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1.
Small ; 20(29): e2311289, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38349036

RESUMO

Hydrogen evolution reaction (HER) in neutral or alkaline electrolytes is appealing for sustainable hydrogen production driven by water splitting, but generally suffers from unsatisfied catalytic activities at high current densities owing to extra kinetic energy barriers required to generate protons through water dissociation. In response, here, a competitive Ni3N/Co3N/CoP electrocatalyst with multifunctional interfacial sites and multilevel interfaces, in which Ni3N/CoP performs as active sites to boost initial water dissociation and Co3N/CoP accelerates subsequent hydrogen adsorption process as confirmed by density functional theory calculations and in situ X-ray photoelectron spectroscopy analysis, is reported. This hybrid catalyst possesses extraordinary HER activity in base, featured by extremely low overpotentials of 115 and 142 mV to afford 500 and 1000 mA cm-2, respectively, outperforming most ever-reported metal phosphides-based catalysts. This catalyst presents an ultrahigh current density of 3545 mA cm-2 by a factor of 4.96 relative to noble Pt/C catalysts (715 mA cm-2) at 0.2 V. Assembled with Fe(PO3)2/Ni2P anode, industrial-level current densities of 500/1000 mA cm-2 at ultralow cell voltages of 1.62/1.66 V for overall water electrolysis with outstanding long-term stability are actualized. More interestingly, this hybrid catalyst also performs well in acidic, neutral freshwater, and seawater requiring relatively low overpotentials of 140, 290, and 331 mV to reach 500 mA cm-2. Particularly, this catalyst can withstand electrochemical corrosion without obvious activity decay at the industrial-level current densities for over 100 h in base. This work provides a cornerstone for the construction of advanced catalysts operated in different pH environments.

2.
Small ; 20(29): e2400564, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38368264

RESUMO

Developing efficient metal-free catalysts to directly synthesize hydrogen peroxide (H2O2) through a 2-electron (2e) oxygen reduction reaction (ORR) is crucial for substituting the traditional energy-intensive anthraquinone process. Here, in-plane topological defects enriched graphene with pentagon-S and pyrrolic-N coordination (SNC) is synthesized via the process of hydrothermal and nitridation. In SNC, pentagon-S and pyrrolic-N originating from thiourea precursor are covalently grafted onto the basal plane of the graphene framework, building unsymmetrical dumbbell-like S─C─N motifs, which effectively modulates atomic and electronic structures of graphene. The SNC catalyst delivers ultrahigh H2O2 productivity of 8.1, 7.3, and 3.9 mol gcatalyst -1 h-1 in alkaline, neutral, and acidic electrolytes, respectively, together with long-term operational stability in pH-universal electrolytes, outperforming most reported carbon catalysts. Theoretical calculations further unveil that defective S─C─N motifs efficiently optimize the binding strength to OOH* intermediate and substantially diminish the kinetic barrier for reducing O2 to H2O2, thereby promoting the intrinsic activity of 2e-ORR.

3.
Small ; 19(19): e2207082, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36755088

RESUMO

Seawater is the most abundant natural water resource in the world, which is an inexhaustible and low-cost feedstock for hydrogen production by alkaline water electrolysis. It is appearling to develop robust and stable electrocatalysts for alkaline seawater electrolysis. However, the development of seawater electrolysis is seriously impeded by anodic chloride corrosion and chlorine evolution reaction, and few non-noble electrocatalysts show prominent catalytic performance and excellent durability. Here, a heterogeneous electrocatalyst constructed by in situ growing highly dispersed iron-rich bimetallic phosphide nanoparticles on metallic Ni3 N (Fe2-2 x Co2 x P/Ni3 N), which exhibits outstanding bifunctional catalytic activities for alkaline seawater splitting, is reported. The optimal (Fe0.74 Co0.26 )2 P/Ni3 N and Fe2 P/Ni3 N electrocatalysts demand only 113 and 212 mV to afford 100 mA cm-2 for hydrogen and oxygen evolution reactions (HER and OER) in 1 m KOH, respectively, thus substantially expediting overall water/seawater electrolysis at 100 mA cm-2 with 1.592/1.645 V. Particularly, Fe2 P/Ni3 N displays an unprecedented overpotential of 302 mV at 500 mA cm-2 , which represents the best alkaline seawater oxygen evolution activity among the ever-reported non-noble electrocatalysts; and thus substantially expedites overall water/seawater splitting at 500 mA cm-2 with 1.701/1.768 V, surpassing most of the reported non-noble lectrocatalysts. This work provides a new approach for developing high-performance electrocatalysts for seawater splitting.

4.
Angew Chem Int Ed Engl ; 62(46): e202306896, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37747767

RESUMO

Developing efficient and robust hydrogen evolution reaction (HER) catalysts for scalable and sustainable hydrogen production through electrochemical water splitting is strategic and challenging. Herein, heterogeneous Mo8 O26 -NbNx Oy supported on N-doped graphene (defined as Mo8 O26 -NbNx Oy /NG) is synthesized by controllable hydrothermal reaction and nitridation process. The O-exposed Mo8 O26 clusters covalently confined on NbNx Oy nanodomains provide a distinctive interface configuration and appropriate electronic structure, where fully exposed multiple active sites give excellent HER performance beyond commercial Pt/C catalyst in pH-universal electrolytes. Theoretical studies reveal that the Mo8 O26 -NbNx Oy interface with electronic reconstruction affords near-optimal hydrogen adsorption energy and enhanced initial H2 O adsorption. Furthermore, the terminal O atoms in Mo8 O26 clusters cooperate with Nb atoms to promote the initial H2 O adsorption, and subsequently reduce the H2 O dissociation energy, accelerating the entire HER kinetics.

5.
Small ; 18(1): e2104624, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34761500

RESUMO

Alkaline water electrolysis is an advanced technology for scalable H2 production using surplus electricity from intermittent energy sources, but it remains challenging for non-noble electrocatalysts to split water into hydrogen and oxygen efficiently, especially for tungsten disulfide (WS2 )-based catalysts. Density functional theory calculations in combination with experimental study are used to establish a multi-site engineering strategy for developing robust WS2 -based hybrid electrocatalyst on mesoporous bimetallic nitride (Ni3 FeN) nanoarrays for bifunctional water splitting. This ingenious design endows the catalyst with numerous edge sites chemically bonded with the conductive scaffold, which are favorable for water dissociation and hydrogen adsorption. Benefiting from the synergistic advantages, the N-WS2 /Ni3 FeN hybrid exhibits exceptional bifunctional properties for hydrogen and oxygen evolution reactions (HER and OER) in base with excellent large-current durability, requiring 84 mV to afford 10 mA cm-2 for HER, and 240 mV at 100 mA cm-2 for OER, respectively. Assembling the catalytic materials as both the anode and cathode to construct an electrolyzer, it is actualized very good activities for overall water splitting with only 1.5 V to deliver 10 mA cm-2 , outperforming the IrO2 (+) //Pt(-) coupled electrodes and many non-noble bifunctional electrocatalysts thus far. This work provides a promising avenue for designing WS2 -based heterogeneous electrocatalysts for water electrolysis.

6.
Small ; 18(4): e2105642, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34825490

RESUMO

The catalytic hydrogen-evolving activities of transition-metal phosphides are greatly related to the phosphorus content, but the physical origin of performance enhancement remains ambiguous, and tuning the catalytic activity of nickel phosphides (NiP2 /Ni5 P4 ) remains challenging due to unfavorable H* adsorption. Here, a strategy is introduced to integrate P-rich NiP2 and P-poor Ni5 P4 into in-plane heterostructures by anion substitution, in which P atoms at the in-plane interfaces perform as active sites to adsorb H* and thus facilitate the hydrogen evolution reaction (HER) process via modulating the electronic structure between NiP2 and Ni5 P4 . Consequently, the NiP2 /Ni5 P4 hybrid exhibits an outstanding hydrogen-evolving activity, requiring only 30 and 76 mV to afford 10 and 100 mA cm-2 in acid, respectively. It surpasses most of the earth-abundant electrocatalysts thus far, and is comparable to Pt catalysts (30/72 mV at 10/100 mA cm-2 ). Particularly, it can run smoothly at large current density and only requires 247 mV to reach 2000 mA cm-2 . Detailed theoretical calculations reveal that its exceptional activity stems from the moderate overlap of density states between P 2p and H 1s orbitals, thus optimizing the H*-adsorption strength. This work highlights a new avenue toward the fabrication of robust non-noble electrocatalysts by constructing in-plane heterojunctions.

7.
Small ; 18(40): e2203171, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36047970

RESUMO

Earth-abundant layered tungsten disulfide (WS2 ) is a well-known electrocatalyst for acidic hydrogen evolution, but it becomes rather sluggish for alkaline hydrogen or oxygen evolution due to the low-density edge sites, poor conductivity, and unfavorable water dissociation behavior. Here, an interfacial engineering strategy to construct an efficient bifunctional electrocatalyst by in situ growing N-doped WS2 nanoparticles on highly conductive cobalt nitride (N-WS2 /Co3 N) for concurrent hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) is demonstrated. Benefiting from the good conductivity of Co3 N, rich well-oriented edge sites and water-dissociation sites at the nanoscale interfaces between N-WS2 and Co3 N, the resultant N-WS2 /Co3 N exhibits remarkable HER activity in 1 m potasium hydroxide (KOH) requiring a small overpotential of 67 mV at 10 mA cm-2 with outstanding long-term durability at 500 mA cm-2 , representing the best alkaline hydrogen-evolving activity among reported WS2 catalysts. In particular, this hybrid catalyst also shows exceptional catalytic activities toward theurea oxidation reaction featured by very low potentials of 1.378 and 1.41 V to deliver 100 and 500 mA cm-2 along with superb large-current stability in 1 m KOH + 0.5 m urea. Moreover, the assembled two-electrode cell delivers the industrially practical current density of 500 mA cm-2 at a low cell voltage of 1.72 V with excellent durability in alkaline urea-containing solutions, outperforming most MoS2 -like bifunctional electrocatalysts for overall water splitting reported hitherto. This work provides a promising avenue for the development of high-performance WS2 -based electrocatalysts for alkaline water splitting.

8.
Small ; 16(13): e1906629, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32133786

RESUMO

Developing efficient non-noble and earth-abundant hydrogen-evolving electrocatalysts is highly desirable for improving the energy efficiency of water splitting in base. Molybdenum disulfide (MoS2 ) is a promising candidate, but its catalytic activity is kinetically retarded in alkaline media due to the unfavorable water adsorption and dissociation feature. A heterogeneous electrocatalyst is reported that is constructed by selenium-doped MoS2 (Se-MoS2 ) particles on 3D interwoven cobalt diselenide (CoSe2 ) nanowire arrays that drives the hydrogen evolution reaction (HER) with fast reaction kinetics in base. The resultant Se-MoS2 /CoSe2 hybrid exhibits an outstanding catalytic HER performance with extremely low overpotentials of 30 and 93 mV at 10 and 100 mA cm-2 in base, respectively, which outperforms most of the inexpensive alkaline HER catalysts, and is among the best alkaline catalytic activity reported so far. Moreover, this hybrid catalyst shows exceptional catalytic performance with very low overpotentials of 84 and 95 mV at 10 mA cm-2 in acidic and neutral electrolytes, respectively, implying robust pH universality of this hybrid catalyst. This work may provide new inspirations for the development of high-performance MoS2 -based HER electrocatalysts in unfavorable basic media for promising catalytic applications.

9.
Proc Natl Acad Sci U S A ; 114(22): 5607-5611, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28507120

RESUMO

Commercial hydrogen production by electrocatalytic water splitting will benefit from the realization of more efficient and less expensive catalysts compared with noble metal catalysts, especially for the oxygen evolution reaction, which requires a current density of 500 mA/cm2 at an overpotential below 300 mV with long-term stability. Here we report a robust oxygen-evolving electrocatalyst consisting of ferrous metaphosphate on self-supported conductive nickel foam that is commercially available in large scale. We find that this catalyst, which may be associated with the in situ generated nickel-iron oxide/hydroxide and iron oxyhydroxide catalysts at the surface, yields current densities of 10 mA/cm2 at an overpotential of 177 mV, 500 mA/cm2 at only 265 mV, and 1,705 mA/cm2 at 300 mV, with high durability in alkaline electrolyte of 1 M KOH even after 10,000 cycles, representing activity enhancement by a factor of 49 in boosting water oxidation at 300 mV relative to the state-of-the-art IrO2 catalyst.

10.
Small ; 15(6): e1804272, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30637939

RESUMO

Facile design of low-cost and high-efficiency catalysts with earth-abundant and cheap materials is desirable to replace platinum (Pt) for the hydrogen evolution reaction (HER) in water splitting, but the development of such HER catalysts with Pt-like activity using simple strategies remains challenging. A mesoporous hybrid catalyst of nickel phosphides nanoparticles and cobalt phosphosulfide/phosphide (CoS|Ni|P) nanosheet arrays for HER is reported here, which is developed by a facile three-step approach consisting of electrodeposition, thermal sulfurization, and phosphorization. This hybrid catalyst is highly robust and stable in acid for HER, and is distinguished by very low overpotentials of 41, 88, and 150 mV to achieve 10, 100, and 1000 mA cm-2 , respectively, as well as a small Tafel slope (45.2 mV dec-1 ), and a large exchange current density (964 µA cm-2 ). It is among the most efficient earth-abundant catalysts reported thus far for HER. More importantly, this electrocatalyst has electrochemical durability over 20 h under a wide range of current densities (up to 1 A cm-2 ) in acidic conditions, as well as very high turnover frequencies of 0.40 and 1.26 H2 s-1 at overpotentials of 75 and 100 mV, respectively, showing that it has great potential for practical applications in large-scale water electrolysis.

11.
Nano Lett ; 16(12): 7604-7609, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27805408

RESUMO

The large consumption of natural fossil fuels and accompanying environmental problems are driving the exploration of cost-effective and robust catalysts for hydrogen evolution reaction (HER) in water splitting. Tungsten dichalcogenides (WS2, WSe2, etc.) are promising candidates for such purpose, but their HER performances are inherently limited by the sparse catalytic edge sites and poor electrical conductivity. Here we demonstrate a highly active and stable HER catalyst by integrating ternary tungsten sulfoselenide WS2(1-x)Se2x particles with a 3D porous metallic NiSe2 foam, in which good electrical conductivity, good contact, large surface area, and high-density active edge sites are simultaneously obtained, thus contributing to outstanding catalytic performance: large cathode current density (-10 mA/cm2 at -88 mV), low Tafel slope (46.7 mV/dec), large exchange current density (214.7 µA/cm2), and good stability, which is better than most reports on WS2 and NiSe2 catalysts. This work paves an interesting route for boosting HER efficiency of transition metal dichalcogenide catalysts.

12.
Phys Rev Lett ; 115(2): 022001, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-26207462

RESUMO

By using a combined amplitude analysis of the γγ→DD̅ and γγ→J/ψω data, we demonstrate that the X(3915), which is quoted as a J(PC)=0(++) state in the Particle Data Group table, is favored by the data to be a J(PC)=2(++) state appearing in both channels, which means that the X(3915) and the X(3930) can be regarded as the same J(PC)=2(++) state. Meanwhile, the data also prefer a large helicity-0 contribution of this tensor resonance to the amplitudes instead of the helicity-2 dominance assumed by BABAR, which may indicate a sizable portion of non-qq̅ components in this state. Identifying the X(3915) with the X(3930) and abandoning the helicity-2 dominance for this tensor state are helpful for the further understandings of the properties of this state and also of the mysterious "XYZ" charmoniumlike resonances.

13.
Angew Chem Int Ed Engl ; 53(6): 1565-9, 2014 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-24453109

RESUMO

Bi- and trilayer graphene have attracted intensive interest due to their rich electronic and optical properties, which are dependent on interlayer rotations. However, the synthesis of high-quality large-size bi- and trilayer graphene single crystals still remains a challenge. Here, the synthesis of 100 µm pyramid-like hexagonal bi- and trilayer graphene single-crystal domains on Cu foils using chemical vapor deposition is reported. The as-produced graphene domains show almost exclusively either 0° or 30° interlayer rotations. Raman spectroscopy, transmission electron microscopy, and Fourier-transformed infrared spectroscopy were used to demonstrate that bilayer graphene domains with 0° interlayer stacking angles were Bernal stacked. Based on first-principle calculations, it is proposed that rotations originate from the graphene nucleation at the Cu step, which explains the origin of the interlayer rotations and agrees well with the experimental observations.

14.
Adv Mater ; 36(5): e2305685, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37747155

RESUMO

The key dilemma for green hydrogen production via electrocatalytic water splitting is the high overpotential required for anodic oxygen evolution reaction (OER). Co/Fe-based materials show superior catalytic OER activity to noble metal-based catalysts, but still lag far behind the state-of-the-art Ni/Fe-based catalysts probably due to undesirable side segregation of FeOOH with poor conductivity and unsatisfied structural durability under large current density. Here, a robust and durable OER catalyst affording current densities of 500 and 1000 mA cm-2 at extremely low overpotentials of 290 and 304 mV in base is reported. This catalyst evolves from amorphous bimetallic FeOOH/Co(OH)2 heterostructure microsheet arrays fabricated by a facile mechanical stirring strategy. Especially, in situ X-ray photoelectron spectroscopy (XPS) and Raman analysis decipher the rapid reconstruction of FeOOH/Co(OH)2 into dynamically stable Co1-x Fex OOH active phase through in situ iron incorporation into CoOOH, which perform as the real active sites accelerating the rate-determining step supported by density functional theory calculations. By coupling with MoNi4 /MoO2 cathode, the self-assembled alkaline electrolyzer can deliver 500 mA cm-2 at a low cell voltage of 1.613 V, better than commercial IrO2 (+) ||Pt/C(-) and most of reported transition metal-based electrolyzers. This work provides a feasible strategy for the exploration and design of industrial water-splitting catalysts for large-scale green hydrogen production.

15.
Patient Educ Couns ; 127: 108365, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38991460

RESUMO

OBJECTIVE: While there are various health literacy scales that exist, none of health literacy scale suitable for pregnant women with gestational diabetes mellitus (GDM). To address this gap, this study aimed to develop GDM health literacy scale and evaluate its psychometric properties. METHODS: Based on the Delphi expert consultation, we developed the initial GDM health literacy scale. Item analysis was taken using a sample (n = 299) recruited in China to form formal scale. Additional participants (n = 395) completed survey to assess the internal consistency reliability, test-retest reliability, content validity, construct validity and criterion correlation validity of scale. RESULTS: The scale performed well in terms of internal consistency reliability, content validity, construct validity and criterion correlation validity. Test-retest reliability indicated that the instrument was effective at measuring health literacy of GDM over time. CONCLUSION: The scale is a reliable and valid measure of six domains of health literacy for GDM. PRACTICE IMPLICATIONS: The scale can be used to effectively evaluate the level of health literacy of pregnant women with GDM. The information can provide targeted health support for pregnant women with GDM to improve their health literacy and self-management ability.

16.
Adv Mater ; : e2405852, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39021291

RESUMO

The utilization of seawater for hydrogen production via water splitting is increasingly recognized as a promising avenue for the future. The key dilemma for seawater electrolysis is the incompatibility of superior hydrogen- and oxygen-evolving activities at ampere-scale current densities for both cathodic and anodic catalysts, thus leading to large electric power consumption of overall seawater splitting. Here, in situ construction of Fe4N/Co3N/MoO2 heterostructure arrays anchoring on metallic nickel nitride surface with multilevel collaborative catalytic interfaces and abundant multifunctional metal sites is reported, which serves as a robust bifunctional catalyst for alkaline freshwater/seawater splitting at ampere-level current density. Operando Raman and X-ray photoelectron spectroscopic studies combined with density functional theory calculations corroborate that Mo and Co/Fe sites situated on the Fe4N/Co3N/MoO2 multilevel interfaces optimize the reaction pathway and coordination environment to enhance water adsorption/dissociation, hydrogen adsorption, and oxygen-containing intermediate adsorption, thus cooperatively expediting hydrogen/oxygen evolution reactions in base. Inspiringly, this electrocatalyst can substantially ameliorate overall freshwater/seawater splitting at 1000 mA cm-2 with low cell voltages of 1.65/1.69 V, along with superb long-term stability at 500-1500 mA cm-2 for over 200 h, outperforming nearly all the ever-reported non-noble electrocatalysts for freshwater/seawater electrolysis. This work offers a viable approach to design high-performance bifunctional catalysts for seawater splitting.

17.
ACS Nano ; 18(17): 11474-11486, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38632861

RESUMO

Cobalt-nitrogen-carbon (Co-N-C) catalysts with a CoN4 structure exhibit great potential for oxygen reduction reaction (ORR), but the imperfect adsorption energy toward oxygen species greatly limits their reduction efficiency and practical application potential. Here, F-coordinated Co-N-C catalysts with square-pyramidal CoN4-F1 configuration are successfully synthesized using F atoms to regulate the axial coordination of Co centers via hydrothermal and chemical vapor deposition methods. During the synthesis process, the geometry structure of the Co atom converts from six-coordinated Co-F6 to square-pyramidal CoN4-F1 in the coordinatively unsaturated state, which provides an open binding site for the O2. The introduction of axial F atoms into the CoN4 plane alters the local atomic environment around Co, significantly improving the ORR activity and Zn-air batteries performance. In situ spectroscopy proves that CoN4-F1 sites strongly combine with the OOH* intermediate and facilitate the splitting of O-O bond, making OOH* readily decompose into O* and OH* via a dissociative pathway. Theoretical calculations confirm that the axial F atom effectively reduces the electronic density of the Co centers and facilitates the desorption of the OH* intermediate, efficiently accelerating the overall ORR kinetics. This work advances a feasible synthesis mechanism of axial ligands and provides a route to construct efficient high-coordination catalysts.

18.
J Am Chem Soc ; 135(29): 10755-62, 2013 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-23815279

RESUMO

Precise spatial control of materials is the key capability of engineering their optical, electronic, and mechanical properties. However, growth of graphene on Cu was revealed to be seed-induced two-dimensional (2D) growth, limiting the synthesis of complex graphene spatial structures. In this research, we report the growth of onion ring like three-dimensional (3D) graphene structures, which are comprised of concentric one-dimensional hexagonal graphene ribbon rings grown under 2D single-crystal monolayer graphene domains. The ring formation arises from the hydrogenation-induced edge nucleation and 3D growth of a new graphene layer on the edge and under the previous one, as supported by first principles calculations. This work reveals a new graphene-nucleation mechanism and could also offer impetus for the design of new 3D spatial structures of graphene or other 2D layered materials. Additionally, in this research, two special features of this new 3D graphene structure were demonstrated, including nanoribbon fabrication and potential use in lithium storage upon scaling.

19.
Small ; 9(14): 2405-9, 2013 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-23650121

RESUMO

Intramolecular junctions can be formed in single-walled carbon nanotubes (SWNTs) by introducing a pentagon and/or heptagon into the hexagonal carbon lattice. The realization of these carbon-based molecular electronics is still quite challenging. Here, it is reported that nickel or cobalt catalyzed etching can be applied to partially unzip an SWNT into an intermolecular junction of SWNT/graphene nanoribbon, directly confirmed by atomic force microscopy and Raman spectroscopy.

20.
Nanotechnology ; 24(15): 155203, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23519272

RESUMO

Metal structures with high optical transparency and conductivity are of great importance for practical applications in optoelectronic devices. Here we investigate the transparency response of a continuous metal film sandwiched by double plasmonic nanoparticle arrays. The upper nanoparticle array shows efficient light trapping of the incident field, acting as a light input coupler, and the lower nanoparticle array shows a light release gate opening at the other side, acting as the light output coupler. The strong near-field light-matter interactions of the nano-scale separated plasmonic nanoparticles, the excitation of surface plasmon waves of the metal film, and their cooperative coupling effects result in broadband scattering cancellation and near-unity transparency (up to 96%) in the optical regime. The transparency response in such a structure can be efficiently modified by varying the gap distance of adjacent nanoparticles, dielectric environments, and the distance between the plasmonic array and the metal film. This motif may provide a new alternative approach to obtain transparent and highly conducting metal structures with potential applications in transparent conductors, plasmonic filters, and highly integrated light input and output components.

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