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Nanomaterials, Volume 8, Issue 7 (July 2018)

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Open AccessArticle Subwavelength Nanostructuring of Gold Films by Apertureless Scanning Probe Lithography Assisted by a Femtosecond Fiber Laser Oscillator
Nanomaterials 2018, 8(7), 536; https://doi.org/10.3390/nano8070536
Received: 5 June 2018 / Revised: 10 July 2018 / Accepted: 11 July 2018 / Published: 16 July 2018
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Abstract
Optical methods in nanolithography have been traditionally limited by Abbe’s diffraction limit. One method able to overcome this barrier is apertureless scanning probe lithography assisted by laser. This technique has demonstrated surface nanostructuring below the diffraction limit. In this study, we demonstrate how
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Optical methods in nanolithography have been traditionally limited by Abbe’s diffraction limit. One method able to overcome this barrier is apertureless scanning probe lithography assisted by laser. This technique has demonstrated surface nanostructuring below the diffraction limit. In this study, we demonstrate how a femtosecond Yb-doped fiber laser oscillator running at high repetition rate of 46 MHz and a pulse duration of 150 fs can serve as the laser source for near-field nanolithography. Subwavelength features were generated on the surface of gold films down to a linewidth of 10 nm. The near-field enhancement in this apertureless scanning probe lithography setup could be determined experimentally for the first time. Simulations were in good agreement with the experiments. This result supports near-field tip-enhancement as the major physical mechanisms responsible for the nanostructuring. Full article
(This article belongs to the Special Issue Laser-Based Nano Fabrication and Nano Lithography)
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Open AccessArticle Nanostructure Formation on Diamond-Like Carbon Films Induced with Few-Cycle Laser Pulses at Low Fluence from a Ti:Sapphire Laser Oscillator
Nanomaterials 2018, 8(7), 535; https://doi.org/10.3390/nano8070535
Received: 2 June 2018 / Revised: 13 July 2018 / Accepted: 14 July 2018 / Published: 16 July 2018
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Abstract
This study reports the results of experiments on periodic nanostructure formation on diamond-like carbon (DLC) films induced with 800 nm, 7-femtosecond (fs) laser pulses at low fluence from a Ti:sapphire laser oscillator. It was demonstrated that 7-fs laser pulses with a high power
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This study reports the results of experiments on periodic nanostructure formation on diamond-like carbon (DLC) films induced with 800 nm, 7-femtosecond (fs) laser pulses at low fluence from a Ti:sapphire laser oscillator. It was demonstrated that 7-fs laser pulses with a high power density of 0.8–2 TW/cm2 at a low fluence of 5–12 mJ/cm2 can form a periodic nanostructure with a period of 60–80 nm on DLC films. The period decreases with increasing fluence of the laser pulses. The experimental results and calculations for a model target show that 7-fs pulses can produce a thinner metal-like layer on the DLC film through a nonlinear optical absorption process compared with that produced with 100-fs pulses, creating a finer nanostructure via plasmonic near-field ablation. Full article
(This article belongs to the Special Issue Laser-Based Nano Fabrication and Nano Lithography)
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Open AccessArticle Extended Near-Infrared Photoactivity of Bi6Fe1.9Co0.1Ti3O18 by Upconversion Nanoparticles
Nanomaterials 2018, 8(7), 534; https://doi.org/10.3390/nano8070534
Received: 20 June 2018 / Revised: 7 July 2018 / Accepted: 10 July 2018 / Published: 16 July 2018
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Abstract
Bi6Fe1.9Co0.1Ti3O18 (BFCTO)/NaGdF4:Yb3+, Er3+ (NGF) nanohybrids were successively synthesized by the hydrothermal process followed by anassembly method, and BFCTO-1.0/NGF nanosheets, BFCTO-1.5/NGF nanoplates and BFCTO-2.0/NGF truncated tetragonal bipyramids were obtained when
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Bi6Fe1.9Co0.1Ti3O18 (BFCTO)/NaGdF4:Yb3+, Er3+ (NGF) nanohybrids were successively synthesized by the hydrothermal process followed by anassembly method, and BFCTO-1.0/NGF nanosheets, BFCTO-1.5/NGF nanoplates and BFCTO-2.0/NGF truncated tetragonal bipyramids were obtained when 1.0, 1.5 and 2.0 M NaOH were adopted, respectively. Under the irradiation of 980 nm light, all the BFCTO samples exhibited no activity in degrading Rhodamine B (RhB). In contrast, with the loading of NGF upconversion nanoparticles, all the BFCTO/NGF samples exhibited extended near-infrared photoactivity, with BFCTO-1.5/NGF showing the best photocatalytic activity, which could be attributed to the effect of {001} and {117} crystal facets with the optimal ratio. In addition, the ferromagnetic properties of the BFCTO/NGF samples indicated their potential as novel, recyclable and efficient near-infrared (NIR) light-driven photocatalysts. Full article
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Open AccessArticle A Novel Radiation Method for Preparing MnO2/BC Monolith Hybrids with Outstanding Supercapacitance Performance
Nanomaterials 2018, 8(7), 533; https://doi.org/10.3390/nano8070533
Received: 7 June 2018 / Revised: 6 July 2018 / Accepted: 7 July 2018 / Published: 14 July 2018
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Abstract
A novel facile process for fabrication of amorphous MnO2/bamboo charcoal monolith hybrids (MnO2/BC) for potential supercapacitor applications using γ-irradiation methods is described. The structural, morphological and electrochemical properties of the MnO2/BC hybrids have been investigated using X-ray
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A novel facile process for fabrication of amorphous MnO2/bamboo charcoal monolith hybrids (MnO2/BC) for potential supercapacitor applications using γ-irradiation methods is described. The structural, morphological and electrochemical properties of the MnO2/BC hybrids have been investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS) techniques. The combination of BC (electrical double layer charge) and MnO2 (pseudocapacitance) created a complementary effect, which enhanced the specific capacitance and good cyclic stability of the MnO2/BC hybrid electrodes. The MnO2/BC hybrids showed a higher specific capacitance (449 F g−1 at the constant current density of 0.5 A g−1 over the potential range from –0.2 V to 0.8 V), compared with BC (101 F g−1) in 1 M of Na2SO4 aqueous electrolyte. Furthermore, the MnO2/BC hybrid electrodes showed superior cycling stability with 78% capacitance retention, even after 10,000 cycles. The experimental results demonstrated that the high performance of MnO2/BC hybrids could be a potential electrode material for supercapacitors. Full article
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Open AccessArticle Effect of Tb-doped Concentration Variation on the Electrical and Dielectric Properties of CaF2 Nanoparticles
Nanomaterials 2018, 8(7), 532; https://doi.org/10.3390/nano8070532
Received: 29 June 2018 / Revised: 11 July 2018 / Accepted: 12 July 2018 / Published: 14 July 2018
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Abstract
Calcium fluoride (CaF2) nanoparticles with various terbium (Tb) doping concentrations were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), and alternating current (AC) impedance measurement. The original shape and structure of CaF2 nanoparticles were retained after doping. In all
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Calcium fluoride (CaF2) nanoparticles with various terbium (Tb) doping concentrations were investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), and alternating current (AC) impedance measurement. The original shape and structure of CaF2 nanoparticles were retained after doping. In all the samples, the dominant charge carriers were electrons, and the F ion transference number increased with increasing Tb concentration. The defects in the grain region considerably contributed to the electron transportation process. When the Tb concentration was less than 3%, the effect of the ionic radius variation dominated and led to the diffusion of the F ions and facilitated electron transportation. When the Tb concentration was greater than 3%, the increasing deformation potential scattering dominated, impeding F ion diffusion and electron transportation. The substitution of Ca2+ by Tb3+ enables the electron and ion hopping in CaF2 nanocrystals, resulting in increased permittivity. Full article
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Open AccessArticle Thermal and Guest-Assisted Structural Transition in the NH2-MIL-53(Al) Metal Organic Framework: A Molecular Dynamics Simulation Investigation
Nanomaterials 2018, 8(7), 531; https://doi.org/10.3390/nano8070531
Received: 21 June 2018 / Revised: 8 July 2018 / Accepted: 12 July 2018 / Published: 14 July 2018
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Abstract
Reversible structural transition between the Large (LP) and Narrow Pore (NP) forms (breathing phenomena) of the MIL-53(X, X = Al, Cr, Fe, Ga) Metal Organic Framework (MOF) is probably one of the most amazing physical properties of this class of soft-porous materials. Whereas
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Reversible structural transition between the Large (LP) and Narrow Pore (NP) forms (breathing phenomena) of the MIL-53(X, X = Al, Cr, Fe, Ga) Metal Organic Framework (MOF) is probably one of the most amazing physical properties of this class of soft-porous materials. Whereas great attention has been paid to the elucidation of the physical mechanism ruling this reversible transition, the effect of the functionalization on the flexibility has been less explored. Among functionalized MIL-53(Al) materials, the case of NH2-MIL-53(Al) is undoubtedly a very intriguing structural transition rarely observed, and the steadier phase corresponds to the narrow pore form. In this work, the flexibility of the NH2-MIL-53(Al) metal organic framework was investigated by means of molecular dynamics simulations. Guest (methanol) and thermal breathing of the NH2-MIL-53(Al) was thus explored. We show that it is possible to trigger a reversible transition between NP and LP forms upon adsorption, and we highlight the existence of stable intermediate forms and a very large pore phase. Furthermore, the NP form is found thermodynamically stable from 240 to 400 K, which is the result of strong intramolecular hydrogen bonds. Full article
(This article belongs to the Special Issue Thermo-Mechanical Properties of Metal Organic Frameworks)
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Open AccessArticle Characterization and Applications of Nanoparticles Modified in-Flight with Silica or Silica-Organic Coatings
Nanomaterials 2018, 8(7), 530; https://doi.org/10.3390/nano8070530
Received: 29 June 2018 / Revised: 11 July 2018 / Accepted: 11 July 2018 / Published: 14 July 2018
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Abstract
Nanoparticles are coated in-flight with a plasma-enhanced chemical vapor deposition (PECVD) process at ambient or elevated temperatures (up to 300 °C). Two silicon precursors, tetraethyl orthosilicate (TEOS) and hexamethyldisiloxane (HMDSO), are used to produce inorganic silica or silica-organic shells on Pt, Au and
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Nanoparticles are coated in-flight with a plasma-enhanced chemical vapor deposition (PECVD) process at ambient or elevated temperatures (up to 300 °C). Two silicon precursors, tetraethyl orthosilicate (TEOS) and hexamethyldisiloxane (HMDSO), are used to produce inorganic silica or silica-organic shells on Pt, Au and TiO2 particles. The morphology of the coated particles is examined with transmission electron microscopy (TEM) and the chemical composition is studied with Fourier-transform infrared spectroscopy (FTIR), Energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). It is found that both the precursor and certain core materials have an influence on the coating composition, while other parameters, such as the precursor concentration, aerosol residence time and temperature, influence the morphology, but hardly the chemical composition. The coated particles are used to demonstrate simple applications, such as the modification of the surface wettability of powders and the improvement or hampering of the photocatalytic activity of titania particles. Full article
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Open AccessFeature PaperArticle Spontaneous Shape Alteration and Size Separation of Surfactant-Free Silver Particles Synthesized by Laser Ablation in Acetone during Long-Period Storage
Nanomaterials 2018, 8(7), 529; https://doi.org/10.3390/nano8070529
Received: 5 July 2018 / Accepted: 11 July 2018 / Published: 13 July 2018
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Abstract
The technique of laser ablation in liquids (LAL) has already demonstrated its flexibility and capability for the synthesis of a large variety of surfactant-free nanomaterials with a high purity. However, high purity can cause trouble for nanomaterial synthesis, because active high-purity particles can
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The technique of laser ablation in liquids (LAL) has already demonstrated its flexibility and capability for the synthesis of a large variety of surfactant-free nanomaterials with a high purity. However, high purity can cause trouble for nanomaterial synthesis, because active high-purity particles can spontaneously grow into different nanocrystals, which makes it difficult to accurately tailor the size and shape of the synthesized nanomaterials. Therefore, a series of questions arise with regards to whether particle growth occurs during colloid storage, how large the particle size increases to, and into which shape the particles evolve. To obtain answers to these questions, here, Ag particles that are synthesized by femtosecond (fs) laser ablation of Ag in acetone are used as precursors to witness the spontaneous growth behavior of the LAL-generated surfactant-free Ag dots (2–10 nm) into different polygonal particles (5–50 nm), and the spontaneous size separation phenomenon by the carbon-encapsulation induced precipitation of large particles, after six months of colloid storage. The colloids obtained by LAL at a higher power (600 mW) possess a greater ability and higher efficiency to yield colloids with sizes of <40 nm than the colloids obtained at lower power (300 mW), because of the generation of a larger amount of carbon ‘captors’ by the decomposition of acetone and the stronger particle fragmentation. Both the size increase and the shape alteration lead to a redshift of the surface plasmon resonance (SPR) band of the Ag colloid from 404 nm to 414 nm, after storage. The Fourier transform infrared spectroscopy (FTIR) analysis shows that the Ag particles are conjugated with COO– and OH– groups, both of which may lead to the growth of polygonal particles. The CO and CO2 molecules are adsorbed on the particle surfaces to form Ag(CO)x and Ag(CO2)x complexes. Complementary nanosecond LAL experiments confirmed that the particle growth was inherent to LAL in acetone, and independent of pulse duration, although some differences in the final particle sizes were observed. The nanosecond-LAL yields monomodal colloids, whereas the size-separated, initially bimodal colloids from the fs-LAL provide a higher fraction of very small particles that are <5 nm. The spontaneous growth of the LAL-generated metallic particles presented in this work should arouse the special attention of academia, especially regarding the detailed discussion on how long the colloids can be preserved for particle characterization and applications, without causing a mismatch between the colloid properties and their performance. The spontaneous size separation phenomenon may help researchers to realize a more reproducible synthesis for small metallic colloids, without concern for the generation of large particles. Full article
(This article belongs to the Special Issue Laser-Based Nano Fabrication and Nano Lithography)
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Open AccessReview Printable Nanomaterials for the Fabrication of High-Performance Supercapacitors
Nanomaterials 2018, 8(7), 528; https://doi.org/10.3390/nano8070528
Received: 31 May 2018 / Revised: 3 July 2018 / Accepted: 10 July 2018 / Published: 13 July 2018
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Abstract
In recent years, supercapacitors are attracting great attention as one kind of electrochemical energy storage device, which have a high power density, a high energy density, fast charging and discharging, and a long cycle life. As a solution processing method, printing technology is
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In recent years, supercapacitors are attracting great attention as one kind of electrochemical energy storage device, which have a high power density, a high energy density, fast charging and discharging, and a long cycle life. As a solution processing method, printing technology is widely used to fabricate supercapacitors. Printable nanomaterials are critical to the fabrication of high-performance supercapacitors by printing technology. In this work, the advantages of printing technology are summarized. Moreover, various nanomaterials used to fabricate supercapacitors by printing technology are presented. Finally, the remaining challenges and broad research as well as application prospects in printing high-performance supercapacitors with nanomaterials are proposed. Full article
(This article belongs to the Special Issue Three-dimensional Nanomaterials for Energy Storage and Conversions)
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Open AccessArticle Single-Walled Carbon Nanotube (SWCNT) Loaded Porous Reticulated Vitreous Carbon (RVC) Electrodes Used in a Capacitive Deionization (CDI) Cell for Effective Desalination
Nanomaterials 2018, 8(7), 527; https://doi.org/10.3390/nano8070527
Received: 7 March 2018 / Revised: 6 June 2018 / Accepted: 3 July 2018 / Published: 13 July 2018
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Abstract
Acid-functionalized single-walled carbon nanotube (a-SWCNT)-coated reticulated vitreous carbon (RVC) composite electrodes have been prepared and the use of these electrodes in capacitive deionization (CDI) cells for water desalination has been the focus of this study. The performance of these electrodes was tested based
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Acid-functionalized single-walled carbon nanotube (a-SWCNT)-coated reticulated vitreous carbon (RVC) composite electrodes have been prepared and the use of these electrodes in capacitive deionization (CDI) cells for water desalination has been the focus of this study. The performance of these electrodes was tested based on the applied voltage, flow rate, bias potential and a-SWCNT loadings, and then evaluated by electrosorption dynamics. The effect of the feed stream directly through the electrodes, between the electrodes, and the distance between the electrodes in the CDI system on the performance of the electrodes has been investigated. The interaction of ions with the electrodes was tested through Langmuir and Freundlich isotherm models. A new CDI cell was developed, which shows an increase of 23.96% in electrosorption capacity compared to the basic CDI cells. Moreover, a comparison of our results with the published results reveals that RVC/a-SWCNT electrodes produce 16 times more pure water compared to the ones produced using only CNT-based electrodes. Finally, it can be inferred that RVC/a-SWCNT composite electrodes in newly-developed CDI cells can be effectively used in desalination technology for water purification. Full article
(This article belongs to the Special Issue Electrochemically Engineering of Nanoporous Materials)
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Open AccessArticle Enhanced Visible Light Driven Photocatalytic Behavior of BiFeO3/Reduced Graphene Oxide Composites
Nanomaterials 2018, 8(7), 526; https://doi.org/10.3390/nano8070526
Received: 26 June 2018 / Revised: 5 July 2018 / Accepted: 9 July 2018 / Published: 13 July 2018
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Abstract
BiFeO3/Reduced Graphene Oxide (BFO/RGO) composites have been fabricated by a simple hydrothermal method. The X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, and X-ray photoelectron spectroscopy (XPS) analysis reveal that graphene oxide was reduced in hydrothermal process and BFO/RGO composites were
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BiFeO3/Reduced Graphene Oxide (BFO/RGO) composites have been fabricated by a simple hydrothermal method. The X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, and X-ray photoelectron spectroscopy (XPS) analysis reveal that graphene oxide was reduced in hydrothermal process and BFO/RGO composites were successfully synthesized. UV-visible absorption and photoluminescence properties show that the introduction of RGO can effectively reduce the recombination of photogenerated electron and hole pairs. Compared to the pristine BFO, the photocatalytic performance of BiFeO3 Graphene Oxide (BGO) composites is enhanced for the degradation of Methylene blue (MB) solution under visible light irradiation, and the result shows that the optimal amount of Graphene Oxide (GO) in the composites is 60 mg (BGO60). The excellent photocatalytic performance is mainly ascribed to improved light absorption, increased reactive sites, and the low recombination rate of electron-hole pairs. This work can provide more insights into designing advanced photocatalysts for wastewater treatment and environmental protection. Full article
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Open AccessArticle Percolated Si:SiO2 Nanocomposites: Oven- vs. Millisecond Laser-Induced Crystallization of SiOx Thin Films
Nanomaterials 2018, 8(7), 525; https://doi.org/10.3390/nano8070525
Received: 1 June 2018 / Revised: 4 July 2018 / Accepted: 10 July 2018 / Published: 13 July 2018
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Abstract
Three-dimensional nanocomposite networks consisting of percolated Si nanowires in a SiO2 matrix, Si:SiO2, were studied. The structures were obtained by reactive ion beam sputter deposition of SiOx (x ≈ 0.6) thin films at 450 C and subsequent crystallization
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Three-dimensional nanocomposite networks consisting of percolated Si nanowires in a SiO2 matrix, Si:SiO2, were studied. The structures were obtained by reactive ion beam sputter deposition of SiOx (x ≈ 0.6) thin films at 450 C and subsequent crystallization using conventional oven, as well as millisecond line focus laser treatment. Rutherford backscattering spectrometry, Raman spectroscopy, X-ray diffraction, cross-sectional and energy-filtered transmission electron microscopy were applied for sample characterization. While oven treatment resulted in a mean Si wire diameter of 10 nm and a crystallinity of 72% within the Si volume, almost single-domain Si structures of 30 nm in diameter and almost free of amorphous Si were obtained by millisecond laser application. The structural differences are attributed to the different crystallization processes: conventional oven tempering proceeds via solid state and millisecond laser application via liquid phase crystallization of Si. The five orders of magnitude larger diffusion constant in the liquid phase is responsible for the three-times larger Si nanostructure diameter. In conclusion, laser treatment offers not only significantly shorter process times, but moreover, a superior structural order of nano-Si compared to conventional heating. Full article
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Open AccessArticle Impact of Nano-Crystalline Diamond Enhanced Hydrophilicity on Cell Proliferation on Machined and SLA Titanium Surfaces: An In-Vivo Study in Rodents
Nanomaterials 2018, 8(7), 524; https://doi.org/10.3390/nano8070524
Received: 3 June 2018 / Revised: 2 July 2018 / Accepted: 4 July 2018 / Published: 13 July 2018
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Abstract
By coating surfaces with nano-crystalline diamond (NCD) particles, hydrophilicity can be altered via sidechain modifications without affecting surface texture. The present study aimed to assess the impact of NCD hydrophilicity on machined and rough SLA titanium discs on soft tissue integration, using a
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By coating surfaces with nano-crystalline diamond (NCD) particles, hydrophilicity can be altered via sidechain modifications without affecting surface texture. The present study aimed to assess the impact of NCD hydrophilicity on machined and rough SLA titanium discs on soft tissue integration, using a rodent model simulating submerged healing. Four different titanium discs (machined titanium = M Titanium, NCD-coated hydrophilic machined titanium = M-O-NCD, sand blasted acid etched (SLA Titanium) titanium, and hydrophilic NCD-coated SLA titanium = SLA O-NCD) were inserted in subdermal pockets of 12 Wistar rats. After one and four weeks of healing, the animals were sacrificed. Biopsies were embedded in methyl methacrylate (MMA), and processed for histology. The number of cells located within a region of interest (ROI) of 10 µm around the discs were counted and compared statistically. Signs of inflammation were evaluated descriptively employing immunohistochemistry. At one week, M-O-NCD coated titanium discs showed significantly higher amounts of cells compared to M Titanium, SLA Titanium, and SLA-O-NCD (p < 0.001). At four weeks, significant higher cell counts were noted at SLA-O-NCD surfaces (p < 0.01). Immunohistochemistry revealed decreased inflammatory responses at hydrophilic surfaces. Within the limits of an animal study, M-O-NCD surfaces seem to stimulate cell proliferation in the initial healing phase, whereas SLA-O-NCD surfaces appeared advantageous afterwards. Full article
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Open AccessFeature PaperArticle Dual THz Wave and X-ray Generation from a Water Film under Femtosecond Laser Excitation
Nanomaterials 2018, 8(7), 523; https://doi.org/10.3390/nano8070523
Received: 25 June 2018 / Revised: 10 July 2018 / Accepted: 11 July 2018 / Published: 13 July 2018
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Abstract
Simultaneous emission of the THz wave and hard X-ray from thin water free-flow was induced by the irradiation of tightly-focused femtosecond laser pulses (35 fs, 800 nm, 500 Hz) in air. Intensity measurements of the THz wave and X-ray were carried out at
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Simultaneous emission of the THz wave and hard X-ray from thin water free-flow was induced by the irradiation of tightly-focused femtosecond laser pulses (35 fs, 800 nm, 500 Hz) in air. Intensity measurements of the THz wave and X-ray were carried out at the same time with time-domain spectroscopy (TDS) based on electro-optic sampling with a ZnTe(110) crystal and a Geiger counter, respectively. Intensity profiles of the THz wave and X-ray emission as a function of the solution flow position along the incident laser axis at the laser focus show that the profile width of the THz wave is broader than that of the X-ray. Furthermore, the profiles of the THz wave measured in reflection and transmission directions show different features and indicate that THz wave emission is, under single-pulse excitation, induced mainly in laser-induced plasma on the water flow surface. Under double-pulse excitation with a time separation of 4.6 ns, 5–10 times enhancements of THz wave emission were observed. Such dual light sources can be used to characterise materials, as well as to reveal the sequence of material modifications under intense laser pulses. Full article
(This article belongs to the Special Issue Laser-Based Nano Fabrication and Nano Lithography)
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Open AccessReview Adsorption Heat Storage: State-of-the-Art and Future Perspectives
Nanomaterials 2018, 8(7), 522; https://doi.org/10.3390/nano8070522
Received: 24 June 2018 / Revised: 4 July 2018 / Accepted: 7 July 2018 / Published: 12 July 2018
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Abstract
Thermal energy storage (TES) is a key technology to enhance the efficiency of energy systems as well as to increase the share of renewable energies. In this context, the present paper reports a literature review of the recent advancement in the field of
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Thermal energy storage (TES) is a key technology to enhance the efficiency of energy systems as well as to increase the share of renewable energies. In this context, the present paper reports a literature review of the recent advancement in the field of adsorption TES systems. After an initial introduction concerning different heat storage technologies, the working principle of the adsorption TES is explained and compared to other technologies. Subsequently, promising features and critical issues at a material, component and system level are deeply analyzed and the ongoing activities to make this technology ready for marketing are introduced. Full article
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