Nanoporous anodic aluminum oxide (AAO) with uniform and controllable pore diameters and periods over a wide range has been explored for various applications due to relatively easy fabrication processes. Moreover, one ...Nanoporous anodic aluminum oxide (AAO) with uniform and controllable pore diameters and periods over a wide range has been explored for various applications due to relatively easy fabrication processes. Moreover, one of the interesting possibilities afforded by the anodization process is that the anodization can take place on aluminum films with arbitrary shape, such as a section of cylinder or sphere, which has not yet been well studied or applied in nanofabrication. In this paper, we report that highly ordered conical nanohole arrays prepared by the anodization of cylindrical and spherical Al films have been fabricated. As can be seen by scanning electron microscopy (SEM), straight nanohole arrays have been grown along the radical directions of the cylindrical or spherical alumina membrane without bending or branching at all, the diameter of the conical nanoholes and the diameter change along individual channels can be tuned by changing the curvature of the membrane. These new types of templates may open new opportunities in optical, electronic and electrochemical applications.展开更多
The perovskite solar cells have been intensively investigated these years due to their premium electrical and optical properties as well as huge potential for application.In order to further increase the power convers...The perovskite solar cells have been intensively investigated these years due to their premium electrical and optical properties as well as huge potential for application.In order to further increase the power conversion efficiency(PCE) of the thin film perovskite solar cells, light management should be taken into consideration. Herein, we apply a lithography method to transfer randomly distributed polystyrene(PS) nanospheres into the electron transporting SnO_(2) layer, by means of which, a nanoholes structure is formed. Finally, we get a nanostructured perovskite layer under low temperature(less than 150 ℃).The depth of SnO_(2) nanoholes is around 60 nm when the device is fabricated with 300-nm PS, and 150 nm in depth when 500-nm PS is used. The device gains PCE of 17.97%,which is 12.3% higher than that with planar electrontransporting SnO_(2) layer and 300-nm CH_(3)NH_(3)PbI_(3) layer.Our findings provide an applicable method to improve the light absorption, which can not only make the absorbing layer of lead-based perovskite solar cells thinner to help decrease the content of lead, but also increase the PCE of non-lead perovskite devices.展开更多
This paper investigates the steady-state thermoelastic problem of a circular nanohole embedded in an infinitely large elastic plane subjected to a uniform far-field heat flux.A lowly conductive surface model is used t...This paper investigates the steady-state thermoelastic problem of a circular nanohole embedded in an infinitely large elastic plane subjected to a uniform far-field heat flux.A lowly conductive surface model is used to account for the effects of surface phonon scattering,while the complete Gurtin–Murdoch model is utilized to characterize the effects of surface tension and surface elasticity.The closed-form solution to the temperature and stress field surrounding the hole is derived in the context of complex variable methods.Several numerical examples are presented to analyze the influence of surface effects on thermal stress fields.It is shown that surface effects induce notable increases in normal and shear stresses around the hole.Specifically,all three stress components(hoop,normal,and shear)in the vicinity of the hole exhibit substantial augmentation with increasing surface tension and surface modulus.In particular,it is found that the presence of surface effects amplifies the variation in stress gradients and intensifies stress concentration around the hole.展开更多
Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to...Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to harvest ambient energy under low/high temperature and relative humidity(RH)conditions.Finite element method simulation of N doped 4H-SiC NHAs in compression mode is developed to evaluate the relationship between nanohole diameter and piezoelectric performance.The density of short circuit current of the assembled PENG reaches 313 nA cm^(-2),which is 1.57 times the output of PENG based on N doped 4H-SiC nanowire arrays.The enhancement can be attributed to the existence of nanohole sidewalls in NHAs.All-weather service capability of the PENG is verified after being treated at-80/80℃and 0%/100%RH for 50 days.The PENG is promising to be widely used in practice worldwide to harvest biomechanical energy and mechanical energy.展开更多
The effective propagation constants of plane longitudinal and shear waves in nanoporous material with random distributed parallel cylindrical nanoholes are studied. The surface elastic theory is used to consider the s...The effective propagation constants of plane longitudinal and shear waves in nanoporous material with random distributed parallel cylindrical nanoholes are studied. The surface elastic theory is used to consider the surface stress effects and to derive the nontraditional boundary condition on the surface of nanoholes. The plane wave expansion method is used to obtain the scattering waves from the single nanohole. The multiple scattering effects are taken into consideration by summing the scat- tered waves from all scatterers and performing the configuration averaging of random distributed scatterers. The effective propagation constants of coherent waves along with the associated dynamic effective elastic modulus are numerically evaluat- ed. The influences of surface stress are discussed based on the numerical results.展开更多
The transmission characteristics of a metallic film with subwavelength ellipsoid nanohole arrays are investigated by using the three-dimensional finite-difference time-domain (3D-FDTD) method. The extraordinary transm...The transmission characteristics of a metallic film with subwavelength ellipsoid nanohole arrays are investigated by using the three-dimensional finite-difference time-domain (3D-FDTD) method. The extraordinary transmission is attributed to the collaboration of localized waveguide resonance and surface plasmon resonance. The influences of the lattice constant and the hole shape on the transmission are studied. By analyzing the picture of electric field and electromagnetic energy distribution, we show the mechanisms of the two different resonances: Localized waveguide resonance mode can be confined inside the ellipsoid holes region, while electric field and electromagnetic energy are localized separately at the two ends of ellipsoid holes for the surface plasma resonance mode.展开更多
In this paper,the study of using masks to directly generate large area,highly ordered and periodical nanostructure has been exhibited.Periodic Au nano-discs(NDs)arrays have been fabricated on top of graphene by using ...In this paper,the study of using masks to directly generate large area,highly ordered and periodical nanostructure has been exhibited.Periodic Au nano-discs(NDs)arrays have been fabricated on top of graphene by using holey SigN4 mask which is directly fixed on top of graphene and Au metal is deposited through the holes in mask by thermal evaporation method under vacuum condition.This fabrication method provides an easy,fast and cost efficiency way to generate periodical nanostructure.Also,Au nanoholes(NHs)structure has been studied by using holey SigN4 as a template.The surface-enhanced Raman scattering(SERS)sensitvities of periodical Au NDs/graphene and graphene/Au NHs hybrid structures have been systematically studied.The internal mechanisms could be explained by chemical mechanism effect of graphene and electromagnetic mechanism effect of metallic nano-structures.The enhancement factors have been systematically investigated by varying the diameter and the thickness of Au discs and Au NHs.Raman mappings of Au NDs with 2.5 um diameter ilustrate that the larger SERS enhancements exist in the rim of NDs which has good agreement with the electric field simulation result.The SERE enhancement factors of fluorescein obtained from Au NDs/graphene substrates shows an improvement factor of 500%in comparison of graphene substrate.The calculated SERS enhancement factors of graphene/Au NHs achieve 1,200%in comparison of graphene/planar Au film substrate.展开更多
Surface plasmon resonance(SPR) nanosensors based on metallic nanohole arrays have been widely reported to detect binding interactions in biological specimens. A simple and effective method for constructing nanoscale a...Surface plasmon resonance(SPR) nanosensors based on metallic nanohole arrays have been widely reported to detect binding interactions in biological specimens. A simple and effective method for constructing nanoscale arrays is essential for the development of SPR nanosensors. In this work, we report a one-step method to fabricate nanohole arrays by thermal nanoimprinting in the matrix of IPS(Intermediate Polymer Stamp). No additional etching process or supporting substrate is required. The preparation process is simple, time-saving and compatible for roll-to-roll process, potentially allowing mass production. Moreover, the nanohole arrays were integrated into detection platform as SPR sensors to investigate different types of biological binding interactions. The results demonstrate that our one-step method can be used to efficiently fabricate large-area and uniform nanohole arrays for biochemical sensing.展开更多
Aluminium nanohole arrays with fixed diameter were fabricated by focused ion beam and the periodicities were turned.Aluminium nanohole arrays enhanced resonance Raman scattering spectra in the near ultraviolet region ...Aluminium nanohole arrays with fixed diameter were fabricated by focused ion beam and the periodicities were turned.Aluminium nanohole arrays enhanced resonance Raman scattering spectra in the near ultraviolet region were studied experimentally and theoretically,which revealed that the SERRS enhancement factor was as high as 6 orders.展开更多
Since the discovery of the extraordinary optical transmission phenomenon,nanohole arrays have attracted much attention and been widely applied in sensing.However,their typical fabrication process,utilizing photolithog...Since the discovery of the extraordinary optical transmission phenomenon,nanohole arrays have attracted much attention and been widely applied in sensing.However,their typical fabrication process,utilizing photolithographic top-down manufacturing technologies,has intrinsic drawbacks including the high costs,time consumption,small footprint,and low throughput.This study presented a low-cost,high-throughput,and scalable method for fabricating centimeter-scale(1×2 cm2)nanohole arrays using the improved nanosphere lithography.The large-scale close-packed polystyrene monolayers obtained by the hemispherical-depression-assisted self-assembly method were employed as colloidal masks for the nanosphere lithography,and the nanohole diameter was tuned from 233 nm to 346 nm with a fixed period of 420 nm via plasma etching.The optical properties and sensing performance of the nanohole arrays were investigated,and two transmission dips were observed due to the resonant coupling of plasmonic modes.Both dips were found to be sensitive to the surrounding environment,and the maximum bulk refractive index sensitivity was up to 162.1 nm/RIU with a 233 nm hole diameter.This study offered a promising approach for fabricating large-scale highly ordered nanohole arrays with various periods and nanohole diameters that could be used for the development of low-cost and high-throughput on-chip plasmonic sensors.展开更多
Structural colors with high saturation,large gamut,high resolution,and tunable color are expected in practical applications.This work explores the generation of tunable structural color based on transmission metasurfa...Structural colors with high saturation,large gamut,high resolution,and tunable color are expected in practical applications.This work explores the generation of tunable structural color based on transmission metasurfaces.The designed metasurfaces consist of rectangular nanoholes etched in silver film,which is deposited on the stretchable polydimethylsiloxane(PDMS)substrate.The smaller separation of adjacent nanoholes makes the resolution of metasurface reach 63,500 dpi.The color gamut of the nanostructures reaches 146.9%sRGB.We also perform a comparison with the case on the glass substrate and analyze the incident polarization condition and the coating film of polymethyl methacrylate(PMMA).The ultra-thin structure,high resolution,highperformance structural colors,and convenient transmission mode provide broad application prospects for metasurfaces in color displaying,color printing,and color holographic imaging.展开更多
Elliptical metallic nanohole arrays possess much higher transmission and enhanced sensitivity compared with circular nanohole arrays.However,fabricating elliptical metallic nanohole arrays in large area with highly tu...Elliptical metallic nanohole arrays possess much higher transmission and enhanced sensitivity compared with circular nanohole arrays.However,fabricating elliptical metallic nanohole arrays in large area with highly tunable aspect ratio remains a challenge.Herein,a brand-new method combining stretchable imprinting with colloidal lithography is figured out to fabricate deep-elliptical-silver-nanowell arrays (d-EAgNWAs).In this method,large area highly ordered silicon nanopillar arrays fabricated by colloidal lithography were taken as a master to transfer large area polydimethylsiloxane (PDMS) nanohole arrays.Benefit from the high elasticity of PDMS mold,the aspect ratio of d-EAgNWAs achieved can be facilely regulated from 1.7 to 5.0.Through optimization of polarization direction and the structural parameters including nanowell depth,aspect ratio,and hole size,the sensing performance of d-EAgNWAs was finally improved up to 1,414.1 nm/RlU.The best sensing behaved d-EAgNWAs were employed as an immunoassay platform finally to prove their great potential in label-free biosensing.展开更多
Large-area deep-silver-nanowell arrays （d-AgNWAs） for plasmonic sensing were manufactured by combining colloidal lithography with metal deposition. In contrast to most previous studies, we shed light on the outstand...Large-area deep-silver-nanowell arrays （d-AgNWAs） for plasmonic sensing were manufactured by combining colloidal lithography with metal deposition. In contrast to most previous studies, we shed light on the outstanding sensitivity afforded by deep metallic nanowells （up to 400 nm in depth）. Using gold nanohole arrays as a mask, a silicon substrate was etched into deep silicon nanowells, which acted as a template for subsequent Ag deposition, resulting in the formation of d-AgNWAs. Various geometric parameters were separately tailored to study the changes in the optical performance and further optimize the sensing ability of the structure. After several rounds of selection, the best sensing d-AgNWA, which had a Ag thickness of 400 nm, template depth of 400 nm, hole diameter of 504 nm, and period of 1 ~m, was selected. It had a sensitivity of 933 nm.RIU-1, which is substantially higher than those of most common thin metallic nanohole arrays. As a proof of concept, the as-prepared structure was employed as a substrate for an antigen-antibody recognition immunoassay, which indicates its great potential for label-free real-time biosensing.展开更多
Surface plasmon resonance(SPR)sensors are based on photon-excited surface charge density oscillations confined at metal-dielectric interfaces,which makes them highly sensitive to biological or chemical molecular bindi...Surface plasmon resonance(SPR)sensors are based on photon-excited surface charge density oscillations confined at metal-dielectric interfaces,which makes them highly sensitive to biological or chemical molecular bindings to functional metallic surfaces.Metal nanostructures further concentrate surface plasmons into a smaller area than the diffraction limit,thus strengthening photon-sample interactions.However,plasmonic sensors based on intensity detection provide limited resolution with long acquisition time owing to their high vulnerability to environmental and instrumental noises.Here,we demonstrate fast and precise detection of noble gas dynamics at single molecular resolution via frequency-comb-referenced plasmonic phase spectroscopy.The photon-sample interaction was enhanced by a factor of 3,852 than the physical sample thickness owing to plasmon resonance and thermophoresis-assisted optical confinement effects.By utilizing a sharp plasmonic phase slope and a high heterodyne information carrier,a small atomic-density modulation was clearly resolved at 5 Hz with a resolution of 0.06 Ar atoms per nano-hole(in 10^(11)RIU)in Allan deviation at 0.2 s;a faster motion up to 200 Hz was clearly resolved.This fast and precise sensing technique can enable the in-depth analysis of fast fluid dynamics with the utmost resolution for a better understanding of biomedical,chemical,and physical events and interactions.展开更多
文摘Nanoporous anodic aluminum oxide (AAO) with uniform and controllable pore diameters and periods over a wide range has been explored for various applications due to relatively easy fabrication processes. Moreover, one of the interesting possibilities afforded by the anodization process is that the anodization can take place on aluminum films with arbitrary shape, such as a section of cylinder or sphere, which has not yet been well studied or applied in nanofabrication. In this paper, we report that highly ordered conical nanohole arrays prepared by the anodization of cylindrical and spherical Al films have been fabricated. As can be seen by scanning electron microscopy (SEM), straight nanohole arrays have been grown along the radical directions of the cylindrical or spherical alumina membrane without bending or branching at all, the diameter of the conical nanoholes and the diameter change along individual channels can be tuned by changing the curvature of the membrane. These new types of templates may open new opportunities in optical, electronic and electrochemical applications.
基金financially supported by the National Natural Science Foundation of China (Nos.11674004,61935016 and 61775004)the National Key R&D Program of China (No.2016YFB0401003)the Science and Technology Planning Project of Guangdong Province,China (No.2017B090904021)。
文摘The perovskite solar cells have been intensively investigated these years due to their premium electrical and optical properties as well as huge potential for application.In order to further increase the power conversion efficiency(PCE) of the thin film perovskite solar cells, light management should be taken into consideration. Herein, we apply a lithography method to transfer randomly distributed polystyrene(PS) nanospheres into the electron transporting SnO_(2) layer, by means of which, a nanoholes structure is formed. Finally, we get a nanostructured perovskite layer under low temperature(less than 150 ℃).The depth of SnO_(2) nanoholes is around 60 nm when the device is fabricated with 300-nm PS, and 150 nm in depth when 500-nm PS is used. The device gains PCE of 17.97%,which is 12.3% higher than that with planar electrontransporting SnO_(2) layer and 300-nm CH_(3)NH_(3)PbI_(3) layer.Our findings provide an applicable method to improve the light absorption, which can not only make the absorbing layer of lead-based perovskite solar cells thinner to help decrease the content of lead, but also increase the PCE of non-lead perovskite devices.
基金supported by the National Natural Science Foundation of China(Grant No.11902116)the Natural Science Foundation of Guangdong Province(Grant No.2022A1515011773)the Natural Science Foundation of Guangzhou City(Grant No.202201010317).
文摘This paper investigates the steady-state thermoelastic problem of a circular nanohole embedded in an infinitely large elastic plane subjected to a uniform far-field heat flux.A lowly conductive surface model is used to account for the effects of surface phonon scattering,while the complete Gurtin–Murdoch model is utilized to characterize the effects of surface tension and surface elasticity.The closed-form solution to the temperature and stress field surrounding the hole is derived in the context of complex variable methods.Several numerical examples are presented to analyze the influence of surface effects on thermal stress fields.It is shown that surface effects induce notable increases in normal and shear stresses around the hole.Specifically,all three stress components(hoop,normal,and shear)in the vicinity of the hole exhibit substantial augmentation with increasing surface tension and surface modulus.In particular,it is found that the presence of surface effects amplifies the variation in stress gradients and intensifies stress concentration around the hole.
基金This work was supported by the National Science Fund for Distinguished Young Scholars(No.52025041)the National Natural Science Foundation of China(No.51974021,51902020,51904021)+2 种基金the Fundamental Research Funds for the Central Universities of NO.FRF-TP-18-045A1 and FRF-TP-19-004B2Zthe National Postdoctoral Program for Innovative Talents(BX20180034)This project is supported by open foundation of Guangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials,Guangxi University(Grant No.2021GXYSOF12).
文摘Ultra-stable piezoelectric nanogenerator(PENG)driven by environmental actuation sources with all-weather service capability is highly desirable.Here,the PENG based on N doped 4H-SiC nanohole arrays(NHAs)is proposed to harvest ambient energy under low/high temperature and relative humidity(RH)conditions.Finite element method simulation of N doped 4H-SiC NHAs in compression mode is developed to evaluate the relationship between nanohole diameter and piezoelectric performance.The density of short circuit current of the assembled PENG reaches 313 nA cm^(-2),which is 1.57 times the output of PENG based on N doped 4H-SiC nanowire arrays.The enhancement can be attributed to the existence of nanohole sidewalls in NHAs.All-weather service capability of the PENG is verified after being treated at-80/80℃and 0%/100%RH for 50 days.The PENG is promising to be widely used in practice worldwide to harvest biomechanical energy and mechanical energy.
基金the National Natural Science Foundation of China (Grant Nos. 10972029 and 40906044)the Youth Scientific Research Foundation PLA University of Science and Technology (Grant No. 20110510)
文摘The effective propagation constants of plane longitudinal and shear waves in nanoporous material with random distributed parallel cylindrical nanoholes are studied. The surface elastic theory is used to consider the surface stress effects and to derive the nontraditional boundary condition on the surface of nanoholes. The plane wave expansion method is used to obtain the scattering waves from the single nanohole. The multiple scattering effects are taken into consideration by summing the scat- tered waves from all scatterers and performing the configuration averaging of random distributed scatterers. The effective propagation constants of coherent waves along with the associated dynamic effective elastic modulus are numerically evaluat- ed. The influences of surface stress are discussed based on the numerical results.
基金Supported by the National Natural Science Foundation of China (Grant No. 60708014)the Distinguished Youth Foundation of Hunan Province (Grant No. 03JJY1008)+1 种基金the Science Foundation for Post-doctorate of China (Grant No. 2004035083)the Natural Science Foundation of Hunan Province (Grant No. 06JJ20034)
文摘The transmission characteristics of a metallic film with subwavelength ellipsoid nanohole arrays are investigated by using the three-dimensional finite-difference time-domain (3D-FDTD) method. The extraordinary transmission is attributed to the collaboration of localized waveguide resonance and surface plasmon resonance. The influences of the lattice constant and the hole shape on the transmission are studied. By analyzing the picture of electric field and electromagnetic energy distribution, we show the mechanisms of the two different resonances: Localized waveguide resonance mode can be confined inside the ellipsoid holes region, while electric field and electromagnetic energy are localized separately at the two ends of ellipsoid holes for the surface plasma resonance mode.
基金China Scholarship Council,Chinese National Natural Science and MINISTERIO DE ECONOMIA,INDUSTRIA Y COMPETITIVIDAD with the funding numbers of 201606180013,51520105003 and MAT2017-89868-P,respectively.
文摘In this paper,the study of using masks to directly generate large area,highly ordered and periodical nanostructure has been exhibited.Periodic Au nano-discs(NDs)arrays have been fabricated on top of graphene by using holey SigN4 mask which is directly fixed on top of graphene and Au metal is deposited through the holes in mask by thermal evaporation method under vacuum condition.This fabrication method provides an easy,fast and cost efficiency way to generate periodical nanostructure.Also,Au nanoholes(NHs)structure has been studied by using holey SigN4 as a template.The surface-enhanced Raman scattering(SERS)sensitvities of periodical Au NDs/graphene and graphene/Au NHs hybrid structures have been systematically studied.The internal mechanisms could be explained by chemical mechanism effect of graphene and electromagnetic mechanism effect of metallic nano-structures.The enhancement factors have been systematically investigated by varying the diameter and the thickness of Au discs and Au NHs.Raman mappings of Au NDs with 2.5 um diameter ilustrate that the larger SERS enhancements exist in the rim of NDs which has good agreement with the electric field simulation result.The SERE enhancement factors of fluorescein obtained from Au NDs/graphene substrates shows an improvement factor of 500%in comparison of graphene substrate.The calculated SERS enhancement factors of graphene/Au NHs achieve 1,200%in comparison of graphene/planar Au film substrate.
基金financially supported by the National Natural Science Foundation of China (31430061, 61401149, and U1604177)Ministry of Agriculture of China (2016ZX08009-003)the Program of China’s 1000-talents Plan
文摘Surface plasmon resonance(SPR) nanosensors based on metallic nanohole arrays have been widely reported to detect binding interactions in biological specimens. A simple and effective method for constructing nanoscale arrays is essential for the development of SPR nanosensors. In this work, we report a one-step method to fabricate nanohole arrays by thermal nanoimprinting in the matrix of IPS(Intermediate Polymer Stamp). No additional etching process or supporting substrate is required. The preparation process is simple, time-saving and compatible for roll-to-roll process, potentially allowing mass production. Moreover, the nanohole arrays were integrated into detection platform as SPR sensors to investigate different types of biological binding interactions. The results demonstrate that our one-step method can be used to efficiently fabricate large-area and uniform nanohole arrays for biochemical sensing.
基金supported by the National Basic Research Program of China(Grant No.2012CB626801)the National Natural Science Foundation of China(Grant No.11274057)+5 种基金the Program for New Century Excellent Talents in University(Grant No.NCET-13-0702)the Science and Technology Project of Liaoning Province(Grant No.2012222009)the Fundamental Research Funds for the Central Universities(Grant No.DC12010117)the Program for Liaoning Excellent Talents in University(LNET)(Grant No.LJQ2012112)the Science and Technique Foundation of Dalian(Grant Nos.2012J21DW016 and 2013A14GX040)the Science and Technique Foundation of Jinzhou New District(Grant No.2012-A1-051)
文摘Aluminium nanohole arrays with fixed diameter were fabricated by focused ion beam and the periodicities were turned.Aluminium nanohole arrays enhanced resonance Raman scattering spectra in the near ultraviolet region were studied experimentally and theoretically,which revealed that the SERRS enhancement factor was as high as 6 orders.
基金supported by the National Natural Science Foundation of China(Grant Nos.62375036,62005034,62171076,and 61727816)Liaoning Cancer Hospital&Institute“Oncology+”Funds(Grant No.2024-ZLKF-34)Fundamental Research Funds for the Central Universities(Grant No.DUT21RC(3)080).
文摘Since the discovery of the extraordinary optical transmission phenomenon,nanohole arrays have attracted much attention and been widely applied in sensing.However,their typical fabrication process,utilizing photolithographic top-down manufacturing technologies,has intrinsic drawbacks including the high costs,time consumption,small footprint,and low throughput.This study presented a low-cost,high-throughput,and scalable method for fabricating centimeter-scale(1×2 cm2)nanohole arrays using the improved nanosphere lithography.The large-scale close-packed polystyrene monolayers obtained by the hemispherical-depression-assisted self-assembly method were employed as colloidal masks for the nanosphere lithography,and the nanohole diameter was tuned from 233 nm to 346 nm with a fixed period of 420 nm via plasma etching.The optical properties and sensing performance of the nanohole arrays were investigated,and two transmission dips were observed due to the resonant coupling of plasmonic modes.Both dips were found to be sensitive to the surrounding environment,and the maximum bulk refractive index sensitivity was up to 162.1 nm/RIU with a 233 nm hole diameter.This study offered a promising approach for fabricating large-scale highly ordered nanohole arrays with various periods and nanohole diameters that could be used for the development of low-cost and high-throughput on-chip plasmonic sensors.
基金National Natural Science Foundation of China(10874105)Natural Science Foundation of Shandong Province(ZR2020KA009)。
文摘Structural colors with high saturation,large gamut,high resolution,and tunable color are expected in practical applications.This work explores the generation of tunable structural color based on transmission metasurfaces.The designed metasurfaces consist of rectangular nanoholes etched in silver film,which is deposited on the stretchable polydimethylsiloxane(PDMS)substrate.The smaller separation of adjacent nanoholes makes the resolution of metasurface reach 63,500 dpi.The color gamut of the nanostructures reaches 146.9%sRGB.We also perform a comparison with the case on the glass substrate and analyze the incident polarization condition and the coating film of polymethyl methacrylate(PMMA).The ultra-thin structure,high resolution,highperformance structural colors,and convenient transmission mode provide broad application prospects for metasurfaces in color displaying,color printing,and color holographic imaging.
基金National Natural Science Foundation of China (No. 51433003)National Key Research and Development Program of China (No. 2016YFB0401701)JLU Science and Technology Innovative Research Team 2017TD-06.
文摘Elliptical metallic nanohole arrays possess much higher transmission and enhanced sensitivity compared with circular nanohole arrays.However,fabricating elliptical metallic nanohole arrays in large area with highly tunable aspect ratio remains a challenge.Herein,a brand-new method combining stretchable imprinting with colloidal lithography is figured out to fabricate deep-elliptical-silver-nanowell arrays (d-EAgNWAs).In this method,large area highly ordered silicon nanopillar arrays fabricated by colloidal lithography were taken as a master to transfer large area polydimethylsiloxane (PDMS) nanohole arrays.Benefit from the high elasticity of PDMS mold,the aspect ratio of d-EAgNWAs achieved can be facilely regulated from 1.7 to 5.0.Through optimization of polarization direction and the structural parameters including nanowell depth,aspect ratio,and hole size,the sensing performance of d-EAgNWAs was finally improved up to 1,414.1 nm/RlU.The best sensing behaved d-EAgNWAs were employed as an immunoassay platform finally to prove their great potential in label-free biosensing.
基金This work was financially supported by the National Basic Research Program of China （973 program, No. 2012CB933800） and the National Natural Science Foundation of China （NSFC, No. 91123031）.
文摘Large-area deep-silver-nanowell arrays （d-AgNWAs） for plasmonic sensing were manufactured by combining colloidal lithography with metal deposition. In contrast to most previous studies, we shed light on the outstanding sensitivity afforded by deep metallic nanowells （up to 400 nm in depth）. Using gold nanohole arrays as a mask, a silicon substrate was etched into deep silicon nanowells, which acted as a template for subsequent Ag deposition, resulting in the formation of d-AgNWAs. Various geometric parameters were separately tailored to study the changes in the optical performance and further optimize the sensing ability of the structure. After several rounds of selection, the best sensing d-AgNWA, which had a Ag thickness of 400 nm, template depth of 400 nm, hole diameter of 504 nm, and period of 1 ~m, was selected. It had a sensitivity of 933 nm.RIU-1, which is substantially higher than those of most common thin metallic nanohole arrays. As a proof of concept, the as-prepared structure was employed as a substrate for an antigen-antibody recognition immunoassay, which indicates its great potential for label-free real-time biosensing.
基金supported by the National Research Foundation of the Republic of Korea(NRF-2019K1A3A1A20092429,NRF-2020R1A2C2102338,NRF-2022M1A3C2069728RS-2024-00401786)+2 种基金the Basic Research Program(NK236C)funded by the Korea Institute of Machinery and Materials(KIMM)supported by the KAIST UP Program and the Commercializations Promotion Agency for R&D Outcomes(COMPA)under grant RS-2023-00260002 and the Ministry of Small and Medium-sized Enterprises(SMEs)and Startups under grant RCMS-S3207602support of time and facilities from Ho Chi Minh City University of Technology(HCMUT),Viet Nam National University Ho Chi Minh City(VNU-HCM)。
文摘Surface plasmon resonance(SPR)sensors are based on photon-excited surface charge density oscillations confined at metal-dielectric interfaces,which makes them highly sensitive to biological or chemical molecular bindings to functional metallic surfaces.Metal nanostructures further concentrate surface plasmons into a smaller area than the diffraction limit,thus strengthening photon-sample interactions.However,plasmonic sensors based on intensity detection provide limited resolution with long acquisition time owing to their high vulnerability to environmental and instrumental noises.Here,we demonstrate fast and precise detection of noble gas dynamics at single molecular resolution via frequency-comb-referenced plasmonic phase spectroscopy.The photon-sample interaction was enhanced by a factor of 3,852 than the physical sample thickness owing to plasmon resonance and thermophoresis-assisted optical confinement effects.By utilizing a sharp plasmonic phase slope and a high heterodyne information carrier,a small atomic-density modulation was clearly resolved at 5 Hz with a resolution of 0.06 Ar atoms per nano-hole(in 10^(11)RIU)in Allan deviation at 0.2 s;a faster motion up to 200 Hz was clearly resolved.This fast and precise sensing technique can enable the in-depth analysis of fast fluid dynamics with the utmost resolution for a better understanding of biomedical,chemical,and physical events and interactions.
