Structures consisting of a planar array of subwavelength metallic bars fabricated on a dielectric substrate are theoretically investigated in order to rotate the polarization of a normally incident terahertz wave in t...Structures consisting of a planar array of subwavelength metallic bars fabricated on a dielectric substrate are theoretically investigated in order to rotate the polarization of a normally incident terahertz wave in the resonance frequency band.We attribute this phenomenon to one component of the terahertz electric field parallel to inclined metallic bars which is reflected strongly due to the terahertz re-radiation from accelerated electrons in the metallic bars,while the other component perpendicular to the bars transmits almost entirely through the structures.By theoretical analysis,we obtain the transmitted-terahertz components polarized in the x-and y-directions,respectively.Further studies indicate polarization of a terahertz wave can be rotated within two specific frequency bands when the terahertz impinges on the double-bar sample.展开更多
The rational design and synthesis of hybrid-type electrode nanomaterials are significant for their diverse applications,including their potential usage as high-efficiency nanoarchitectures for supercapacitors(SCs)as a...The rational design and synthesis of hybrid-type electrode nanomaterials are significant for their diverse applications,including their potential usage as high-efficiency nanoarchitectures for supercapacitors(SCs)as a class of promising energy-storage systems for powering next-generation electric vehicles and electronic devices.Here,we reported a facile and controllable synthesis of core-shell Ni_(3)S_(2)@NiWO_(4)nanoarrays to fabricate a freestanding electrode for hybrid SCs.Impressively,the as-prepared freestanding Ni_(3)S_(2)@NiWO_(4)electrode presents an ultrahigh areal capacity of 2032μA h cm^(-2)at 5 mA cm^(-2),and a capacity retention of 63.6%even when the current density increased up to 50 mA cm^(-2).Remarkably,the Ni_(3)S_(2)@NiWO_(4)nanoarraybased hybrid SC delivers a maximum energy density of 1.283 mW h cm^(-2)at 3.128 mW cm^(-2)and a maximum power density of 41.105 mW cm^(-2)at 0.753 mW h cm^(-2).Furthermore,the hybrid SC exhibits a capacity retention of 89.6%even after continuous 10,000 cycles,proving its superior stability.This study provides a facile pathway to rationally design a variety of core-shell metal nanostructures for high-performance energy storage devices.展开更多
Metallic nanowire arrays （NWAs） possess wide application prospects due to their unique property, and the tailoring of NWAs＇ structure and morphology is of importance since it would significantly influence the per- ...Metallic nanowire arrays （NWAs） possess wide application prospects due to their unique property, and the tailoring of NWAs＇ structure and morphology is of importance since it would significantly influence the per- formance of NWAs. In the present work, the morphology and structure evolution of the NWAs prepared by the newly developed die nanoimprinting technique has been investigated in detail. It was found that increasing pro- cessing temperature, time and pressure could increase the length of the nanowires and change the NWAs＇ morphol- ogy from monodispersed form to aggregated form. Increasing processing time and temperature within the supercooled liquid region would promote crystallization, while increasing processing pressure could suppress the crystallization. This work provided important insights into the structure and morphology evolution, and therefore, the tailoring of metallic NWAs prepared by die nanoimprinting through adjusting the process parameters.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.10804077,10904098 and 11011120242)the National Basic Research Program of China(Grant No.2007CB310408)+2 种基金the Ministry of Education Key Project(Grant No.210002)Beijing Municipal Commission of Education(Grant Nos.KM200910028006 and KM201110028004)Beijing Nova Program and Funding Project for Academic Human Resources Development in Institutions of Higher Learning Under the Jurisdiction of Beijing Municipality
文摘Structures consisting of a planar array of subwavelength metallic bars fabricated on a dielectric substrate are theoretically investigated in order to rotate the polarization of a normally incident terahertz wave in the resonance frequency band.We attribute this phenomenon to one component of the terahertz electric field parallel to inclined metallic bars which is reflected strongly due to the terahertz re-radiation from accelerated electrons in the metallic bars,while the other component perpendicular to the bars transmits almost entirely through the structures.By theoretical analysis,we obtain the transmitted-terahertz components polarized in the x-and y-directions,respectively.Further studies indicate polarization of a terahertz wave can be rotated within two specific frequency bands when the terahertz impinges on the double-bar sample.
基金the National Natural Science Foundation of China(91963113)。
文摘The rational design and synthesis of hybrid-type electrode nanomaterials are significant for their diverse applications,including their potential usage as high-efficiency nanoarchitectures for supercapacitors(SCs)as a class of promising energy-storage systems for powering next-generation electric vehicles and electronic devices.Here,we reported a facile and controllable synthesis of core-shell Ni_(3)S_(2)@NiWO_(4)nanoarrays to fabricate a freestanding electrode for hybrid SCs.Impressively,the as-prepared freestanding Ni_(3)S_(2)@NiWO_(4)electrode presents an ultrahigh areal capacity of 2032μA h cm^(-2)at 5 mA cm^(-2),and a capacity retention of 63.6%even when the current density increased up to 50 mA cm^(-2).Remarkably,the Ni_(3)S_(2)@NiWO_(4)nanoarraybased hybrid SC delivers a maximum energy density of 1.283 mW h cm^(-2)at 3.128 mW cm^(-2)and a maximum power density of 41.105 mW cm^(-2)at 0.753 mW h cm^(-2).Furthermore,the hybrid SC exhibits a capacity retention of 89.6%even after continuous 10,000 cycles,proving its superior stability.This study provides a facile pathway to rationally design a variety of core-shell metal nanostructures for high-performance energy storage devices.
基金This work was supported by the National Natural Science Foundation of China （51271095 and 51101090）, and PhD Program Foundation of Ministry of Education of China （20120002110038）.
文摘Metallic nanowire arrays （NWAs） possess wide application prospects due to their unique property, and the tailoring of NWAs＇ structure and morphology is of importance since it would significantly influence the per- formance of NWAs. In the present work, the morphology and structure evolution of the NWAs prepared by the newly developed die nanoimprinting technique has been investigated in detail. It was found that increasing pro- cessing temperature, time and pressure could increase the length of the nanowires and change the NWAs＇ morphol- ogy from monodispersed form to aggregated form. Increasing processing time and temperature within the supercooled liquid region would promote crystallization, while increasing processing pressure could suppress the crystallization. This work provided important insights into the structure and morphology evolution, and therefore, the tailoring of metallic NWAs prepared by die nanoimprinting through adjusting the process parameters.
