The CdS/Bi_(2)S_(3) supported three-dimensional(3D)porous faveolate carbon structure(CdS/Bi_(2)S_(3)@C)composite photocatalyst was constructed.Bi_(2)S_(3) nanoparticles are regarded as photothermal agents and pyroelec...The CdS/Bi_(2)S_(3) supported three-dimensional(3D)porous faveolate carbon structure(CdS/Bi_(2)S_(3)@C)composite photocatalyst was constructed.Bi_(2)S_(3) nanoparticles are regarded as photothermal agents and pyroelectric materials to absorb near infrared light(NIR)and convert it into heat.3D porous faveolate of carbon acts as incubator to reduce heat loss and optimize photothermal effects.There is a greater fluctuating temperature difference(ΔΤ)between photothermal effect of Bi_(2)S_(3) and cold photocatalytic system.This enhances the pyroelectric effect that Bi_(2)S_(3) undergoes spontaneous polarization and releases the surface charge.Therefore,the separation of electrons and holes in the CdS photocatalyst can be induced.The COMSOL simulation results show that,the higher pyroelectric potential producted by largerΔΤis more favorable to the photocatalytic process.The hydrogen evolution rate of CdS/Bi_(2)S_(3)@C photocatalyst can reach 5.88 mmol·g^(-1)·h^(-1) with excellent cycle stability.展开更多
Dynamically tunable metasurfaces employing chalcogenide phase-change materials(PCMs)such as Ge_(2)Sb_(2)Te_(5)alloys have garnered significant attention and research efforts.However,the utilization of chalcogenide PCM...Dynamically tunable metasurfaces employing chalcogenide phase-change materials(PCMs)such as Ge_(2)Sb_(2)Te_(5)alloys have garnered significant attention and research efforts.However,the utilization of chalcogenide PCMs in dynamic metasurface devices necessitates protection,owing to their susceptibility to volatilization and oxidation.Conventional protective layer materials such as Al_(2)O_(3),TiO_(2),and SiO_(2)present potential drawbacks including diffusion,oxidation,or thermal expansion coefficient mismatch with chalcogenide PCMs during high-temperature phase transition,severely limiting the durability of chalcogenide PCM-based devices.In this paper,we propose,for the first time to our knowledge,the utilization of chalcogenide glass characterized by high thermal stability as a protective material for chalcogenide PCM.This approach addresses the durability challenge of current dynamic photonic devices based on chalcogenide PCM by virtue of their closely matched optical and thermal properties.Building upon this innovation,we introduce an all-chalcogenide dynamic tunable metasurface filter and comprehensively simulate and analyze its characteristics.This pioneering work paves the way for the design and practical implementation of optically dynamically tunable metasurface devices leveraging chalcogenide PCMs,ushering in new opportunities in the field.展开更多
The uncontrollable growth of Zn dendrites accompanied by side reactions severely impedes the industrialized process of zinc ion electrochemical energy storage devices.Herein,we propose a practical metalorganic complex...The uncontrollable growth of Zn dendrites accompanied by side reactions severely impedes the industrialized process of zinc ion electrochemical energy storage devices.Herein,we propose a practical metalorganic complex interface layer to manipulate the zinc ion flux and electric field intensity,enabling highly homogeneous zinc electrodeposition.The zinc-terephthalic acid complex(ZnPTA)with lower adsorption energy for zinc ion(-1.3 eV)builds a zincophilic interface favoring the ordered nucleation and growth of Zn.Moreover,the ZnPTA layer can serve as physical barrier to protect the newly deposited Zn from corrosion in the aqueous electrolyte.The modified Zn anode with the ZnPTA layer(ZnPTA@Zn)demonstrates excellent cycling stability more than 3000 h at 1 mA/cm^(2).Besides,the zinc-ion battery and zinc-ion hybrid capacitor using the ZnPTA@Zn electrode deliver outstanding cycle performance(up to 5500 cycles with high residual capacity ratio of 77.9%).This work provides a promising metal-organic complex interface design on enhancing the performance of Zn metal anode.展开更多
We report the search for neutrinoless double-beta decay of 136Xe from the PandaX-4T experiment with a 3.7-tonne natural xenon target.The data reconstruction and the background modeling are optimized in the MeV energy ...We report the search for neutrinoless double-beta decay of 136Xe from the PandaX-4T experiment with a 3.7-tonne natural xenon target.The data reconstruction and the background modeling are optimized in the MeV energy region.A blind analysis is performed with data from the commissioning run and the first science run.No significant excess of signal over the background is observed.A lower limit on the half-life of 136Xe neutrinoless double-beta decay is established to be 211024 yr at the 90%confidence level,with a 136Xe exposure of 44.6 kg yr.Our result represents the most stringent constraint from a natural xenon detector to date.展开更多
Metal–organic frameworks are linked by different central organic ligands and metal-ion coordination bonds to form periodic pore structures and rich pore volumes.Because of their structural advantages,metal–organic f...Metal–organic frameworks are linked by different central organic ligands and metal-ion coordination bonds to form periodic pore structures and rich pore volumes.Because of their structural advantages,metal–organic frameworks are considered to be one of the most promising candidates for new energy storage materials.To better utilize their advantages,metal–organic frameworks can be combined with electrospinning technology to effectively adjust the porosity and mechanical strength of composite materials.This paper summarizes the combination of the latest metal–organic frameworks and classical spinning technology,starting from the structural design of electrode materials,and applying them to supercapacitors,lithium-ion batteries,lithium–sulfur batteries,sodium-ion batteries,and potassium-ion batteries.Finally,the problems and challenges related to the preparation of metal–organic framework nanofibers are summarized,and future development trends are predicted.展开更多
We investigate numerically the pattern formation in 2-μm thulium-doped Mamyshev fiber oscillators, associated with the dissipative Faraday instability. The dispersion-managed fiber ring oscillator is designed with co...We investigate numerically the pattern formation in 2-μm thulium-doped Mamyshev fiber oscillators, associated with the dissipative Faraday instability. The dispersion-managed fiber ring oscillator is designed with commercial fibers, allowing the dynamics for a wide range of average dispersion regimes to be studied, from normal to nearzero cavity dispersion where the Benjamin–Feir instability remains inhibited. For the first time in the 2-μm spectral window, the formation of highly coherent periodic patterns is demonstrated numerically with rates up to ~100 GHz. In addition, irregular patterns are also investigated, revealing the generation of rogue waves via nonlinear collision processes. Our investigations have potential applications for the generation of multigigahertz frequency combs. They also shed new light on the dissipative Faraday instability mechanisms in the area of nonlinear optical cavity dynamics.展开更多
Transient thermal instability represents a significant challenge in generating soliton microcombs.Fast laser sweep can be an efficient method to mitigate thermal instability,but it requires an ultrahigh laser sweep ra...Transient thermal instability represents a significant challenge in generating soliton microcombs.Fast laser sweep can be an efficient method to mitigate thermal instability,but it requires an ultrahigh laser sweep rate for crystalline microresonators with fast thermal relaxation.Here,we engineer a laser sweep waveform to generate AlNon-sapphire soliton microcombs with an intermediate sweep speed(<30 GHz∕μs).Two laser sweep methods with backward plus forward tuning or two-step backward tuning added after the fast forward laser sweep were demonstrated to stabilize solitons.Reducing the soliton number is found to be useful to stabilize solitons in fast laser sweep.The effectiveness of the methods was numerically verified.Our measurements and simulations also reveal the impacts of different thermal relaxation processes occurring at quite different time scales on thermal instability.The requirement of the laser sweep protocols is discussed.展开更多
文摘The CdS/Bi_(2)S_(3) supported three-dimensional(3D)porous faveolate carbon structure(CdS/Bi_(2)S_(3)@C)composite photocatalyst was constructed.Bi_(2)S_(3) nanoparticles are regarded as photothermal agents and pyroelectric materials to absorb near infrared light(NIR)and convert it into heat.3D porous faveolate of carbon acts as incubator to reduce heat loss and optimize photothermal effects.There is a greater fluctuating temperature difference(ΔΤ)between photothermal effect of Bi_(2)S_(3) and cold photocatalytic system.This enhances the pyroelectric effect that Bi_(2)S_(3) undergoes spontaneous polarization and releases the surface charge.Therefore,the separation of electrons and holes in the CdS photocatalyst can be induced.The COMSOL simulation results show that,the higher pyroelectric potential producted by largerΔΤis more favorable to the photocatalytic process.The hydrogen evolution rate of CdS/Bi_(2)S_(3)@C photocatalyst can reach 5.88 mmol·g^(-1)·h^(-1) with excellent cycle stability.
基金supported by the Program of Marine Economy Development Special Fund under Department of Natural Resources of Guangdong Province(Grant No.GDNRC[2023]23)the National Natural Science Foundation of China(Grant Nos.62005098 and 61935013)+1 种基金the General Items of Guangzhou Science and Technology Plan Project(PhD Young Scientists and Technologists category)(Grant No.202201010320)the Fundamental Research Funds for the Central University(Grant No.11623415).
文摘Dynamically tunable metasurfaces employing chalcogenide phase-change materials(PCMs)such as Ge_(2)Sb_(2)Te_(5)alloys have garnered significant attention and research efforts.However,the utilization of chalcogenide PCMs in dynamic metasurface devices necessitates protection,owing to their susceptibility to volatilization and oxidation.Conventional protective layer materials such as Al_(2)O_(3),TiO_(2),and SiO_(2)present potential drawbacks including diffusion,oxidation,or thermal expansion coefficient mismatch with chalcogenide PCMs during high-temperature phase transition,severely limiting the durability of chalcogenide PCM-based devices.In this paper,we propose,for the first time to our knowledge,the utilization of chalcogenide glass characterized by high thermal stability as a protective material for chalcogenide PCM.This approach addresses the durability challenge of current dynamic photonic devices based on chalcogenide PCM by virtue of their closely matched optical and thermal properties.Building upon this innovation,we introduce an all-chalcogenide dynamic tunable metasurface filter and comprehensively simulate and analyze its characteristics.This pioneering work paves the way for the design and practical implementation of optically dynamically tunable metasurface devices leveraging chalcogenide PCMs,ushering in new opportunities in the field.
基金supported by the Fundamental Research Funds for the Central Universities,China。
文摘The uncontrollable growth of Zn dendrites accompanied by side reactions severely impedes the industrialized process of zinc ion electrochemical energy storage devices.Herein,we propose a practical metalorganic complex interface layer to manipulate the zinc ion flux and electric field intensity,enabling highly homogeneous zinc electrodeposition.The zinc-terephthalic acid complex(ZnPTA)with lower adsorption energy for zinc ion(-1.3 eV)builds a zincophilic interface favoring the ordered nucleation and growth of Zn.Moreover,the ZnPTA layer can serve as physical barrier to protect the newly deposited Zn from corrosion in the aqueous electrolyte.The modified Zn anode with the ZnPTA layer(ZnPTA@Zn)demonstrates excellent cycling stability more than 3000 h at 1 mA/cm^(2).Besides,the zinc-ion battery and zinc-ion hybrid capacitor using the ZnPTA@Zn electrode deliver outstanding cycle performance(up to 5500 cycles with high residual capacity ratio of 77.9%).This work provides a promising metal-organic complex interface design on enhancing the performance of Zn metal anode.
基金supported by the National Key R&D Program of China(2023YFA1606200 and 2023YFA1606202)the National Natural Science Foundation of China(12090060,12090062,and U23B2070)+6 种基金the Office of Science and Technology,Shanghai Municipal Government(21TQ1400218,22JC1410100,23JC1410200,and ZJ2023-ZD-003)the support by the Fundamental Research Funds for the Central Universitiesthe sponsorship from the Chinese Academy of Sciences Center for Excellence in Particle Physics(CCEPP)Hongwen Foundation in Hong KongNew Cornerstone Science FoundationTencent Foundation in ChinaYangyang Development Fund。
文摘We report the search for neutrinoless double-beta decay of 136Xe from the PandaX-4T experiment with a 3.7-tonne natural xenon target.The data reconstruction and the background modeling are optimized in the MeV energy region.A blind analysis is performed with data from the commissioning run and the first science run.No significant excess of signal over the background is observed.A lower limit on the half-life of 136Xe neutrinoless double-beta decay is established to be 211024 yr at the 90%confidence level,with a 136Xe exposure of 44.6 kg yr.Our result represents the most stringent constraint from a natural xenon detector to date.
基金Yao thanks the National Nature Science Foundation of China(21871066)China Scholarship Council(CSC,No.202006120429)S.Y.acknowledges Ms.Xin Luo for her support and encouragement during my study and life.
文摘Metal–organic frameworks are linked by different central organic ligands and metal-ion coordination bonds to form periodic pore structures and rich pore volumes.Because of their structural advantages,metal–organic frameworks are considered to be one of the most promising candidates for new energy storage materials.To better utilize their advantages,metal–organic frameworks can be combined with electrospinning technology to effectively adjust the porosity and mechanical strength of composite materials.This paper summarizes the combination of the latest metal–organic frameworks and classical spinning technology,starting from the structural design of electrode materials,and applying them to supercapacitors,lithium-ion batteries,lithium–sulfur batteries,sodium-ion batteries,and potassium-ion batteries.Finally,the problems and challenges related to the preparation of metal–organic framework nanofibers are summarized,and future development trends are predicted.
基金National Natural Science Foundation of China(51527901,61575106)
文摘We investigate numerically the pattern formation in 2-μm thulium-doped Mamyshev fiber oscillators, associated with the dissipative Faraday instability. The dispersion-managed fiber ring oscillator is designed with commercial fibers, allowing the dynamics for a wide range of average dispersion regimes to be studied, from normal to nearzero cavity dispersion where the Benjamin–Feir instability remains inhibited. For the first time in the 2-μm spectral window, the formation of highly coherent periodic patterns is demonstrated numerically with rates up to ~100 GHz. In addition, irregular patterns are also investigated, revealing the generation of rogue waves via nonlinear collision processes. Our investigations have potential applications for the generation of multigigahertz frequency combs. They also shed new light on the dissipative Faraday instability mechanisms in the area of nonlinear optical cavity dynamics.
基金National Natural Science Foundation of China(62022080,62175127,62250071)National Key Research and Development Program of China(2021YFB2801200)+3 种基金Tsinghua Initiative Scientific Research Program(20211080080,20221080069)Youth Innovation Promotion Association of the Chinese Academy of Sciences(2023123)SJTU-Pinghu Institute of Intelligent OptoelectronicsTsinghua-Toyota Joint Research Fund。
文摘Transient thermal instability represents a significant challenge in generating soliton microcombs.Fast laser sweep can be an efficient method to mitigate thermal instability,but it requires an ultrahigh laser sweep rate for crystalline microresonators with fast thermal relaxation.Here,we engineer a laser sweep waveform to generate AlNon-sapphire soliton microcombs with an intermediate sweep speed(<30 GHz∕μs).Two laser sweep methods with backward plus forward tuning or two-step backward tuning added after the fast forward laser sweep were demonstrated to stabilize solitons.Reducing the soliton number is found to be useful to stabilize solitons in fast laser sweep.The effectiveness of the methods was numerically verified.Our measurements and simulations also reveal the impacts of different thermal relaxation processes occurring at quite different time scales on thermal instability.The requirement of the laser sweep protocols is discussed.
