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1.
Sensors (Basel) ; 19(3)2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30764485

RESUMO

We present a novel plasmonic hydrogen sensor consisting of an array of gold nanodisks produced by lithography. The size, height, and spacing of the disks were optimized using finite element simulation to generate a sharp localized surface plasmon resonance peak in the near-infrared wavelength region. The reported results show the possibility of developing an optical gas sensors-based bare Au nanostructures operating at a low temperature.

2.
Materials (Basel) ; 11(3)2018 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-29538338

RESUMO

Sub-monolayers of monodisperse Au colloids with different surface coverage have been embedded in between two different metal oxide thin films, combining sol-gel depositions and proper substrates functionalization processes. The synthetized films were TiO2, ZnO, and NiO. X-ray diffraction shows the crystallinity of all the oxides and verifies the nominal surface coverage of Au colloids. The surface plasmon resonance (SPR) of the metal nanoparticles is affected by both bottom and top oxides: in fact, the SPR peak of Au that is sandwiched between two different oxides is centered between the SPR frequencies of Au sub-monolayers covered with only one oxide, suggesting that Au colloids effectively lay in between the two oxide layers. The desired organization of Au nanoparticles and the morphological structure of the prepared multi-layered structures has been confirmed by Rutherford backscattering spectrometry (RBS), Secondary Ion Mass Spectrometry (SIMS), and Scanning Electron Microscopy (SEM) analyses that show a high quality sandwich structure. The multi-layered structures have been also tested as optical gas sensors.

3.
Opt Lett ; 43(4): 703-706, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29444057

RESUMO

We show how to correctly extract from the ellipsometric data the surface susceptibility and the surface conductivity that describe the optical properties of monolayer MoS2. Theoretically, these parameters stem from modelling a single-layer two-dimensional crystal as a surface current, a truly two-dimensional model. Current experimental practice is to consider this model equivalent to a homogeneous slab with an effective thickness given by the interlayer spacing of the exfoliating bulk material. We prove that the error in the evaluation of the surface susceptibility of monolayer MoS2, owing to the use of the slab model, is at least 10% or greater, a significant discrepancy in the determination of the optical properties of this material.

4.
Mar Environ Res ; 136: 179-189, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29459068

RESUMO

Biochemical and cellular responses to low concentrations of TiO2 nanoparticles (nTiO2, 1 and 10 µg/L) and bulk (bTiO2, 10 µg/L) were evaluated in gills, digestive gland and haemolymph of the clam Ruditapes philippinarum after1, 3 and 7 days' exposure. At 7 days, titanium content was determined in gills and digestive gland. nTiO2 significantly increased antioxidant enzyme activities in both tissues, and lipid peroxidation in digestive gland at 10 µg/L only, and affected glutathione S-transferase activity. Slighter variations were observed in bTiO2-treated clams. A significant Ti bioaccumulation was detected in both gills and digestive gland of 10 µg nTiO2/L-exposed clams. In haemolymph, nTiO2 affected total haemocyte count, haemocyte proliferation, haemocyte diameter and volume, and induced DNA damage. Overall, this study demonstrated that TiO2 alters most of the biomarkers measured in clams, although responses were differently modulated depending on tissues and exposure conditions, and indicated that nTiO2 can be accumulated by bivalves, suggesting a potential risk for filter-feeding animals.


Assuntos
Bivalves/fisiologia , Nanopartículas/toxicidade , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores , Bivalves/efeitos dos fármacos , Brânquias , Nanopartículas/metabolismo , Titânio/metabolismo , Poluentes Químicos da Água/metabolismo
5.
ACS Appl Mater Interfaces ; 10(1): 651-659, 2018 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-29272094

RESUMO

In this study, we report the fabrication of nanocomposites made of titanate nanosheets immobilized in a solid matrix of regenerated silk fibroin as novel heavy-metal-ion removal systems. The capacity of these nanocomposite films to remove lead, mercury, and copper cations from water was investigated, and as shown by the elemental quantitative analysis performed, their removal capacity is 73 mmol/g for all of the ions tested. We demonstrate that the nanocomposites can efficiently retain the adsorbed ions, with no release of titanate nanosheets occurring even after several exposure cycles to ionic solutions, eliminating the risk of release of potentially hazardous nanosubstances to the environment. We also prove that the introduction of sodium ions in the nanocomposite formulation makes the materials highly selective toward the lead ions. The developed biopolymer nanocomposites can be potentially used for the efficient removal of heavy-metal-ion pollutants from water and, thanks to their physical and optical characteristics, offer the possibility to be used in sensor applications.

6.
ACS Appl Mater Interfaces ; 8(44): 30440-30448, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27750418

RESUMO

Highly doped wide band gap metal oxide nanocrystals have recently been proposed as building blocks for applications as transparent electrodes, electrochromics, plasmonics, and optoelectronics in general. Here we demonstrate the application of gallium-doped zinc oxide (GZO) nanocrystals as novel plasmonic and chemiresistive sensors for the detection of hazardous gases including hydrogen (H2) and nitrogen dioxide (NO2). GZO nanocrystals with a tunable surface plasmon resonance in the near-infrared are obtained using a colloidal heat-up synthesis. Thanks to the strong sensitivity of the plasmon resonances to chemical and electrical changes occurring at the surface of the nanocrystals, such optical features can be used to detect the presence of toxic gases. By monitoring the changes in the dopant-induced plasmon resonance in the near-infrared, we demonstrate that GZO thin films prepared depositing an assembly of highly doped GZO colloids are able to optically detect both oxidizing and reducing gases at mild (<100 °C) operating temperatures. Combined optical and electrical measurements show that trivalent dopants within ZnO nanocrystals enhance the gas sensing response compared to undoped ZnO. Moreover, improved sub-ppm of NO2 gas sensitivity is achieved by activating the sensors response through combined purple-blue (λ = 430 nm) light irradiation and mild heating at 75 °C. In addition, these thin films based on degenerately doped semiconductors are highly transparent in the visible range, enabling the fabrication of "invisible" gas sensors. The use of highly doped semiconductive nanocrystals for both IR plasmonic and chemiresistive sensors represent a marked advancement toward the development of highly sensitive and selective devices.

7.
Environ Sci Pollut Res Int ; 23(15): 15275-93, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27102620

RESUMO

Potential nanoparticle (NP) toxicity poses a growing concern in marine coastal environments. Among NPs, zinc oxide nanoparticles (nZnO) are widely used in many common products that ultimately become deposited in coastal habitats from multiple non-point sources. In this study, we evaluated the in vivo effects of nZnO in the clam Ruditapes philippinarum. Animals were exposed to nZnO (1 and 10 µg/L) and ZnCl2 (10 µg/L) for 7 days. ZnCl2 was used to compare the effects of the NPs to those of Zn(2+) and to ascertain whether nZnO toxicity is attributable to the release of ions into the aquatic medium. At differing time intervals during the exposure, several biochemical and cellular responses were evaluated in the clam gills, digestive gland, and haemolymph. The results showed that nZnO, at concentrations close to the predicted environmental levels, significantly affected various parameters in clam tissues. Significant increases in catalase and superoxide dismutase activities and a decreasing trend of glutathione S-transferase activity indicated the involvement of oxidative stress in nZnO toxicity. In clams exposed to ZnCl2, slight variations in antioxidant enzyme activities were detected with respect to nZnO-treated clams. However, no damage to lipids, proteins or DNA was revealed in all exposure conditions, suggesting a protection of antioxidant enzymes in the tissues. Of the various haemolymph parameters measured, haemocyte proliferation increased significantly, in ZnCl2-treated clams in particular. Under nZnO (10 µg/L) and ZnCl2 exposure, DNA damage in haemocytes was also revealed, but it was lower in clams exposed to ZnCl2. A decreasing trend in gill AChE activity of treated clams proposed a possible role of zinc ions in nZnO toxicity. However, the dissimilar modulation of the responses in the nZnO- and ZnCl2-exposed clams suggested different mechanisms of action, with nZnO toxicity possibly depending not only on the release of zinc ions but also on NP-specific features. Changes in the biological parameters measured in the clams were consistent with Zn accumulation in their gills and digestive glands.


Assuntos
Bivalves/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Poluentes Químicos da Água/toxicidade , Óxido de Zinco/toxicidade , Acetilcolinesterase/metabolismo , Animais , Bivalves/metabolismo , Catalase/metabolismo , Proliferação de Células , Cloretos/toxicidade , Fragmentação do DNA , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Glutationa Transferase/metabolismo , Hemolinfa/metabolismo , Peroxidação de Lipídeos , Nanopartículas Metálicas/química , Estresse Oxidativo , Tamanho da Partícula , Carbonilação Proteica , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/química , Compostos de Zinco/toxicidade , Óxido de Zinco/química
8.
Phys Chem Chem Phys ; 18(14): 9586-93, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26996752

RESUMO

We applied cathodoluminescence (CL) spectroscopy to evaluate the defect-induced luminescence within ZnO and Ga-doped ZnO (GZO) nanoparticles. The observed emissions from defect sites present in the GZO lattice exhibited a strong dependence on both dopant content and synthesis methods. The strong and broad defect-induced emissions and inhomogeneous population of intrinsic defects in nano-sized ZnO particles could effectively be suppressed by Ga doping, although large dopant amounts caused the generation of negatively-charged defects, VZn and Oi, with a subsequent increase of the luminescence. Upon deconvolution of the retrieved CL spectra into individual sub-bands, the physical origin of all the sub-bands could be clarified, and related to sample composition and synthesis protocol. This study lays the foundation of quantitative CL evaluation of defects to assess the quality of GZO optoelectronic devices.

9.
ACS Appl Mater Interfaces ; 8(1): 716-25, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26674375

RESUMO

To achieve complete oxidation of ethanol (EOR) to CO2, higher operating temperatures (often called intermediate-T, 150-200 °C) and appropriate catalysts are required. We examine here titanium oxycarbide (hereafter TiOxCy) as a possible alternative to standard carbon-based supports to enhance the stability of the catalyst/support assembly at intermediate-T. To test this material as electrocatalyst support, a systematic study of its behavior under electrochemical conditions was carried out. To have a clear description of the chemical changes of TiOxCy induced by electrochemical polarization of the material, a special setup that allows the combination of X-ray photoelectron spectroscopy and electrochemical measurements was used. Subsequently, an electrochemical study was carried out on TiOxCy powders, both at room temperature and at 150 °C. The present study has revealed that TiOxCy is a sufficiently conductive material whose surface is passivated by a TiO2 film under working conditions, which prevents the full oxidation of the TiOxCy and can thus be considered a stable electrode material for EOR working conditions. This result has also been confirmed through density functional theory (DFT) calculations on a simplified model system. Furthermore, it has been experimentally observed that ethanol molecules adsorb on the TiOxCy surface, inhibiting its oxidation. This result has been confirmed by using in situ Fourier transform infrared spectroscopy (FTIRS). The adsorption of ethanol is expected to favor the EOR in the presence of suitable catalyst nanoparticles supported on TiOxCy.

10.
ACS Appl Mater Interfaces ; 7(45): 25473-8, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26503740

RESUMO

The ability to control chemical reactions using ultrafast light exposure has the potential to dramatically advance materials and their processing toward device integration. In this study, we show how intense pulsed light (IPL) can be used to trigger and modulate the chemical transformations of printed copper oxide features into metallic copper. By varying the energy of the IPL, CuO films deposited from nanocrystal inks can be reduced to metallic Cu via a Cu2O intermediate using single light flashes of 2 ms duration. Moreover, the morphological transformation from isolated Cu nanoparticles to fully sintered Cu films can also be controlled by selecting the appropriate light intensity. The control over such transformations enables for the fabrication of sintered Cu electrodes that show excellent electrical and mechanical properties, good environmental stability, and applications in a variety of flexible devices.

11.
ACS Appl Mater Interfaces ; 7(46): 25685-92, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26517577

RESUMO

Aerosol processing enables the preparation of hierarchical graphene nanocomposites with special crumpled morphology in high yield and in a short time. Using modular insertion of suitable precursors in the starting solution, it is possible to synthesize different types of graphene-based materials ranging from heteroatom-doped graphene nanoballs to hierarchical nanohybrids made up by nitrogen-doped crumpled graphene nanosacks that wrap finely dispersed MoS2 nanoparticles. These materials are carefully investigated by microscopic (SEM, standard and HR TEM), diffraction (grazing incidence X-ray diffraction (GIXRD)) and spectroscopic (high resolution photoemission, Raman and UV-visible spectroscopy) techniques, evidencing that nitrogen dopants provide anchoring sites for MoS2 nanoparticles, whereas crumpling of graphene sheets drastically limits aggregation. The activity of these materials is tested toward the photoelectrochemical production of hydrogen, obtaining that N-doped graphene/MoS2 nanohybrids are seven times more efficient with respect to single MoS2 because of the formation of local p-n MoS2/N-doped graphene nanojunctions, which allow an efficient charge carrier separation.

12.
Adv Mater ; 27(42): 6728-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26414278

RESUMO

The combination of water-based titanate nanosheets dispersion and silk fibroin solution allows the realization of a versatile nanocomposite. Different fabrication techniques can be easily applied on these nanocomposites to manipulate the end form of these materials on the micro- and nanoscale. Easy tunability of the refractive index from n = 1.55 up to n = 1.97 is achieved, making it attractive for flexible, biopolymer-based optical devices.


Assuntos
Fibroínas/química , Microtecnologia/métodos , Nanocompostos/química , Nanoestruturas/química , Nanotecnologia/métodos , Vidro/química , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Microtecnologia/instrumentação , Nanotecnologia/instrumentação , Compostos de Amônio Quaternário/química , Refratometria , Soluções , Titânio , Água/química
13.
Sensors (Basel) ; 15(7): 16910-28, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26184216

RESUMO

Plasmonic gas sensors are optical sensors that use localized surface plasmons or extended surface plasmons as transducing platform. Surface plasmons are very sensitive to dielectric variations of the environment or to electron exchange, and these effects have been exploited for the realization of sensitive gas sensors. In this paper, we review our research work of the last few years on the synthesis and the gas sensing properties of sol-gel based nanomaterials for plasmonic sensors.

14.
ACS Nano ; 9(8): 7846-56, 2015 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-26154166

RESUMO

We used dark field spectroscopy to monitor the dissociation of hydrogen on single gold nanoparticles embedded in metal oxide supports. Individual gold nanorods were monitored in real time to reveal the peak position, the full width at half-maximum, and the relative intensity of the surface plasmon resonances during repeated N2-H2-N2 and air-H2-air cycles. Shifts in the spectra are shown to be due to changes in electron density and not to refractive index shifts in the environment. We demonstrate that hydrogen does not dissociate on gold nanorods (13 nm × 40 nm) at room temperature when in contact with silica and that electrons or hydrogen atoms migrate from Pt nanoparticles to Au nanoparticles through the supporting metal oxide at room temperature. However, this spillover mechanism only occurs for semiconducting oxides (anatase TiO2 and ZnO) and does not occur for Au and Pt nanoparticles embedded in silica. Finally, we show that hydrogen does dissociate directly on anatase surfaces at room temperature during air-H2-air cycles. Our results show that hydrogen spillover, surface dissociation of reactants, and surface migration of chemical intermediates can be detected and monitored in real time at the single particle level.

15.
Mar Environ Res ; 103: 11-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25460057

RESUMO

The continuous growth of nanotechnology and nano-industries, the considerable increase of products containing nanoparticles (NPs) and the potential release of NPs in aquatic environments suggest a need to study NP effects on aquatic organisms. In this context, in vitro assays are commonly used for evaluating or predicting the negative effects of chemicals and for understanding their mechanisms of action. In this study, a physico-chemical characterisation of titanium dioxide NPs (n-TiO2) was performed, and an in vitro approach was used to investigate the effects of n-TiO2 on haemocytes of the clam Ruditapes philippinarum. In particular, the effects on haemocyte phagocytic activity were evaluated in two different experiments (with and without pre-treatment of haemocytes) by exposing cells to P25 n-TiO2 (0, 1 and 10 µg/mL). In addition, the capability of n-TiO2 to interact with clam haemocytes was evaluated with a transmission electron microscope (TEM). In this study, n-TiO2 particles showed a mean diameter of approximately 21 nm, and both anatase (70%) and rutile (30%) phases were revealed. In both experiments, n-TiO2 significantly decreased the phagocytic index compared with the control, suggesting that NPs are able to interfere with cell functions. The results of the TEM analysis support this hypothesis. Indeed, we observed that TiO2 NPs interact with cell membranes and enter haemocyte cytoplasm and vacuoles after 60 min of exposure. To the best of our knowledge, this is the first study demonstrating the internalisation of TiO2 NPs into R. philippinarum haemocytes. The present study can contribute to the understanding of the mechanisms of action of TiO2 NPs in bivalve molluscs, at least at the haemocyte level.


Assuntos
Bivalves/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Fagocitose/efeitos dos fármacos , Titânio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Hemócitos/efeitos dos fármacos , Microscopia Eletrônica de Transmissão , Tamanho da Partícula
16.
Sensors (Basel) ; 14(7): 11427-43, 2014 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-24977386

RESUMO

Thin films of tungsten trioxide were deposited on quartz substrates by RF magnetron sputtering. Different annealing temperatures in the range from 423 to 973 K were used under ambient atmosphere. The influence of the annealing temperature on the structure and optical properties of the resulting WO3 thin films were studied. The surface morphology of the films is composed of grains with an average size near 70 nm for the films annealed between 773 and 973 K. Some of the WO3 thin films were also coated with Pt nanoparticles of about 45 nm in size. Spectrometric measurements of transmittance were carried out for both types of WO3 samples in the wavelength range from 200-900 nm, to determine the effect of the exposure to two different gases namely H2 and CO. Films showed fast response and recovery times, in the range of few seconds. The addition of Pt nanoparticles enables reducing the operation temperature to room temperature.


Assuntos
Gases/análise , Membranas Artificiais , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Óxidos/química , Platina/química , Análise Espectral/instrumentação , Tungstênio/química , Desenho de Equipamento , Análise de Falha de Equipamento , Gases/química , Tamanho da Partícula , Transdutores
17.
ACS Appl Mater Interfaces ; 6(10): 7773-81, 2014 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-24750118

RESUMO

We report the achievement of sensitive gas detection using periodic silver nanoprisms fabricated by a simple and low-cost lithographic technique. The presence of sharp tips combined with the periodic arrangement of the nanoprisms allowed the excitement of isolated and interacting localized surface plasmon resonances. Specific sensing capabilities with respect to aromatic hydrocarbons were achieved when the metal nanoprism arrays were coupled in the near field with functional hybrid films, providing a real-time, label-free, and reversible methodology. Ultra-high-vacuum temperature-programmed desorption measurements demonstrated an interaction energy between the sensitive film and analytes in the range of 55-71 kJ/mol. The far-field optical properties and the detection sensitivity of the sensors, modeled using a finite element method, were correlated to experimental data from gas sensing tests. An absorbance variation of 1.2% could be observed and associated with a theoretical increase in the functional film refractive index of ∼0.001, as a consequence to the interaction with 30 ppm xylene. The possibility of detecting such a small variation in the refractive index suggests the highly promising sensing capabilities of the presented technique.

18.
Nanoscale ; 6(3): 1560-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24322302

RESUMO

The preparation of palladium alloy nanoparticles is of great interest for many applications, especially in catalysis. Starting from presynthesized nanoparticles of a less noble metal, a transmetallation reaction involving a redox process at the nanoparticle surface can be exploited to modify the nanoparticle composition and crystalline phase. As an example, monodispersed ε-cobalt and face-centered cubic copper nanoparticles were synthesized in organic solvents at high temperature and the as-formed nanoparticles were reacted with palladium(ii) hexafluoroacetylacetonate resulting in the formation of alloyed nanoparticles whose composition closely follows the reactant ratio. The oxidative state of the nanoparticle surface greatly affects the success of the transmetallation reaction and a reduction treatment was necessary to achieve the desired final product. Electron microscopy and X-ray diffraction showed that for cobalt a limiting palladium content for the ε-phase alloy is found, above which an fcc alloy nucleates, while for copper the fcc crystalline phase is preserved throughout the whole composition range.

19.
J Am Chem Soc ; 135(9): 3439-48, 2013 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-23394063

RESUMO

We present a new colloidal synthesis of gallium-doped zinc oxide nanocrystals that are transparent in the visible and absorb in the near-infrared. Thermal decomposition of zinc stearate and gallium nitrate after hot injection of the precursors in a mixture of organic amines leads to nanocrystals with tunable properties according to gallium amount. Substitutional Ga(3+) ions trigger a plasmonic resonance in the infrared region resulting from an increase in the free electrons concentration. These nanocrystals can be deposited by spin coating, drop casting, and spray coating resulting in homogeneous and high-quality thin films. The optical transmission of the Ga-ZnO nanoparticle assemblies in the visible is greater than 90%, and at the same time, the near-infrared absorption of the nanocrystals is maintained in the films as well. Several strategies to improve the films electrical and optical properties have been presented, such as UV treatments to remove the organic compounds responsible for the observed interparticle resistance and reducing atmosphere treatments on both colloidal solutions and thin films to increase the free carriers concentration, enhancing electrical conductivity and infrared absorption. The electrical resistance of the nanoparticle assemblies is about 30 kΩ/sq for the as-deposited, UV-exposed films, and it drops down to 300 Ω/sq after annealing in forming gas at 450 °C, comparable with state of the art tin-doped indium oxide coatings deposited from nanocrystal inks.


Assuntos
Gálio/química , Tinta , Temperatura , Óxido de Zinco/química , Coloides/química , Tamanho da Partícula , Propriedades de Superfície
20.
Nanoscale ; 4(19): 5972-9, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22907103

RESUMO

Metal (Au, Pt, Au@Pt) and metal oxide (TiO(2)) nanoparticles are synthesized with colloidal techniques and subsequently used as nanocrystal inks for thin films deposition. The optical properties of Au colloids are strongly influenced by both Pt and TiO(2) interfaces: while platinum causes a damping and a blue-shift of the Au Surface Plasmon Resonance (SPR) peak as a consequence of the metal-metal interaction, the anatase matrix is responsible for the red shift of the plasmon frequency due to the increased refractive index. By a careful tailoring of the nanoparticles synthesis, high quality, scattering-free films composed of an anatase matrix embedding Au, Pt and Au@Pt colloids are deposited at room temperature and stabilized at 200 °C. Room temperature exposure of these films to hydrogen leads to optical changes. In the case of Au, there is a slow blue shift of the surface plasmon band, resulting in a wavelength dependent optical response. Much faster but smaller optical changes occur for titania films containing Pt. When both metals are present, the optical response of the gold is much faster. This is attributed to spillover of hydrogen atoms from platinum to gold. This synergy enables enhanced optical sensing of hydrogen at room temperature by combining the low temperature dissociation of H(2) on Pt with the intensive surface plasmon response of the gold nanocrystals.


Assuntos
Ouro/química , Hidrogênio/análise , Platina/química , Ressonância de Plasmônio de Superfície , Titânio/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Temperatura
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