We compare the morphology and optical response of plasmonic nanostructures produced by pulsed laser deposition, consisting of a 2D distribution of Ag nanoparticles exposed to air or buried under an amorphous Al 2 O 3 layer whose thickness is tuned in the 0.5 to 14 nm range. We observe that the covering process leads to drastic changes in Ag content, which are interpreted in terms of sputtering of Ag atoms promoted by the incoming Al ions. This Ag sputtering process is avoided as soon as the nanoparticles are embedded under a subnanometer-thick layer of amorphous Al 2 O 3 . Meanwhile, the spectral position of the nanoparticles' characteristic surface plasmon resonance, measured immediately after the film growth, is not significantly affected by the deposition of the covering layer. Nevertheless, the resonance band associated with uncovered Ag nanoparticles has vanished after 12 months, as a result of their oxidation. Embedding the nanoparticles under a subnanometer-thick layer of amorphous Al 2 O 3 is enough to avoid the observed atmospheric aging processes as well as to preserve the features of their surface plasmon resonance. The results presented here are therefore promising in view of the pulsed laser deposition-based elaboration, at the wafer scale, of robust and stable tailor-made plasmonic substrates that may potentially present high electromagnetic coupling with their environment due to the very small distance to the nanostructure surface.

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Influence of excited state spatial distributions on plasma diagnostics: Atmospheric pressure laser-induced He-H2 plasma J. Appl. Phys. 112, 083302 (2012) Characterizing the energy distribution of laser-generated relativistic electrons in cone-wire targets Phys. Plasmas 19, 103108 (2012) Verification of the physical mechanism of THz generation by dual-color ultrashort laser pulses Appl. Phys. Lett. 101, 161104 (2012) ORION laser target diagnostics Rev. Sci. Instrum. 83, 10D732 (2012) Target normal sheath acceleration sheath fields for arbitrary electron energy distribution Phys. Plasmas 19, 083115 (2012) Additional information on J. Appl. Phys. This work reports the study of ion dynamics produced by ablation of Al, Cu, Ag, Au, and Bi targets using nanosecond laser pulses at 193 nm as a function of the laser fluence from threshold up to 15 J cm À2 . An electrical (Langmuir) probe has been used for determining the ion yield as well as kinetic energy distributions. The results clearly evidence that ablation of Al shows unique features when compared to other metals. The ion yield both at threshold (except for Al, which shows a two-threshold-like behavior) and for a fixed fluence above threshold scale approximately with melting temperature of the metal. Comparison of the magnitude of the yield reported in literature using other wavelengths allows us to conclude its dependence with wavelength is not significant. The evolution of the ion yield with fluence becomes slower for fluences above 4-5 J cm À2 with no indication of saturation suggesting that ionization processes in the plasma are still active up to 15 J cm À2 and production of multiple-charged ions are promoted. This dependence is mirrored in the proportion of ions with kinetic energies higher than 200 eV. This proportion is not significant around threshold fluence for all metals except for Al, which is already 20%. The unique features of Al are discussed in terms of the energy of laser photons (6.4 eV) that is enough to induce direct photoionization from the ground state only in the case of this metal.

El acceso a la versión del editor puede requerir la suscripción del recurso Access to the published version may require subscription On the other hand, it is still necessary to understand the role of the growth parameters to produce kesterite material with the optimum properties for maximum device efficiency. fabricated by a sequential, or two-stage, process: deposition of precursor followed by post-sulfurization/selenization. This is advantageous due to its capability and high throughput. However, it is also desirable to reduce the number of stages during the growth process.

Introducing a small dose of an electrolyte additive into solid polymer electrolytes (SPEs) is an appealing strategy for improving the quality of the solid–electrolyte–interphase (SEI) layer formed on the lithium metal (Li°) anode, thereby extending the cycling life of solid-state lithium metal batteries (SSLMBs). In this work, we report a new type of SPEs comprising a low-cost, fluorine-free salt, lithium tricyanomethanide, as the main conducting salt and a fluorinated salt, lithium bis­(fluorosulfonyl)­imide (LiFSI), as the electrolyte additive for enhancing the performance of SPE-based SSLMBs. Our results demonstrate that a homogeneous and stable SEI layer is readily formed on the surface of the Li° electrode through the preferential reductive decomposition of LiFSI, and consequently, the cycle stabilities of Li°||Li° and Li°||LiFePO4 cells are significantly improved after the incorporation of LiFSI as an additive. The intriguing chemistry of the salt anion revealed in this work may expedite the large-scale implementation of SSLMBs in the near future.

We demonstrate that 2D distributions of non-spherical near-coalescence silver nanoparticles (NPs) embedded in an ultrathin dielectric film can be reorganized, shaped and aligned by exposure to ultrashort laser pulses. As-grown samples prepared by pulsed laser deposition show a broad absorption band with a surface plasmon resonance (SPR) at 650 nm, which can be blue-shifted down to 440 nm and transformed to show polarization anisotropy. In situ white light probing of the spectral sample transmission allows control during irradiation of the position and polarization anisotropy of the SPR, effectively controlling particle reorganization and shaping. Using the high spatial resolution of the optical probe technique (better than 10 μm), the dependence of the nanoparticle shape and distribution on the local fluence can be studied in a single irradiated region. The results inferred from the spectral measurements have been confirmed by TEM studies, showing the formation of nanoparticles with prolate shape, preferential alignment along the polarization axis of the laser and a narrow size distribution. This simple and efficient approach for NP shaping and the straightforward extension to multilayer systems offer excellent perspectives for optical encoding, multidimensional data storage and fabrication of complex, polarization-sensitive spectral masks starting from thin films with near-coalescence distributions of NPs.

The abundance of the available sodium sources has led to rapid progress in sodium-ion batteries (SIBs), making them potential candidates for immediate replacement of lithium-ion batteries (LIBs). However, commercialization of SIBs has been hampered by their fading efficiency due to the sodium consumed in the formation of solid−electrolyte interphase (SEI) when using hard carbon (HC) anodes. Herein, Na 2 C 3 O 5 sodium salt is introduced as a highly efficient, cost-effective, and safe cathode sodiation additive. This sustainable sodium salt has an oxidation potential of ∼4.0 V vs Na + /Na°, so it could be practically implemented into SIBs. Moreover, for the first time, we have also revealed by X-ray photoelectron spectroscopy (XPS) that in addition to the compensating Na + ions spent in the SEI layer, the high specific capacity and capacity retention observed from electrochemical measurements are due to the formation of a thinner and more stable cathode−electrolyte interphase (CEI) on the P2−Na 2/3 Mn 0.8 Fe 0.1 Ti 0.1 O 2 while using such a cathode sodiation additive. Half-cell studies with P2−Na 2/3 Mn 0.8 Fe 0.1 Ti 0.1 O 2 cathodes show a 27% increase in the specific capacity (164 mAh g P2 −1 ) with cathode sodiation additives. Full-cell studies with the HC anode show a 4 times increase in the specific capacity of P2−Na 2/3 Mn 0.8 Fe 0.1 Ti 0.1 O 2 . This work provides notable insights into and avenues toward the development of SIBs.

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