References of "ACS Nano"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSulfur-Depleted Monolayered Molybdenum Disulfide Nanocrystals for Superelectrochemical Hydrogen Evolution Reaction
Lin, Liangxu; Miao, Naihua; Wen, Yan et al

in ACS Nano (2016), 10

Catalytically driven electrochemical hydrogen evolution reaction (HER) of monolayered molybdenum disulfide (MoS2) is usually highly suppressed by the scarcity of edges and low electrical conductivity ... [more ▼]

Catalytically driven electrochemical hydrogen evolution reaction (HER) of monolayered molybdenum disulfide (MoS2) is usually highly suppressed by the scarcity of edges and low electrical conductivity. Here, we show how the catalytic performance of MoS2 monolayers can be improved dramatically by catalyst size reduction and surface sulfur (S) depletion. Monolayered MoS2 nanocrystals (NCs) (2−25 nm) produced via exfoliating and disintegrating their bulk counterparts showed improved catalysis rates over monolayer sheets because of their increased edge ratios and metallicity. Subsequent S depletion of these NCs further improved the metallicity and made Mo atoms on the basal plane become catalytically active. As a result, the S-depleted NCs with low mass (∼1.2 μg) showed super high catalytic performance on HER with a low Tafel slope of ∼29 mV/decade, overpotentials of 60−75 mV, and high current densities jx (where x is in mV) of j150 = 9.64 mA·cm−2 and j200 = 52.13 mA·cm−2. We have found that higher production rates of H2 could not be achieved by adding more NC layers since HER only happens on the topmost surface and the charge mobility decreases dramatically. These difficulties can be largely alleviated by creating a hybrid structure of NCs immobilized onto three-dimensional graphene to provide a very high surface exposure of the catalyst for electrochemical HER, resulting in very high current densities of j150 = 49.5 mA·cm−2 and j200 = 232 mA·cm−2 with ∼14.3 μg of NCs. Our experimental and theoretical studies show how careful design and modification of nanoscale materials/structures can result in highly efficient catalysis. There may be considerable opportunities in the broader family of transition metal dichalcogenides beyond just MoS2 to develop highly efficient atomically thin catalysts. These could offer cheap and effective replacement of precious metal catalysts in clean energy production. [less ▲]

Detailed reference viewed: 22 (2 ULiège)
Full Text
Peer Reviewed
See detailCorrection to Aluminum Conducts Better than Copper at the Atomic Scale: A First-Principles Study of Metallic Atomic Wires
Simbeck, Adam J.; Lanzillo, Nick; Kharche, Neerav et al

in ACS nano (2015), 9(6), 6635--6635

Detailed reference viewed: 161 (0 ULiège)
Full Text
Peer Reviewed
See detailMapping Magnetic Near-Field Distributions of Plasmonic Nanoantennas
Denkova, D; Verellen, N; Silhanek, Alejandro ULiege et al

in ACS Nano (2013)

We present direct experimental mapping of the lateral magnetic near-field distribution in plasmonic nanoantennas using aperture scanning nearfield optical microscopy (SNOM). By means of full-field ... [more ▼]

We present direct experimental mapping of the lateral magnetic near-field distribution in plasmonic nanoantennas using aperture scanning nearfield optical microscopy (SNOM). By means of full-field simulations it is demonstrated how the coupling of the hollow-pyramid aperture probe to the nanoantenna induces an effective magnetic dipole which efficiently excites surface plasmon resonances only at lateral magnetic field maxima. This excitation in turn affects the detected light intensity enabling the visualization of the lateral magnetic near-field distribution of multiple odd and even order plasmon modes with subwavelength spatial resolution. [less ▲]

Detailed reference viewed: 58 (9 ULiège)
Full Text
Peer Reviewed
See detailElectroresistance Effect in Ferroelectric Tunnel Junctions with Symmetric Electrodes
Bilc, Daniel ULiege; Novaes, F. D.; Iniguez, J. et al

in ACS Nano (2012), 6(2), 1473-1478

Understanding the effects that govern electronic transport in ferroelectric tunnel junctions (FTJs) is of vital importance to improve the efficiency of devices such as ferroelectric memories with ... [more ▼]

Understanding the effects that govern electronic transport in ferroelectric tunnel junctions (FTJs) is of vital importance to improve the efficiency of devices such as ferroelectric memories with nondestructive readout. However, our current knowledge (typically based on simple semiempirical models or first-principles calculations restricted to the limit of zero bias) remains partial, which may hinder the development of more efficient systems. For example, nowadays it is commonly believed that the tunnel electroresistance (TER) effect exploited in such devices mandatorily requires, to be sizable, the use of two different electrodes, with related potential drawbacks concerning retention time, switching, and polarization imprint. In contrast, here we demonstrate at the first-principles level that large TER values of about 200% can be achieved under finite bias in a prototypical FTJ with symmetric electrodes. Our atomistic approach allows us to quantify the contribution of different microscopic mechanisms to the electroresistance, revealing the dominant role of the inverse piezoelectric response of the ferroelectric. On the basis of our analysis, we provide a critical discussion of the semiempirical models traditionally used to describe FTJs. [less ▲]

Detailed reference viewed: 32 (2 ULiège)
Full Text
Peer Reviewed
See detailAluminum Conducts Better than Copper at the Atomic Scale: A First-Principles Study of Metallic Atomic Wires
Simbeck, Adam J.; Lanzillo, Nick; Kharche, Neerav et al

in ACS Nano (2012)

Detailed reference viewed: 34 (1 ULiège)
Full Text
Peer Reviewed
See detailPlasmons Reveal the Direction of Magnetization in Nickel Nanostructures
Valev, Ventsislav K; Silhanek, Alejandro ULiege; Gillijns, Werner et al

in ACS Nano (2011), 5(1), 91-96

We have applied the surface sensitive nonlinear optical technique of magnetization induced second harmonic generation. (MSHG) to plasmonic, magnetic nanostructures made of Ni. We show that surface plasmon ... [more ▼]

We have applied the surface sensitive nonlinear optical technique of magnetization induced second harmonic generation. (MSHG) to plasmonic, magnetic nanostructures made of Ni. We show that surface plasmon contributions to the MSHG signal can reveal the direction of the magnetization. Both the plasmonic and the magnetic nonlinear optical responses can be tuned; our results indicate novel ways to combine nanophotonics, nanoelectronics, and nanomagnetics and suggest the possibility for large magneto-chiral effects in metamaterials. [less ▲]

Detailed reference viewed: 22 (3 ULiège)
Full Text
Peer Reviewed
See detailGas Sensing with Au-Decorated Carbon Nanotubes
Zanolli, Zeila ULiege; Leghrib, Radouane; Felten, Alexandre et al

in ACS Nano (2011), 5(6), 4592-4599

The sensing properties of carbon nanotubes (CNTs) decorated with gold nanopar- ticles have been investigated by means of combined theoretical and experimental approaches. On one hand, first-principles and ... [more ▼]

The sensing properties of carbon nanotubes (CNTs) decorated with gold nanopar- ticles have been investigated by means of combined theoretical and experimental approaches. On one hand, first-principles and nonequilibrium Green's functions techniques give access to the microscopic features of the sensing mechanisms in individual nanotubes, such as electronic charge transfers and quantum conductances. On the other hand, drop coating deposition of carbon nanotubes decorated with gold nanoparticles onto sensor substrates and their characterization in the detection of pollutants such as NO2, CO, and C6H6 provide insight into the sensing ability of nanotube mats. Using the present combined approaches, the improvement in the detection of some specific gases (NO2 and CO) using Au-functionalized nanotubes is explained. However, for other gases such as C6H6, the Au nanoparticles do not seem to play a crucial role in the sensing process when compared with pristine CNTs functionalized with oxygen plasma. Indeed, these different situations can be explained by identifying the relationship between the change of resistance (macroscopic feature) and the shift of the Fermi level (microscopic feature) after gas adsorption. The understanding of the sensing ability at the atomic level opens the way to design new gas sensors and to tune their selectivity by predicting the nature of the metal that is the most appropriate to detect specific molecular species. [less ▲]

Detailed reference viewed: 47 (6 ULiège)
Full Text
Peer Reviewed
See detailQuantum Spin Transport in Carbon Chains
Zanolli, Zeila ULiege; Onida, Giovanni; Charlier, Jean-Christophe

in ACS Nano (2010), 4(9), 5174-5180

First-principles and non-equilibrium Green’s function approaches are used to predict spin-polarized electronic transport in monatomic carbon chains covalently connected to graphene nanoribbons, as ... [more ▼]

First-principles and non-equilibrium Green’s function approaches are used to predict spin-polarized electronic transport in monatomic carbon chains covalently connected to graphene nanoribbons, as recently synthetized experimentally (Jin, C.; et al. Phys. Rev. Lett. 2009, 102, 205501−205504). Quantum electron conductances exhibit narrow resonant states resulting from the simultaneous presence of open conductance channels in the contact region and on the chain atoms. Odd-numbered chains, which acquire metallic or semiconducting character depending on the nature of the edge at the graphene contact, always display a net spin polarization. The combination of electrical and magnetic properties of chains and contacts results in nanodevices with intriguing spintronic properties such as the coexistence of magnetic and semiconducting behaviors. [less ▲]

Detailed reference viewed: 21 (1 ULiège)