Surface-plasmon（SP） modes triggered on metal nanostructures were strongly coupled to the local restricted electronmagnetic field supported by a Fabry-Perot（F-P） cavity. This hybrid system provided an ideal platfor...Surface-plasmon（SP） modes triggered on metal nanostructures were strongly coupled to the local restricted electronmagnetic field supported by a Fabry-Perot（F-P） cavity. This hybrid system provided an ideal platform to study the interaction between SP and F-P resonators on nanoscales. However, the time-resolved transient energy transfer process is far from resolved. In this letter, we addressed this question by time-resolved femtosecond pump-probe technology and readily observed the transient energy transfer between SP and nanocavity resonant ener- gy. The interaction resulted in the emergence of hybrid splitting mode and the oscillating dynamics between upper and lower polariton branch（the split hybrid states）. Our work may provide a well comprehension of strong coupling between SP modes and F-P resonator modes, and lay some groundwork for many future photonic applications.展开更多
A tunable plasmonic waveguide via gold nanoshells immerged in a silica base is proposed and simulated by using the finite difference time-domain （FDTD） method. For waveguides based on near-field coupling, transmissi...A tunable plasmonic waveguide via gold nanoshells immerged in a silica base is proposed and simulated by using the finite difference time-domain （FDTD） method. For waveguides based on near-field coupling, transmission frequencies can be tuned in a wide region from 660 to 900 nm in wavelength by varying shell thicknesses. After exploring the steady distributions of electric fields in these waveguides, we find that their decay lengths are about 5.948-12.83 dB/1000 nm, which is superior to the decay length （8.947 dB/1000 nm） of a gold nanosphere plasmonic waveguide. These excellent tunability and transmittability are mainly due to the unique hollow structure. These gold nanoshell waveguides should be fabricated in laboratory.展开更多
Plasmon resonance energy transfer(PRET) occurs between the plasmonic nanoparticles(NPs) and organic dyes forming donor-acceptor pairs, which has great potential in quantitative analytical chemistry because of its exce...Plasmon resonance energy transfer(PRET) occurs between the plasmonic nanoparticles(NPs) and organic dyes forming donor-acceptor pairs, which has great potential in quantitative analytical chemistry because of its excellent sensitivity under dark-field microscopy(DFM). Herein, we introduce supramolecular β-cyclodextrin(β-CD) to design a host-guest recognition plasmonic nano-structure modified gold nanoparticles(GNPs), while GNPs and rhodamine molecule(RB) act as the donor and acceptor, respectively. In the presence of the target cholesterol, due to the stronger binding of cholesterol with β-CD, RB molecules are released, inducing the inhibition of PRET, as well as the increase of the scattering intensity of GNPs.The proposed strategy achieves a linear range from 0.02 μmol/L to 2.0 μmol/L for cholesterol detection,and reaches a limit of detection(LOD) of 6.7 nmol/L. This host-guest recognition strategy can easily integrate receptor-donor pair into one nanoparticle, which simplifies the construction of the PRET platform,and further provides an effective approach for PRET-based analytical applications. Afterwards, the proposed PRET strategy was successfully applied for the detection of cholesterol in serum samples with high sensitivity and specificity. The proposed method provides an effective clinically potential means for the detection of cholesterol and other disease-related biomarkers.展开更多
Self-assembled chain-like nanostructures utilizing localized surface plasmon resonance(LSPR)effect could enhance the local electromagnetic field for energy transfer,which provides huge structural advantages for some t...Self-assembled chain-like nanostructures utilizing localized surface plasmon resonance(LSPR)effect could enhance the local electromagnetic field for energy transfer,which provides huge structural advantages for some transmission-related applications such as photocatalysis.In this work,the dual-chain structure of Au chain wrapped CuS(denoted as Au Chain@CuS)was successfully synthesized by the one-step hydrothermal method.Namely,L-cysteine is used as the sulfur source and linking agent,and copper nitrate is the precursor of copper ions,forming the dual-chain driven by 15 nm uniform Au seeds.Transient absorption spectroscopy(TAS)and finite-difference-time-domain(FDTD)simulation exhibited the highly intensive electromagnetic field around the self-assembly chain,the raised formation and transfer rate of electron–hole pairs between the Au chain and surrounding CuS chain.Meanwhile,it shows an excellent photodegradation activity on dye rhodamine B(RhB).Within 1 h under simulated sunlight,the degradation rate reached 98.81%in Au Chain@CuS,which is 2.27 times higher compared to the bare CuS.The enhanced performance is mainly attributed to the near-field enhancement effect induced by LSPR,as well as the benefits of more effective resonance energy transfer(RET).This research comprehensively shows the electromagnetic field in LSPR metal chain is more intensive by order of magnitude relative to the isolated particles.Simultaneously the continuous CuS chain wrapped outside of the LSPR source effectively absorbs and utilizes the plasmonic energy,then promotes the formation of the photo-generated charge,thus increasing the photocatalytic performance.This founding of wrapped coupled-metal dual-chain provides a promising candidate for the highly efficient photocatalysts.展开更多
Fluorescent rare-earth ions are useful for efficient energy transfer via multi- channels with different properties. Tuning these transfer processes in functional rare-earth materials has attracted considerable attenti...Fluorescent rare-earth ions are useful for efficient energy transfer via multi- channels with different properties. Tuning these transfer processes in functional rare-earth materials has attracted considerable attention to satisfy the various demands of diverse practical applications. In this study, strong tunabilities of cooperative energy transfer and nonlinear upconversion emissions are realized using （Yb3＋, Er3＋）/NaYF4 nanocrystals with and without doped Mn2~ ions by adopting a plasmonic nanocavity composed of a silver nanorod array. The plasmon nanocavity can not only increase the energy transfer between Mn2＋ and （Yb3＋, Er3＋） but also significantly enhance the radiative emission. This reveals a prominent nonlinear gain in the nanocavity nanosystems. These observations suggest the prospective applications in the design and preparation of rare-earth nanocrystals with excellent tunabilities of multiple functionalities.展开更多
Among the many novel photocatalytic systems developed in very recent years,plasmonic photocatalytic composites possess great potential for use in applications and are one of the most intensively investigated photocata...Among the many novel photocatalytic systems developed in very recent years,plasmonic photocatalytic composites possess great potential for use in applications and are one of the most intensively investigated photocatalytic systems owing to their high solar energy utilization efficiency.In these composites,the plasmonic nanoparticles(PNPs)efficiently absorb solar light through localized surface plasmon resonance and convert it into energetic electrons and holes in the nearby semiconductor.This energy transfer from PNPs to semiconductors plays a decisive role in the overall photocatalytic performance.Thus,the underlying physical mechanism is of great scientific and technological importance and is one of the hottest topics in the area of plasmonic photocatalysts.In this review,we examine the very recent advances in understanding the energy transfer process in plasmonic photocatalytic composites,describing both the theoretical basis of this process and experimental demonstrations.The factors that affect the energy transfer efficiencies and how to improve the efficiencies to yield better photocatalytic performance are also discussed.Furthermore,comparisons are made between the various energy transfer processes,emphasizing their limitations/benefits for efficient operation of plasmonic photocatalysts.展开更多
基金Supported by the National Basic Research Program of ChinafNos.2014CB921302, 2011CB013003）, the National Natural Science Foundation, of China（Nos.21273096, 61378053） and the Doctoral Fund of Ministry of Education of China（No.20130061110048）.
文摘Surface-plasmon（SP） modes triggered on metal nanostructures were strongly coupled to the local restricted electronmagnetic field supported by a Fabry-Perot（F-P） cavity. This hybrid system provided an ideal platform to study the interaction between SP and F-P resonators on nanoscales. However, the time-resolved transient energy transfer process is far from resolved. In this letter, we addressed this question by time-resolved femtosecond pump-probe technology and readily observed the transient energy transfer between SP and nanocavity resonant ener- gy. The interaction resulted in the emergence of hybrid splitting mode and the oscillating dynamics between upper and lower polariton branch（the split hybrid states）. Our work may provide a well comprehension of strong coupling between SP modes and F-P resonator modes, and lay some groundwork for many future photonic applications.
基金supported by the National Natural Science Foundation of China (Grants Nos 10674009,10521002 and 10434020)the National Key Basic Research Program of China (Grant No 2007CB307001)
文摘A tunable plasmonic waveguide via gold nanoshells immerged in a silica base is proposed and simulated by using the finite difference time-domain （FDTD） method. For waveguides based on near-field coupling, transmission frequencies can be tuned in a wide region from 660 to 900 nm in wavelength by varying shell thicknesses. After exploring the steady distributions of electric fields in these waveguides, we find that their decay lengths are about 5.948-12.83 dB/1000 nm, which is superior to the decay length （8.947 dB/1000 nm） of a gold nanosphere plasmonic waveguide. These excellent tunability and transmittability are mainly due to the unique hollow structure. These gold nanoshell waveguides should be fabricated in laboratory.
基金supported by the National Natural Science Foundation of China (Nos. 22034003 and 22074063)Fundamental Research Funds for the Central Universities (No. 2022300285)。
文摘Plasmon resonance energy transfer(PRET) occurs between the plasmonic nanoparticles(NPs) and organic dyes forming donor-acceptor pairs, which has great potential in quantitative analytical chemistry because of its excellent sensitivity under dark-field microscopy(DFM). Herein, we introduce supramolecular β-cyclodextrin(β-CD) to design a host-guest recognition plasmonic nano-structure modified gold nanoparticles(GNPs), while GNPs and rhodamine molecule(RB) act as the donor and acceptor, respectively. In the presence of the target cholesterol, due to the stronger binding of cholesterol with β-CD, RB molecules are released, inducing the inhibition of PRET, as well as the increase of the scattering intensity of GNPs.The proposed strategy achieves a linear range from 0.02 μmol/L to 2.0 μmol/L for cholesterol detection,and reaches a limit of detection(LOD) of 6.7 nmol/L. This host-guest recognition strategy can easily integrate receptor-donor pair into one nanoparticle, which simplifies the construction of the PRET platform,and further provides an effective approach for PRET-based analytical applications. Afterwards, the proposed PRET strategy was successfully applied for the detection of cholesterol in serum samples with high sensitivity and specificity. The proposed method provides an effective clinically potential means for the detection of cholesterol and other disease-related biomarkers.
基金This research was funded by the National Key R&D Program of China(No.2018YFA0209200).
文摘Self-assembled chain-like nanostructures utilizing localized surface plasmon resonance(LSPR)effect could enhance the local electromagnetic field for energy transfer,which provides huge structural advantages for some transmission-related applications such as photocatalysis.In this work,the dual-chain structure of Au chain wrapped CuS(denoted as Au Chain@CuS)was successfully synthesized by the one-step hydrothermal method.Namely,L-cysteine is used as the sulfur source and linking agent,and copper nitrate is the precursor of copper ions,forming the dual-chain driven by 15 nm uniform Au seeds.Transient absorption spectroscopy(TAS)and finite-difference-time-domain(FDTD)simulation exhibited the highly intensive electromagnetic field around the self-assembly chain,the raised formation and transfer rate of electron–hole pairs between the Au chain and surrounding CuS chain.Meanwhile,it shows an excellent photodegradation activity on dye rhodamine B(RhB).Within 1 h under simulated sunlight,the degradation rate reached 98.81%in Au Chain@CuS,which is 2.27 times higher compared to the bare CuS.The enhanced performance is mainly attributed to the near-field enhancement effect induced by LSPR,as well as the benefits of more effective resonance energy transfer(RET).This research comprehensively shows the electromagnetic field in LSPR metal chain is more intensive by order of magnitude relative to the isolated particles.Simultaneously the continuous CuS chain wrapped outside of the LSPR source effectively absorbs and utilizes the plasmonic energy,then promotes the formation of the photo-generated charge,thus increasing the photocatalytic performance.This founding of wrapped coupled-metal dual-chain provides a promising candidate for the highly efficient photocatalysts.
文摘Fluorescent rare-earth ions are useful for efficient energy transfer via multi- channels with different properties. Tuning these transfer processes in functional rare-earth materials has attracted considerable attention to satisfy the various demands of diverse practical applications. In this study, strong tunabilities of cooperative energy transfer and nonlinear upconversion emissions are realized using （Yb3＋, Er3＋）/NaYF4 nanocrystals with and without doped Mn2~ ions by adopting a plasmonic nanocavity composed of a silver nanorod array. The plasmon nanocavity can not only increase the energy transfer between Mn2＋ and （Yb3＋, Er3＋） but also significantly enhance the radiative emission. This reveals a prominent nonlinear gain in the nanocavity nanosystems. These observations suggest the prospective applications in the design and preparation of rare-earth nanocrystals with excellent tunabilities of multiple functionalities.
基金supported by the National Basic Research Program of China(973 program,2013CB632401)the National Science Foundation of China(Grant NOs 11374190 and 21333006)the Taishan Scholar Program of Shandong and 111 Project B13029.
文摘Among the many novel photocatalytic systems developed in very recent years,plasmonic photocatalytic composites possess great potential for use in applications and are one of the most intensively investigated photocatalytic systems owing to their high solar energy utilization efficiency.In these composites,the plasmonic nanoparticles(PNPs)efficiently absorb solar light through localized surface plasmon resonance and convert it into energetic electrons and holes in the nearby semiconductor.This energy transfer from PNPs to semiconductors plays a decisive role in the overall photocatalytic performance.Thus,the underlying physical mechanism is of great scientific and technological importance and is one of the hottest topics in the area of plasmonic photocatalysts.In this review,we examine the very recent advances in understanding the energy transfer process in plasmonic photocatalytic composites,describing both the theoretical basis of this process and experimental demonstrations.The factors that affect the energy transfer efficiencies and how to improve the efficiencies to yield better photocatalytic performance are also discussed.Furthermore,comparisons are made between the various energy transfer processes,emphasizing their limitations/benefits for efficient operation of plasmonic photocatalysts.
