Photoluminescence(PL) from bulk noble metals arises from the interband transition of bound electrons. Plasmonic nanostructures can greatly enhance the quantum yield of noble metals through the localized surface plas...Photoluminescence(PL) from bulk noble metals arises from the interband transition of bound electrons. Plasmonic nanostructures can greatly enhance the quantum yield of noble metals through the localized surface plasmon. In this work,we briefly review recent progress on the phenomenon, mechanism, and application of one-photon PL from plasmonic nanostructures. Particularly, our recent efforts in the study of the PL peak position, partial depolarization, and mode selection from plasmonic nanostructures can bring about a relatively complete and deep understanding of the physical mechanism of one-photon PL from plasmonic nanostructures, paving the way for future applications in plasmonic imaging,plasmonic nanolasing, and surface enhanced fluorescence spectra.展开更多
Nanozymes,as a novel form of enzyme mimics,have garnered considerable interest.Despite overcoming the main disadvantages of their natural analogs,they still face challenges such as restricted mimic types and low subst...Nanozymes,as a novel form of enzyme mimics,have garnered considerable interest.Despite overcoming the main disadvantages of their natural analogs,they still face challenges such as restricted mimic types and low substrate specificity.Herein,we introduce a reactive ligand modification strategy to diversify enzyme mimic types.Specifically,we have utilized helical plasmonic nanorods(HPNRs)modified with para-nitrothiophenol(4-NTP)to create an oxygen-sensitive nitroreductase(NTR)with light-controllability.HPNRs act as a light-adjustable source of nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate(NAD(P)H),providing photon-generated energetic electrons to adsorbed 4-NTP molecules.In the presence of O_(2),the activated 4-NTP transfers the captured electron to the adsorbed O_(2),mimicking the electron transfer process in its natural counterpart.This enhanced O_(2)activation notably boosts the oxidative coupling of para-aminothiophenol(4-ATP).Density functional theory(DFT)calculations reveal that hot electrons injected into the lowest unoccupied molecular orbital(LUMO)energy level of 4-NTP can be transferred to that of molecular oxygen.In conclusion,our findings underline the potential of the reactive ligand modification strategy in developing new types of enzyme reactions,which opens up promising avenues for the enhancement and diversification of nanozyme functionalities.展开更多
Here,we use two important biomaterials,protein and DNA,to construct self-assembled linear nanostructures through Watson-Crick base-paring of DNAs.We apply a simple magnetic separation method to purify traptavidin-DNA ...Here,we use two important biomaterials,protein and DNA,to construct self-assembled linear nanostructures through Watson-Crick base-paring of DNAs.We apply a simple magnetic separation method to purify traptavidin-DNA co njugates,and demonstrate synthesis of linear arrays of traptavidinDNA conjugates via the step-growth polymerization approach with pre-determined DNA sequences.Using the traptavidin-DNA array as a template,we assemble gold nanoparticles to form linear plasmonic nanostructures in a programmable manner.The traptavidin-DNA conjugates thus provide a convenient platform for one-dimensional assembly of biotinylated nanomaterials for many biomedical applications from drug delivery to bio-sensing.展开更多
Enriching the library of chiral plasmonic structures is of significant importance in advancing their applicability across diverse domains such as biosensing,nanophotonics,and catalysis.Here,employing triangle nanoplat...Enriching the library of chiral plasmonic structures is of significant importance in advancing their applicability across diverse domains such as biosensing,nanophotonics,and catalysis.Here,employing triangle nanoplates as growth seeds,we synthesized a novel class of chiral-shaped plasmonic nanostructures through a wet chemical strategy with dipeptide as chiral inducers,including chiral tri-blade boomerangs,concave rhombic dodecahedrons,and nanoflowers.The structural diversity in chiral plasmonic nanostructures was elucidated through their continuous morphological evolution from two-dimensional to threedimensional architectures.The fine-tuning of chiroptical properties was achieved by precisely manipulating crucial synthetic parameters such as the amount of chiral molecules,seeds,and gold precursor that significantly influenced chiral structure formation.The findings provide a promising avenue for enriching chiral materials with highly sophisticated structures,facilitating a fundamental understanding of the relationship between structural nuances and chiroptical properties.展开更多
Plasmonic catalysis is emerging as a dynamic field in heterogeneous catalysis and holds great promise for the efficient utilization of solar energy.Central to the development of plasmonic catalysis is the design of ef...Plasmonic catalysis is emerging as a dynamic field in heterogeneous catalysis and holds great promise for the efficient utilization of solar energy.Central to the development of plasmonic catalysis is the design of efficient plasmonic nanocatalysts.In this report,plasmonic gap nanostructures(PGNs)on the basis of Au@poly(o-phenylenediamine)(POPD)@Pd sandwich nanostructures are synthesized as plasmonic nanocatalysts by an in-situ reduction synthetic strategy,which allows for the precise engineering of the POPD gap size between plasmonic Au and catalytic Pd components.The introduction of conducting POPD nanogap in PGNs not only effectively enhances their light harvesting capability,but also provides an effective charge transfer channel for harnessing the photogenerated hot charge carriers.In this respect,distinct gap-dependent performances in plasmon-enhanced electrocatalysis of ethanol oxidation reactions(EOR)are demonstrated with the PGN nanocatalysts and over 2.5 folds of enhancement can be achieved.A volcano plot is derived to describe the relationship between the catalytic activities and gap size of the PGN nanocatalysts,which is well explained by the interplay of their light harvesting and charge transport capabilities.These results highlight the importance of gap engineering in PGNs for plasmonic catalysis and offer the promise of developing efficient plasmonic nanocatalysts for other heterogeneous catalytic reactions.展开更多
We report direct nanoscale imaging of ultrafast plasmon in a gold dolmen nanostructure excited with the 7is laser pulses by combining the interferometric time-resolved technology with the three-photon photoemission el...We report direct nanoscale imaging of ultrafast plasmon in a gold dolmen nanostructure excited with the 7is laser pulses by combining the interferometric time-resolved technology with the three-photon photoemission electron microscopy (PEEM). The interferometric time-resolved traces show that the plasmon mode beating pattern appears at the ends of the dimer slabs in the dolmen nanostructure as a result of coherent superposition of multiple localized surface plasmon modes induced by broad bandwidth of the ultrafast laser pulses. The PEEM measurement further discloses that in-phase of the oscillation field of two neighbor defects are surprisingly observed, which is attributed to the plasmon coupling between them. Furthermore, the control of the temporal delay between the pump and probe laser pluses could be utilized for manipulation of the near-field distribution. These findings deepen our understanding of ultrafast plasmon dynamics in a complex nanosystem.展开更多
We report the direct imaging of plasmon on the tips pulses and probing of ultrafast plasmon dynamics by of nano-prisms in a bowtie structure excited by 7 fs laser combining the pump-probe technology with three-photon ...We report the direct imaging of plasmon on the tips pulses and probing of ultrafast plasmon dynamics by of nano-prisms in a bowtie structure excited by 7 fs laser combining the pump-probe technology with three-photon photoemission electron microscopy. Different photoemission patterns induced by the plasmon effect are observed when the bowties are excited by s- and p-polarized femtosecond laser pulses. A series of images of the evolution of local surface plasmon modes on different tips of the bowtie are obtained by the time-resolved three-photon photoemission electron microscopy, and the result discloses that plasmon excitation is dominated by the interfer- ence of the pump and probe pulses within the first 13 fs of the delay time, and thereafter the individual plasmon starts to oscillate on its own characteristic resonant frequencies.展开更多
The application of three-dimensional(3D)plasmonic nanostructures as metamaterials(MMs),nano-antennas,and other devices faces challenges in producing metallic nanostructures with easily definable orientations,sophistic...The application of three-dimensional(3D)plasmonic nanostructures as metamaterials(MMs),nano-antennas,and other devices faces challenges in producing metallic nanostructures with easily definable orientations,sophisticated shapes,and smooth surfaces that are operational in the optical regime and beyond.Here,we demonstrate that complex 3D nanostructures can be readily achieved with focused-ion-beam irradiation-induced folding and examine the optical characteristics of plasmonic“nanograter”structures that are composed of free-standing Au films.These 3D nanostructures exhibit interesting 3D hybridization in current flows and exhibit unusual and well-scalable Fano resonances at wavelengths ranging from 1.6 to 6.4 mm.Upon the introduction of liquids of various refractive indices to the structures,a strong dependence of the Fano resonance is observed,with spectral sensitivities of 1400 nm and 2040 nm per refractive index unit under figures of merit of 35.0 and 12.5,respectively,for low-order and high-order resonance in the near-infrared region.This work indicates the exciting,increasing relevance of similarly constructed 3D free-standing nanostructures in the research and development of photonics and MMs.展开更多
Life has evolved numerous elegant molecular machines that recognize biological signals and affect mechanical changes precisely to achieve specific and versatile biofunctions.Inspired by nature,synthetic molecular mach...Life has evolved numerous elegant molecular machines that recognize biological signals and affect mechanical changes precisely to achieve specific and versatile biofunctions.Inspired by nature,synthetic molecular machines could be designed rationally to realize nanomechanical operations and autonomous computing.We constructed logic-gated plasmonic nanodevices through coassembly of two gold nanorods(AuNRs)and computing elements on a tweezer-shaped DNA origami template.After recognition of various molecular inputs,such as DNA strands,glutathione,or adenosine,the geometry and plasmonic circular dichroism(CD)signals of the AuNR–origami nanodevices produced corresponding changes.Then we designed and characterized a set of modular Boolean logic-gated nanodevices(YES,NOT,AND,OR)and proceeded to construct a complicated 3-input circuit capable of performing Boolean OR-NOT-AND operations.Our plasmonic logic devices transduced external inputs into conformational changes and near-infrared(NIR)chiral outputs.This DNA-based self-assembly strategy holds great potential for applications in programmable optical modulators,molecular information processing,and bioanalysis.展开更多
Formation of plasmonic structure in closely packed assemblies of metallic nanoparticles(NPs)is essential for various applications in sensing,renewable energy,authentication,catalysis,and metamaterials.Herein,a surface...Formation of plasmonic structure in closely packed assemblies of metallic nanoparticles(NPs)is essential for various applications in sensing,renewable energy,authentication,catalysis,and metamaterials.Herein,a surface-enhanced Raman scattering(SERS)substrate is fabricated for trace detection with ultrahigh sensitivity and stability.The SERS substrate is constructed from a simple yet robust strategy through in situ growth patterned assemblies of Au NPs based on a polymer brush templated synthesis strategy.Benefiting from the dense and uniform distribution of Au NPs,the resulting Au plasmonic nanostructure demonstrates a very strong SERS effect,while the outer polymer brush could restrict the excessive growth of Au NPs and the patterned design could achieve uniform distribution of Au NPs.As results,an ultra-low limit of detection(LOD)of 10^(−15)M,which has never been successfully detected in other work,is determined for 4-acetamidothiophenol(4-AMTP)molecules and the Raman signals in the random region show good signal homogeneity with a low relative standard deviation(RSD)of 7.2%,indicating great sensitivity and reliability as a SERS substrate.The LOD values of such Au plasmonic nanostructures for methylene blue,thiram,and R6G molecules can also reach as low as 10^(−10)M,further indicating that the substrate has a wide range of applicability for SERS detection.With the help of finite difference time domain simulations(FDTD)calculation,the electric field distribution of the Au plasmonic nanostructures is simulated,which quantitatively matches the experimental observations.Moreover,the Au plasmonic nanostructures show good shelf stability for at least 10 months of storage in an ambient environment,indicating potentials for practical applications.展开更多
Structural colors resulting from nanostructured metallic surfaces hold a series of advantages compared to conventional chemical pigments and dyes,such as enhanced durability,tunability,scalability,and low consumption,...Structural colors resulting from nanostructured metallic surfaces hold a series of advantages compared to conventional chemical pigments and dyes,such as enhanced durability,tunability,scalability,and low consumption,making them particularly promising for preparing color-tunable devices.However,once these structures are fabricated,they are almost all passive devices with static nanostructures and fixed optical properties,limiting their potential applications.Here,by using a specially designed array of ordered SiO2 nanoholes as a deposition template in conjunction with the traditional reversible metal electrodeposition device(RMED),we propose a tunable reflective surface where the color of the surface can be changed as a function of the thickness of the deposited Ag nanoparticles(AgNPs).Simplified manufacturability and a large range of color tunability are achieved over previous reports by utilizing the SiO2 nanohole template,which allows the direct deposition of AgNPs while forming an array structure of Ag nanocylinders.Besides,a further thematic analysis of the physical mechanism in the proposed structure is conducted.The results show that the structural colors induced by the longitudinal localized surface plasmon resonance(LSPR)mode can be dynamically tuned from brown to purple via increasing the deposition thickness.Additionally,in combination with SiO2 nanohole templates of varying parameters,a full gamut of colors spanning the entire visible spectrum is achieved,revealing the feasibility of utilizing the properties of the LSPR mode for satisfying various color requirements.We believe that this LSPRbased multicolor RMED design will contribute to the development of full color information displays and light-modulating devices.展开更多
The possibility to achieve unprecedented multiplexing of light-matter interaction in nanoscale is of virtue importance from both fundamental science and practical application points of view. Cylindrical vector beams(C...The possibility to achieve unprecedented multiplexing of light-matter interaction in nanoscale is of virtue importance from both fundamental science and practical application points of view. Cylindrical vector beams(CVBs) manifested as polarization vortices represent a robust and emerging degree of freedom for information multiplexing with increased capacities. Here, we propose and demonstrate massivelyencoded optical data storage(ODS) by harnessing spatially variant electric fields mediated by segmented CVBs. By tight focusing polychromatic segmented CVBs to plasmonic nanoparticle aggregates, recordhigh multiplexing channels of ODS through different combinations of polarization states and wavelengths have been experimentally demonstrated with a low error rate. Our result not only casts new perceptions for tailoring light-matter interactions utilizing structured light but also enables a new prospective for ultra-high capacity optical memory with minimalist system complexity by combining CVB’s compatibility with fiber optics.展开更多
Owing to the unique advantages of surface enhanced Raman scattering(SERS)in high sensitivity,specificity,multiplexing capability and photostability,it has been widely used in many applications,among which SERS biosens...Owing to the unique advantages of surface enhanced Raman scattering(SERS)in high sensitivity,specificity,multiplexing capability and photostability,it has been widely used in many applications,among which SERS biosensing and bioimaging are the focus in recent years.The successful applications of SERS for non-invasive biomarker detection and bioimaging under in vitro,in vivo and ex vivo conditions,offer significant clinical information to improve diagnostic and prognostic outcomes.This review provides recent developments and applications of SERS,in particular SERS nanotags in biosensing and bioimaging,describing case studies in which different types of biomarkers have been investigated,as well as outlining future challenges that need to be addressed before SERS sees both pathological and clinical use.展开更多
Optical absorption in thin-film solar cells can be improved by using surface plasmons for guiding and confining the light on the nanoscale.We report theoretical and simulation studies of a-Si thin-film solar cells wit...Optical absorption in thin-film solar cells can be improved by using surface plasmons for guiding and confining the light on the nanoscale.We report theoretical and simulation studies of a-Si thin-film solar cells with silver nanocylinders on the surface.We found that surface plasmons increased the cells' spectral response over almost the entire studied solar spectrum.In the ultraviolet range and at wavelengths close to the Si band gap we observed a significant enhancement of the absorption for both thin-film and wafer-based structures.We also performed optimization studies of particle size,inter-particle distance,and dielectric environment,for obtaining maximal absorption within the substrate.A blue-shift of the resonance wavelength with increasing inter-particle distance was observed in the visible range.Cell performance improved at optimal spacing,which strongly depended on the nanoparticle size.Increasing the nanocylinder size was accompanied by the widening of the plasmon resonance band and a red-shift of the plasmon resonance peaks.A weak red-shift and plasmon peak enhancement were observed in the reflectance curve with increasing refractive index of the dielectric spacer.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61675096 and 61205042)the Natural Science Foundation of Jiangsu Province in China(Grant No.BK20141393)the Singapore Ministry of Education Academic Research Fund Tier 3(Grant No.MOE2011-T3-1-005)and Tier 2(Grant No.MOE2012-T2-2-124)
文摘Photoluminescence(PL) from bulk noble metals arises from the interband transition of bound electrons. Plasmonic nanostructures can greatly enhance the quantum yield of noble metals through the localized surface plasmon. In this work,we briefly review recent progress on the phenomenon, mechanism, and application of one-photon PL from plasmonic nanostructures. Particularly, our recent efforts in the study of the PL peak position, partial depolarization, and mode selection from plasmonic nanostructures can bring about a relatively complete and deep understanding of the physical mechanism of one-photon PL from plasmonic nanostructures, paving the way for future applications in plasmonic imaging,plasmonic nanolasing, and surface enhanced fluorescence spectra.
基金supported by the National Key Basic Research Program of China(No.2021YFA1202803)the National Natural Science Foundation of China(No.22072032)the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB36000000)。
文摘Nanozymes,as a novel form of enzyme mimics,have garnered considerable interest.Despite overcoming the main disadvantages of their natural analogs,they still face challenges such as restricted mimic types and low substrate specificity.Herein,we introduce a reactive ligand modification strategy to diversify enzyme mimic types.Specifically,we have utilized helical plasmonic nanorods(HPNRs)modified with para-nitrothiophenol(4-NTP)to create an oxygen-sensitive nitroreductase(NTR)with light-controllability.HPNRs act as a light-adjustable source of nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate(NAD(P)H),providing photon-generated energetic electrons to adsorbed 4-NTP molecules.In the presence of O_(2),the activated 4-NTP transfers the captured electron to the adsorbed O_(2),mimicking the electron transfer process in its natural counterpart.This enhanced O_(2)activation notably boosts the oxidative coupling of para-aminothiophenol(4-ATP).Density functional theory(DFT)calculations reveal that hot electrons injected into the lowest unoccupied molecular orbital(LUMO)energy level of 4-NTP can be transferred to that of molecular oxygen.In conclusion,our findings underline the potential of the reactive ligand modification strategy in developing new types of enzyme reactions,which opens up promising avenues for the enhancement and diversification of nanozyme functionalities.
基金supported by the Brain Research Program(No.2016M3C7A1904987)through the National Research Foundation of Korea(NRF)。
文摘Here,we use two important biomaterials,protein and DNA,to construct self-assembled linear nanostructures through Watson-Crick base-paring of DNAs.We apply a simple magnetic separation method to purify traptavidin-DNA co njugates,and demonstrate synthesis of linear arrays of traptavidinDNA conjugates via the step-growth polymerization approach with pre-determined DNA sequences.Using the traptavidin-DNA array as a template,we assemble gold nanoparticles to form linear plasmonic nanostructures in a programmable manner.The traptavidin-DNA conjugates thus provide a convenient platform for one-dimensional assembly of biotinylated nanomaterials for many biomedical applications from drug delivery to bio-sensing.
基金supported by the National Natural Science Foundation of China(Nos.22001201 and 22075224)the Science and Technology Agency of Shaanxi Province(No.2022KWZ-21).
文摘Enriching the library of chiral plasmonic structures is of significant importance in advancing their applicability across diverse domains such as biosensing,nanophotonics,and catalysis.Here,employing triangle nanoplates as growth seeds,we synthesized a novel class of chiral-shaped plasmonic nanostructures through a wet chemical strategy with dipeptide as chiral inducers,including chiral tri-blade boomerangs,concave rhombic dodecahedrons,and nanoflowers.The structural diversity in chiral plasmonic nanostructures was elucidated through their continuous morphological evolution from two-dimensional to threedimensional architectures.The fine-tuning of chiroptical properties was achieved by precisely manipulating crucial synthetic parameters such as the amount of chiral molecules,seeds,and gold precursor that significantly influenced chiral structure formation.The findings provide a promising avenue for enriching chiral materials with highly sophisticated structures,facilitating a fundamental understanding of the relationship between structural nuances and chiroptical properties.
基金his work was supported by the National Natural Science Foundation of China(Nos.21974131,22072144,and 22102171)the Department of Science and Technology of Jilin Province(No.20200201080JC)the Natural Science Foundation of Jilin Province(No.YDZJ202201ZYTS341).
文摘Plasmonic catalysis is emerging as a dynamic field in heterogeneous catalysis and holds great promise for the efficient utilization of solar energy.Central to the development of plasmonic catalysis is the design of efficient plasmonic nanocatalysts.In this report,plasmonic gap nanostructures(PGNs)on the basis of Au@poly(o-phenylenediamine)(POPD)@Pd sandwich nanostructures are synthesized as plasmonic nanocatalysts by an in-situ reduction synthetic strategy,which allows for the precise engineering of the POPD gap size between plasmonic Au and catalytic Pd components.The introduction of conducting POPD nanogap in PGNs not only effectively enhances their light harvesting capability,but also provides an effective charge transfer channel for harnessing the photogenerated hot charge carriers.In this respect,distinct gap-dependent performances in plasmon-enhanced electrocatalysis of ethanol oxidation reactions(EOR)are demonstrated with the PGN nanocatalysts and over 2.5 folds of enhancement can be achieved.A volcano plot is derived to describe the relationship between the catalytic activities and gap size of the PGN nanocatalysts,which is well explained by the interplay of their light harvesting and charge transport capabilities.These results highlight the importance of gap engineering in PGNs for plasmonic catalysis and offer the promise of developing efficient plasmonic nanocatalysts for other heterogeneous catalytic reactions.
基金Supported by the National Basic Research Program of China under Grant No 2013CB922404the National Natural Science Foundation of China under Grant Nos 11474040,11474039,61605017 and 61575030the Project of Changchun Science and Technology Bureau under Grant No 14KP007
文摘We report direct nanoscale imaging of ultrafast plasmon in a gold dolmen nanostructure excited with the 7is laser pulses by combining the interferometric time-resolved technology with the three-photon photoemission electron microscopy (PEEM). The interferometric time-resolved traces show that the plasmon mode beating pattern appears at the ends of the dimer slabs in the dolmen nanostructure as a result of coherent superposition of multiple localized surface plasmon modes induced by broad bandwidth of the ultrafast laser pulses. The PEEM measurement further discloses that in-phase of the oscillation field of two neighbor defects are surprisingly observed, which is attributed to the plasmon coupling between them. Furthermore, the control of the temporal delay between the pump and probe laser pluses could be utilized for manipulation of the near-field distribution. These findings deepen our understanding of ultrafast plasmon dynamics in a complex nanosystem.
基金Supported by the National Basic Research Program of China under Grant No 2013CB922404the National Natural Science Foundation of China under Grant Nos 11474040 11274053,11474039 and 61178022the Project under Grant No 14KP007
文摘We report the direct imaging of plasmon on the tips pulses and probing of ultrafast plasmon dynamics by of nano-prisms in a bowtie structure excited by 7 fs laser combining the pump-probe technology with three-photon photoemission electron microscopy. Different photoemission patterns induced by the plasmon effect are observed when the bowties are excited by s- and p-polarized femtosecond laser pulses. A series of images of the evolution of local surface plasmon modes on different tips of the bowtie are obtained by the time-resolved three-photon photoemission electron microscopy, and the result discloses that plasmon excitation is dominated by the interfer- ence of the pump and probe pulses within the first 13 fs of the delay time, and thereafter the individual plasmon starts to oscillate on its own characteristic resonant frequencies.
基金This work was supported by the National Natural Science Foundation of China under grant nos.91123004,61390503,61475186 and 91023041,and XDB07020200by the Technical Talent Program of the Chinese Academy of Sciences.
文摘The application of three-dimensional(3D)plasmonic nanostructures as metamaterials(MMs),nano-antennas,and other devices faces challenges in producing metallic nanostructures with easily definable orientations,sophisticated shapes,and smooth surfaces that are operational in the optical regime and beyond.Here,we demonstrate that complex 3D nanostructures can be readily achieved with focused-ion-beam irradiation-induced folding and examine the optical characteristics of plasmonic“nanograter”structures that are composed of free-standing Au films.These 3D nanostructures exhibit interesting 3D hybridization in current flows and exhibit unusual and well-scalable Fano resonances at wavelengths ranging from 1.6 to 6.4 mm.Upon the introduction of liquids of various refractive indices to the structures,a strong dependence of the Fano resonance is observed,with spectral sensitivities of 1400 nm and 2040 nm per refractive index unit under figures of merit of 35.0 and 12.5,respectively,for low-order and high-order resonance in the near-infrared region.This work indicates the exciting,increasing relevance of similarly constructed 3D free-standing nanostructures in the research and development of photonics and MMs.
基金the National Natural Science Foundation of China(31700871,21773044,51761145044,and 21721002)the National Basic Research Program of China(2016YFA0201601 and 2018YFA0208900)+4 种基金Beijing Municipal Science&Technology Commission(Z191100004819008)Key Research Program of Frontier Sciences,CAS,grant QYZDBSSW-SLH029the Strategic Priority Research Program of Chinese Academy of Sciences(XDB36000000)CAS Interdisciplinary Innovation TeamK.C.Wong Education Foundation(GJTD-2018-03).
文摘Life has evolved numerous elegant molecular machines that recognize biological signals and affect mechanical changes precisely to achieve specific and versatile biofunctions.Inspired by nature,synthetic molecular machines could be designed rationally to realize nanomechanical operations and autonomous computing.We constructed logic-gated plasmonic nanodevices through coassembly of two gold nanorods(AuNRs)and computing elements on a tweezer-shaped DNA origami template.After recognition of various molecular inputs,such as DNA strands,glutathione,or adenosine,the geometry and plasmonic circular dichroism(CD)signals of the AuNR–origami nanodevices produced corresponding changes.Then we designed and characterized a set of modular Boolean logic-gated nanodevices(YES,NOT,AND,OR)and proceeded to construct a complicated 3-input circuit capable of performing Boolean OR-NOT-AND operations.Our plasmonic logic devices transduced external inputs into conformational changes and near-infrared(NIR)chiral outputs.This DNA-based self-assembly strategy holds great potential for applications in programmable optical modulators,molecular information processing,and bioanalysis.
基金supported by the National Natural Science Foundation of China(Nos.21905097,21805091,21774038,and 91856128)the China Postdoctoral Science Foundation(No.L1190440)+2 种基金Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices(No.2019B121203003)the Pearl River Talents Scheme(No.2016ZT06C322)State Key Laboratory of Bio-Fibers and Eco-Textiles(Qingdao University,No.K2019-02).
文摘Formation of plasmonic structure in closely packed assemblies of metallic nanoparticles(NPs)is essential for various applications in sensing,renewable energy,authentication,catalysis,and metamaterials.Herein,a surface-enhanced Raman scattering(SERS)substrate is fabricated for trace detection with ultrahigh sensitivity and stability.The SERS substrate is constructed from a simple yet robust strategy through in situ growth patterned assemblies of Au NPs based on a polymer brush templated synthesis strategy.Benefiting from the dense and uniform distribution of Au NPs,the resulting Au plasmonic nanostructure demonstrates a very strong SERS effect,while the outer polymer brush could restrict the excessive growth of Au NPs and the patterned design could achieve uniform distribution of Au NPs.As results,an ultra-low limit of detection(LOD)of 10^(−15)M,which has never been successfully detected in other work,is determined for 4-acetamidothiophenol(4-AMTP)molecules and the Raman signals in the random region show good signal homogeneity with a low relative standard deviation(RSD)of 7.2%,indicating great sensitivity and reliability as a SERS substrate.The LOD values of such Au plasmonic nanostructures for methylene blue,thiram,and R6G molecules can also reach as low as 10^(−10)M,further indicating that the substrate has a wide range of applicability for SERS detection.With the help of finite difference time domain simulations(FDTD)calculation,the electric field distribution of the Au plasmonic nanostructures is simulated,which quantitatively matches the experimental observations.Moreover,the Au plasmonic nanostructures show good shelf stability for at least 10 months of storage in an ambient environment,indicating potentials for practical applications.
文摘Structural colors resulting from nanostructured metallic surfaces hold a series of advantages compared to conventional chemical pigments and dyes,such as enhanced durability,tunability,scalability,and low consumption,making them particularly promising for preparing color-tunable devices.However,once these structures are fabricated,they are almost all passive devices with static nanostructures and fixed optical properties,limiting their potential applications.Here,by using a specially designed array of ordered SiO2 nanoholes as a deposition template in conjunction with the traditional reversible metal electrodeposition device(RMED),we propose a tunable reflective surface where the color of the surface can be changed as a function of the thickness of the deposited Ag nanoparticles(AgNPs).Simplified manufacturability and a large range of color tunability are achieved over previous reports by utilizing the SiO2 nanohole template,which allows the direct deposition of AgNPs while forming an array structure of Ag nanocylinders.Besides,a further thematic analysis of the physical mechanism in the proposed structure is conducted.The results show that the structural colors induced by the longitudinal localized surface plasmon resonance(LSPR)mode can be dynamically tuned from brown to purple via increasing the deposition thickness.Additionally,in combination with SiO2 nanohole templates of varying parameters,a full gamut of colors spanning the entire visible spectrum is achieved,revealing the feasibility of utilizing the properties of the LSPR mode for satisfying various color requirements.We believe that this LSPRbased multicolor RMED design will contribute to the development of full color information displays and light-modulating devices.
基金the financial support from the National Key R&D Program of China (2018YFB1107200)the National Natural Science Foundation of China (91750110, 11674130, 61605061, 11674110 and 11874020)+2 种基金the Guangdong Provincial Innovation and Entrepreneurship Project (2016ZT06D081)the Natural Science Foundation of Guangdong Province (2016A030306016, 2016TQ03X981 and 2016A030308010)Pearl River S and T Nova Program of Guangzhou (201806010040)。
文摘The possibility to achieve unprecedented multiplexing of light-matter interaction in nanoscale is of virtue importance from both fundamental science and practical application points of view. Cylindrical vector beams(CVBs) manifested as polarization vortices represent a robust and emerging degree of freedom for information multiplexing with increased capacities. Here, we propose and demonstrate massivelyencoded optical data storage(ODS) by harnessing spatially variant electric fields mediated by segmented CVBs. By tight focusing polychromatic segmented CVBs to plasmonic nanoparticle aggregates, recordhigh multiplexing channels of ODS through different combinations of polarization states and wavelengths have been experimentally demonstrated with a low error rate. Our result not only casts new perceptions for tailoring light-matter interactions utilizing structured light but also enables a new prospective for ultra-high capacity optical memory with minimalist system complexity by combining CVB’s compatibility with fiber optics.
基金the Australian Research Council(ARC)Discovery Early Career Research Award(DECRA-DE 140101056)to Y.W.
文摘Owing to the unique advantages of surface enhanced Raman scattering(SERS)in high sensitivity,specificity,multiplexing capability and photostability,it has been widely used in many applications,among which SERS biosensing and bioimaging are the focus in recent years.The successful applications of SERS for non-invasive biomarker detection and bioimaging under in vitro,in vivo and ex vivo conditions,offer significant clinical information to improve diagnostic and prognostic outcomes.This review provides recent developments and applications of SERS,in particular SERS nanotags in biosensing and bioimaging,describing case studies in which different types of biomarkers have been investigated,as well as outlining future challenges that need to be addressed before SERS sees both pathological and clinical use.
文摘Optical absorption in thin-film solar cells can be improved by using surface plasmons for guiding and confining the light on the nanoscale.We report theoretical and simulation studies of a-Si thin-film solar cells with silver nanocylinders on the surface.We found that surface plasmons increased the cells' spectral response over almost the entire studied solar spectrum.In the ultraviolet range and at wavelengths close to the Si band gap we observed a significant enhancement of the absorption for both thin-film and wafer-based structures.We also performed optimization studies of particle size,inter-particle distance,and dielectric environment,for obtaining maximal absorption within the substrate.A blue-shift of the resonance wavelength with increasing inter-particle distance was observed in the visible range.Cell performance improved at optimal spacing,which strongly depended on the nanoparticle size.Increasing the nanocylinder size was accompanied by the widening of the plasmon resonance band and a red-shift of the plasmon resonance peaks.A weak red-shift and plasmon peak enhancement were observed in the reflectance curve with increasing refractive index of the dielectric spacer.