Mechano-Catalysis: Cyclohexane Oxidation in a Silver Nanowire Break Junction

Boer, Duncan den; Shklyarevskiǐ, O. I.; Coenen, Michiel J. J.; Maas, Minko van der; Peters, Theo P. J.; Elemans, Johannes A. A. W.; Speller, S.

doi:10.1021/jp111444c

Cited by 11 publications

(16 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In contrast, the ∼1.3 G 0 conductance was assigned to an Ag-Ag singleatom contact with one oxygen atom connected in a parallel arrangement (AgO-P). Similar experimental results and interpretations were also reported by den Boer et al 7 In order to explain the ∼1.3 G 0 conductance feature, one must assume that the Ag-O bonds are in parallel to the Ag-Ag bond in the AgO-P contact and thus the total conductance of the AgO-P contact is the sum of the Ag single-atom conductance and the oxygen atom conductance. 5,7 However, this assumption is questionable because the Ag-O bond is a strong ionic bond that will perturb significantly the electronic states of the Ag-Ag contact around the Fermi level.…”

Section: Introductionsupporting

confidence: 80%

“…Similar experimental results and interpretations were also reported by den Boer et al 7 In order to explain the ∼1.3 G 0 conductance feature, one must assume that the Ag-O bonds are in parallel to the Ag-Ag bond in the AgO-P contact and thus the total conductance of the AgO-P contact is the sum of the Ag single-atom conductance and the oxygen atom conductance. 5,7 However, this assumption is questionable because the Ag-O bond is a strong ionic bond that will perturb significantly the electronic states of the Ag-Ag contact around the Fermi level. Although many theoretical studies on the effects of oxygen atoms or molecules on the electronic transport properties of silver atomic contacts have been reported, [8][9][10][11][12][13] the microscopic origin of the ∼1.3 G 0 conductance feature is still unclear.…”

Section: Introductionsupporting

confidence: 80%

See 1 more Smart Citation

Microscopic origin of the 1.3 G conductance observed in oxygen-doped silver quantum point contacts

Wang

Sanvito

et al. 2014

The Journal of Chemical Physics

View full text Add to dashboard Cite

Besides the peak at one conductance quantum, G0, two additional features at ∼0.4 G0 and ∼1.3 G0 have been observed in the conductance histograms of silver quantum point contacts at room temperature in ambient conditions. In order to understand such feature, here we investigate the electronic transport and mechanical properties of clean and oxygen-doped silver atomic contacts by employing the non-equilibrium Green's function formalism combined with density functional theory. Our calculations show that, unlike clean Ag single-atom contacts showing a conductance of 1 G0, the low-bias conductance of oxygen-doped Ag atomic contacts depends on the number of oxygen impurities and their binding configuration. When one oxygen atom binds to an Ag monatomic chain sandwiched between two Ag electrodes, the low-bias conductance of the junction always decreases. In contrast, when the number of oxygen impurities is two and the O-O axis is perpendicular to the Ag-Ag axis, the transmission coefficients at the Fermi level are, respectively, calculated to be 1.44 for the junction with Ag(111) electrodes and 1.24 for that with Ag(100) electrodes, both in good agreement with the measured value of ∼1.3 G0. The calculated rupture force (1.60 nN for the junction with Ag(111) electrodes) is also consistent with the experimental value (1.66 ± 0.09 nN), confirming that the measured ∼1.3 G0 conductance should originate from Ag single-atom contacts doped with two oxygen atoms in a perpendicular configuration.

show abstract

Section: Introductionsupporting

confidence: 80%

Section: Introductionsupporting

confidence: 80%

Microscopic origin of the 1.3 G conductance observed in oxygen-doped silver quantum point contacts

Wang

Sanvito

et al. 2014

The Journal of Chemical Physics

View full text Add to dashboard Cite

show abstract

“…Although not as popular as gold, Ag and Pt are often employed as electrode materials for constructing molecular junctions. [36][37][38][39][40][41][42][43][44] Silver and gold are both noble metals whose density of states (DOS) around E F is dominated by s-type orbitals, while platinum is a transition metal having a DOS with strong d-character around the Fermi level. Thus, it is interesting to establish whether the electronic transport properties of vacuum-spaced junctions constructed with Ag and Au electrodes are significantly different from those made with Pt.…”

Section: Introductionmentioning

confidence: 99%

Transition voltages of vacuum-spaced and molecular junctions with Ag and Pt electrodes

Bai

Sanvito

et al. 2014

The Journal of Chemical Physics

View full text Add to dashboard Cite

The transition voltage of vacuum-spaced and molecular junctions constructed with Ag and Pt electrodes is investigated by non-equilibrium Green's function formalism combined with density functional theory. Our calculations show that, similarly to the case of Au-vacuum-Au previously studied, the transition voltages of Ag and Pt metal-vacuum-metal junctions with atomic protrusions on the electrode surface are determined by the local density of states of the p-type atomic orbitals of the protrusion. Since the energy position of the Pt 6p atomic orbitals is higher than that of the 5p/6p of Ag and Au, the transition voltage of Pt-vacuum-Pt junctions is larger than that of both Ag-vacuum-Ag and Au-vacuum-Au junctions. When one moves to analyzing asymmetric molecular junctions constructed with biphenyl thiol as central molecule, then the transition voltage is found to depend on the specific bonding site for the sulfur atom in the thiol group. In particular agreement with experiments, where the largest transition voltage is found for Ag and the smallest for Pt, is obtained when one assumes S binding at the hollow-bridge site on the Ag/Au(111) surface and at the adatom site on the Pt(111) one. This demonstrates the critical role played by the linker-electrode binding geometry in determining the transition voltage of devices made of conjugated thiol molecules.

show abstract

“…Understanding the mechanical properties and the mechanisms that control the conductance in atomic-scale wires is important both from a basic science standpoint and for applications in nanoelectronics and nano-devices. Numerous experimental studies [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] have been conducted to characterize the mechanical properties and the conductance of silver nanowires during elongation. In these experimental systems, the silver NW is elongated and thinned down to a single atom chain (SAC) in a high vacuum chamber, at ≈4 K. During wire thinning, the conductance is continuously 1 On sabbatical leave from the Nuclear Research Center Negev.…”

Section: Introductionmentioning

confidence: 99%

“…It is well known that the conductance is affected when impurities are pre-placed directly on the SAC [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51]. Experimental and theoretical studies [14][15][16][35][36][37][38] show that when O 2 is introduced to a SAC of silver, the conductance can decrease well below 1 G 0 . However, the ability of the O 2 to migrate from the surface of the 3D NWs to the region of the SAC during the elongation, and the effect of the O 2 on the conductance in the 3D and the 2D intermediate structures are still unknown.…”

Section: Introductionmentioning

confidence: 99%

Ab initiostudy of the mechanical and transport properties of pure and contaminated silver nanowires

Barzilai¹,

Tavazza²,

Levine³

2013

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The mechanical properties and conductance of contaminated and pure silver nanowires were studied using density functional theory (DFT) calculations. Several nanowires containing O2 on their surfaces were elongated along two different directions. All of the NWs thinned down to single atom chains. In most simulations, the breaking force was not affected by the presence of the O2, and similar fracture strengths of ≈1 nN were computed for the pure and impure NWs. When the O2 became incorporated in the single atom chain, the fracture occurred at the Ag-O bond and a lower fracture strength was found. All of the simulations showed that the impurity interacted with the silver atoms to reduce the electron density in its nearby vicinity. A variety of conductance effects were observed depending on the location of the impurity. When the impurity migrated during the elongation to the thinnest part of the NW, it reduced the conductance significantly, and an ≈1 G0 conductance (usually associated with a single atom chain) was calculated for three- and two-dimensional structures. When the impurity was adjacent to the single atom chain, the conductance reduced almost to zero. However, when it stayed far from the thinnest part of the NW, the impurity had only a small influence on the conductance.

show abstract

Mechano-Catalysis: Cyclohexane Oxidation in a Silver Nanowire Break Junction

Cited by 11 publications

References 46 publications

Microscopic origin of the 1.3 G conductance observed in oxygen-doped silver quantum point contacts

Microscopic origin of the 1.3 G conductance observed in oxygen-doped silver quantum point contacts

Transition voltages of vacuum-spaced and molecular junctions with Ag and Pt electrodes

Ab initiostudy of the mechanical and transport properties of pure and contaminated silver nanowires

Contact Info

Product

Resources

About