molecules ae weakly physisorbed on the pure MoSe2 monolayer, while on the Pt adsorbed one, the gas molecules were strongly chemisorbed. The nature of covalent interaction between the gases and Pt adsorbed system can be also verified by large overlaps in the density of states plots.
author_names: Wang Si Hui

Gong Chang

Wei Gao
title: Exploring the electronic and magnetic properties of noble metal (Pd, Pt, Au) adsorbed MoSe2 monolayers and their performance towards sensing gas molecules
year: 2020

abstract: This paper explores the two dimensional (2D) MoSe2 materials and their sensing properties by exploring it to hazardous N2O gas molecule. The gas sensing behavior is analyzed with charge transfer (QT) as one of its parameter. Charge transfer is used to explain the extent to which the gas molecule interacts with the 2D material. A comparison between charge transfers by varying the adsorption distance between the adsorbent gas molecule and among adsorbent atoms from 2A to 1A with a uniform step of 0.5A is dealt with. The impact on the bond length is also analyzed and calculated to be decreasing with increase in charge transfer. It is observed that higher will be the charge transfer between the adsorbent gas molecule and 2D MoSe2 material, higher will be interaction.
author_names: Neha Mishra

Bramha P Pandey
title: Detection of N2O gas using 2D MoSe2 Monolayer: A DFT Theory
venue: 2020 International Conference on Electrical and Electronics Engineering (ICE3)
year: 2020

abstract: Using first principles theory, we investigated the most stable configuration for the Rh dopant on a MoSe2 monolayer, and the interaction of the Rh doped MoSe2 (Rh MoSe2) monolayer with four toxic gases (CO, NO, NO2 and SO2) to exploit the potential application of the Rh MoS2 monolayer as a gas sensor or adsorbent. Based on adsorption behavior comparison with other 2D adsorbents and desorption behavior analysis, we assume that the Rh MoSe2 monolayer is a desirable adsorbent for CO, NO and NO2 storage or removal given the larger adsorption energy (Ead) of 2.00, 2.56 and 1.88 eV, respectively, compared with other materials. In the meanwhile, the Rh MoSe2 monolayer is a good sensing material for SO2 detection according to its desirable adsorption and desorption behaviors towards the target molecule. Our theoretical calculation would provide a first insight into the TM doping effect on the structural and electronic properties of the MoSe2 monolayer, and shed light on the application of Rh MoSe2 for the sensing or disposal of common toxic gases.
author_names: Hao Cui

Guozhi Zhang

Xiaoxing Zhang

Ju Tang
title: Rh doped MoSe2 as a toxic gas scavenger: a first principles study
year: 2019

abstract: Abstract On the basis of recent findings reported, gas sensors constructed from MoS2 and MoSe2 monolayers have superior sensing performance compared to the gas sensors fabricated from graphene. In this work, we scrutinized the adsorption of NO, and CO gas molecules on the perfect and Ti doped MoS2 and MoSe2 monolayers by means of the density functional theory method. The obtained results revealed that the Ti doped MoS2 and MoSe2 monolayers have more sensitivity towards NO and CO detection than the pristine systems with substantial adsorption energies of gas molecules on these surfaces. The higher sensitivity and larger adsorption energy of Ti doped systems are responsible for the strong interaction between NO/CO molecules and MoS2/MoSe2 systems. There are considerable electronic density between the metal site of substrates and N/C atoms of NO/CO molecules, which can be attributed to the strong interaction between them. Moreover, the effect of external electric field on the adsorption process was evaluated, which indicates that the sensitivity of gas sensor can substantially be modulated via applying external electric field. This work aims at suggesting a promising material based on Ti doped MoS2 and MoSe2 systems for sensing toxic NO and CO gases in the atmosphere.
author_names: Yafeng Yang

Muhammad Ashraf

Kittisak Jermsittiparsert

Lilin Jiang

Dangquan Zhang
title: RETRACTED: Enhancing the adsorption performance and sensing capability of Ti doped MoSe2 and MoS2 monolayers by applying electric field
year: 2020

abstract: Recent experiments demonstrate the synthesis of 2D black arsenic exhibits excellent electronic and transport properties for nanoscale device applications. Herein, we study by first principle calculations density functional theory together with non equilibrium Greens function methods, the structural, electronic, adsorption strength, charge transfer, and transport properties of five gas molecules CO, CO2, NO, NO2, and NH3 on a monolayer of black arsenic. Our findings suggest optimum sensing performance of black arsenic that can even surpass that of other 2D material such as graphene. Further, we note the optimum adsorption sites for all the five gas molecules on the black arsenic and significant charge transfer between the gas molecules and black arsenic are responsible for optimum adsorption strength. Particularly, the significant charger transfer is a sign that the interaction between the target gas molecule and nanoscale device is sufficient to yield noticeable changes in the electronic transport properties. As a proof of principle, we have examined the sensitivity of a modeled nano scale device towards CO, CO2, NO, NO2, and NH3 gas molecules, indicating that it is indeed possible to reliably detect all the five gas molecules. Thus, based on all these findings, such as sensitivity and selectivity to all the five gas molecules adsorption make black arsenic a promising material as an optimum gas sensor nano scale device.
author_names: Rameshwar L Kumawat

Milan Kumar Jena

Biswarup Pathak Discipline of Metallurgy Engineering

Materials Science

Discipline of Chemistry

Indian Institute of Technology
title: Black Arsenic as an Optimum Gas Sensor: vdW Corrected Density Functional Theory Calculations
year: 2020

abstract: Using first principles theory, we investigated the most stable configuration for the Rh dopant on a MoSe2 monolayer, and the interaction of the Rh doped MoSe2 (Rh MoSe2) monolayer with four toxic gases (CO, NO, NO2 and SO2) to exploit the potential application of the Rh MoS2 monolayer as a gas sensor or adsorbent. Based on adsorption behavior comparison with other 2D adsorbents and desorption behavior analysis, we assume that the Rh MoSe2 monolayer is a desirable adsorbent for CO, NO and NO2 storage or removal given the larger adsorption energy (Ead) of 2.00, 2.56 and 1.88 eV, respectively, compared with other materials. In the meanwhile, the Rh MoSe2 monolayer is a good sensing material for SO2 detection according to its desirable adsorption and desorption behaviors towards the target molecule. Our theoretical calculation would provide a first insight into the TM doping effect on the structural and electronic properties of the MoSe2 monolayer, and shed light on the application of RhMoSe2 for the sensing or disposal of common toxic gases.
author_names: Hao Cui

Guozhi Zhang

Xiaoxing Zhang

J Tangc
title: as a toxic gas scavenger a fi rst principles study
year: 2019

abstract: In the monolayer limit, transition metal dichalcogenides become direct bandgap, light emitting semiconductors. The quantum yield of light emission is low and extremely sensitive to the substrate used, while the underlying physics remains elusive. In this work, we report over 100 times modulation of light emission efficiency of these two dimensional semiconductors by physical adsorption of O2 and/or H2O molecules, while inert gases do not cause such effect. The O2 and/or H2O pressure acts quantitatively as an instantaneously reversible "molecular gating" force, providing orders of magnitude broader control of carrier density and light emission than conventional electric field gating. Physi sorbed O2 and/or H2O molecules electronically deplete n type materials such as MoS2 and MoSe2, which weakens electrostatic screening that would otherwise destabilize excitons, leading to the drastic enhancement in photoluminescence. In p type materials such as WSe2, the molecular physisorption results in the opposite effect. Unique and universal in two dimensional semiconductors, the effect offers a new mechanism for modulating electronic interactions and implementing optical devices.
author_names: Sefaattin Tongay

Jian Zhou

Can Ataca

Jonathan Liu

Jeong Seuk Kang

Tyler Scott Matthews

Long You

Jingbo Li

Jeffrey C Grossman

Junqiao Wu
title: Broad range modulation of light emission in two dimensional semiconductors by molecular physisorption gating.
venue: Nano letters
year: 2013