Density functional study the interaction of oxygen molecule with defect sites of graphene

Qi, Xuejun; Guo, Xiaoxia; Chen, Zheng

doi:10.1016/j.apsusc.2012.07.018

Cited by 48 publications

(26 citation statements)

References 33 publications

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“…Computational results demonstrated that a single oxygen atom is inclined to be chemisorbed on the bridge site of a defective graphene surface with exothermic reactions (e.g., binding of oxygen to Stone-Walls defects releases energy of −276 kJ mol -1 ). [ 54 ] In our case, the presence of defects is inferred from the D-peak in the Raman spectra shown in Figure 2 .…”

Section: Rational For the Charge Transfer And Chemical Modelmentioning

confidence: 99%

Graphene as an Electron Shuttle for Silver Deoxidation: Removing a Key Barrier to Plasmonics and Metamaterials for SERS in the Visible

Losurdo

Bergmair

Dastmalchi

et al. 2013

Adv Funct Materials

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The role of graphene in enabling deoxidation of silver nanostructures, thereby contributing to enhance plasmonic properties and to improve the temporal stability of graphene/silver hybrids for both general plasmonic and meta‐materials applications, as well as for surface enhanced Raman scattering (SERS) substrates, is demonstrated. The chemical mechanism occurring at the graphene–silver oxide interface is based on the reduction of silver oxide triggered by graphene that acts as a shuttle of electrons and as a kind of catalyst in the deoxidation. A mechanism is formulated, combining elements of electron transfer, role of defects in graphene, and electrochemical potentials of graphene, silver, and oxygen. Therefore, the formulated model represents a step forward from the simple view of graphene as barrier to oxygen diffusion proposed so far in literature. Single layer graphene grown by chemical vapor deposition is transferred onto silver thin films, a periodic silver fishnet structure fabricated by nanoimprint lithography, and onto silver nanoparticle ensembles supporting a localized surface plasmon resonance in the visible range. Through the study of these nanostructured graphene/Ag hybrids, the effectiveness of graphene in preventing and reducing oxidation of silver plasmonic structures, keeping silver in a metallic state over months at air exposure, is demonstrated. The enhanced and stable plasmonic properties of the silver‐fishnet/graphene hybrids are evaluated through their SERS response for detecting benzyl mercaptane.

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Section: Rational For the Charge Transfer And Chemical Modelmentioning

confidence: 99%

Graphene as an Electron Shuttle for Silver Deoxidation: Removing a Key Barrier to Plasmonics and Metamaterials for SERS in the Visible

Losurdo

Bergmair

Dastmalchi

et al. 2013

Adv Funct Materials

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“…A competition between SAC and hydrogen to saturate graphene vacancies can also occur during post‐synthesis treatments, like reduction or during catalysis in the presence of H 2 . If produced, these highly reactive sites are also able to easily react with small atmospheric molecules such as water or oxygen; in that case the vacancies (or edges) will be O‐terminated ,. Water and oxygen dissociate on SV with respective barriers of 1.6 and 0.2 eV, respectively .…”

Section: Types Of Carbon Materials For Single Atom Deposition and Natmentioning

confidence: 99%

Single Atom Catalysts on Carbon‐Based Materials

2018

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Metal particle size is an important parameter to consider when looking at supported catalyst performances. As for other properties, surface reactivity of metallic nanoparticles is thus highly size‐dependent. The smallest size that can be reached for this type of object is of course the isolated atom deposited on a support. The preparation of single‐atom catalysts (SAC) is not trivial, since to avoid clustering, the mean adsorption energy of the metal on the support should be higher than its cohesive energy. The choice of a support that allows a strongly interacting environment with the metal is therefore a key step in the preparation of such catalysts. The spectrum of carbon (nano)materials is very broad, and their structure as well as their surface chemistry, although sometime complex, can be tuned and exploited for the stabilization of SAC. This Review summarizes in a comprehensive manner experimental and computational studies aiming at: i) preparing SAC on carbon materials, ii) understanding the metal‐support interactions in SAC, and iii) studying how this relates to catalytic performances. The use of SAC follows well the needs dictated by society (energy and environment issues), and many studies have already been published in various fields, such as thermal catalysis, photocatalysis and electrocatalysis.

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“…Upon thermal annealing, the presence of C− −O− −C groups has also been reported. [41][42][43][44][45][46][47] It is important to realize that there are very few defects expected to be available on a freshly prepared HOPG surface and thus additional defects can be introduced intentionally by ion sputtering followed by annealing in oxygen. The chemical nature of both types of defects is expected to be similar based on the detailed previous studies; [48][49][50] however, the amount can be varied by varying the surface preparation conditions.…”

Section: Resultsmentioning

confidence: 99%

Deposition of copper from Cu(i) and Cu(ii) precursors onto HOPG surface: Role of surface defects and choice of a precursor

Duan

Teplyakov

2016

The Journal of Chemical Physics

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The surface reactivity of two copper-containing precursors, (Cu(hfac) 2 and Cu(hfac)VTMS, where hfac is hexafluoroacetyloacetonate and VTMS is vinyltrimethylsilane), was investigated by dosing the precursors onto a surface of highly ordered pyrolytic graphite (HOPG) at room temperature. The behavior of these precursors on a pristine HOPG was compared to that on a surface activated by ion sputtering and subsequent oxidation to induce controlled surface defects. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy were used to confirm copper deposition and its surface distribution, and to compare with the results of scanning electron microscopy and atomic force microscopy investigations. As expected, surface defects promote copper deposition; however, the specific structures deposited depend on the deposition precursor. Density functional theory was used to mimic the reactions of each precursor molecule on this surface and to determine the origins of this different reactivity. Published by AIP Publishing. [http://dx

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Density functional study the interaction of oxygen molecule with defect sites of graphene

Cited by 48 publications

References 33 publications

Graphene as an Electron Shuttle for Silver Deoxidation: Removing a Key Barrier to Plasmonics and Metamaterials for SERS in the Visible

Graphene as an Electron Shuttle for Silver Deoxidation: Removing a Key Barrier to Plasmonics and Metamaterials for SERS in the Visible

Single Atom Catalysts on Carbon‐Based Materials

Deposition of copper from Cu(i) and Cu(ii) precursors onto HOPG surface: Role of surface defects and choice of a precursor

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