The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engin...The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric genes.Electron migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent dipoles.Herein,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent dipoles.By virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 mm.The mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).展开更多
The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various field...The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.展开更多
Homogeneous heterogeneous(heterophase)interfaces regulated with low energy barriers have a fast response to applied electric fields and could provide a unique interfacial polarization,which facilitate the transport of...Homogeneous heterogeneous(heterophase)interfaces regulated with low energy barriers have a fast response to applied electric fields and could provide a unique interfacial polarization,which facilitate the transport of electrons across the substrate.Such regulation on the interfaces is effective in modulating electromagnetic wave absorbing materials.Herein,we construct NbS_(2)–NiS_(2)heterostructures with NiS_(2)nanoparticles uniformly grown in NbS_(2)hollow nanospheres,and such particular structure enhances the interfacial polarization.The strong electron transfer at the interface promotes electron transport throughout the material,which results in less scattering,promotes conduct ion loss and dielectric polarization relaxation,improves dielectric loss,and results in a good impedance matching of the material.Consequently,the absorbing band may be successful tuned.By regulating the amount of NiS_(2),the heterogeneous interface is finely alternated so that the overall wave-absorbing performance is shifted to lower frequencies.With a NiS_(2)content of 15 wt%and an absorber thickness of 1.84 mm,the minimum reflection loss at 14.56 GHz is53.1 dB,and the effective absorption bandwidth is 5.04 GHz;more importantly,the minimum reflection loss in different bands is20 dB,and the microwave energy absorption rate reaches 99%when the thickness is about 1.5–4.5 mm.This work demonstrates the construction of homogeneous heterostructures is effective in improving the electromagnetic absorption properties,providing guideline for the synthesis of highly efficient electromagnetic absorbing materials.展开更多
As electromagnetic technology advances and demand for electronic devices grows,concerns about electromagnetic pollution intensify.This has spurred focused research on innovative electromagnetic absorbers,particularly ...As electromagnetic technology advances and demand for electronic devices grows,concerns about electromagnetic pollution intensify.This has spurred focused research on innovative electromagnetic absorbers,particularly chalcogenides,noted for their superior absorption capabilities.In this study,we successfully synthesize 3R–TaS_(2)nanosheets using a straightforward calcination method for the first time.These nanosheets exhibit significant absorption capabilities in both the C-band(4–8 GHz)and Ku-band(12–18 GHz)frequency ranges.By optimizing the calcination process,the complex permittivity of TaS_(2)is enhanced,specifically for those synthesized at 1000℃for 24 h.The nanosheets possess dual-band absorption properties,with a notable minimum reflection loss(RLmin)of41.4 dB in the C-band,and an average absorption intensity exceeding 10 dB in C-and Ku-bands,in the absorbers with a thickness of 5.6 mm.Additionally,the 3R–TaS_(2)nanosheets are demonstrated to have an effective absorption bandwidth of 5.04 GHz(3.84–8.88 GHz)in the absorbers with thicknesses of 3.5–5.5 mm.The results highlight the multiple reflection effects in 3R–TaS_(2)as caused by their stacked structures,which could be promising low-frequency absorbers.展开更多
With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shieldin...With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential role.Meanwhile,the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding applications.Hitherto,a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been developed.In this review,we not only introduce the recent development of flexible EMI shielding materials,but also elaborate the EMI shielding mechanisms and the index for"green EMI shielding"performance.In addition,the construction strategies for sophisticated multifunctionalities of flexible shielding materials are summarized.Finally,we propose several possible research directions for flexible EMI shielding materials in near future,which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials.展开更多
Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene o...Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first time.Remarkably,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption performance.The results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.展开更多
Two-dimensional black phosphorus(2D BP),well known as phosphorene,has triggered tremendous attention since the first discovery in 2014.The unique puckered monolayer structure endows 2D BP intriguing properties,which f...Two-dimensional black phosphorus(2D BP),well known as phosphorene,has triggered tremendous attention since the first discovery in 2014.The unique puckered monolayer structure endows 2D BP intriguing properties,which facilitate its potential applications in various fields,such as catalyst,energy storage,sensor,etc.Owing to the large surface area,good electric conductivity,and high theoretical specific capacity,2D BP has been widely studied as electrode materials and significantly enhanced the performance of energy storage devices.With the rapid development of energy storage devices based on 2D BP,a timely review on this topic is in demand to further extend the application of 2D BP in energy storage.In this review,recent advances in experimental and theoretical development of 2D BP are presented along with its structures,properties,and synthetic methods.Particularly,their emerging applications in electrochemical energy storage,including Li−/K−/Mg−/Na-ion,Li–S batteries,and supercapacitors,are systematically summarized with milestones as well as the challenges.Benefited from the fast-growing dynamic investigation of 2D BP,some possible improvements and constructive perspectives are provided to guide the design of 2D BP-based energy storage devices with high performance.展开更多
基金Financial support from the National Natural Science Foundation of China(52372289,52102368,52231007,12327804,T2321003,22088101,22178037 and U22A20424)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020A1515110905)+1 种基金Guangdong Special Fund for key Areas(20237DZX3042)Shenzhen Stable Support Project,Liaoning Revitalization Talents Program(XLYC2002114)are highly appreciated.
文摘The synthesis of carbon supporter/nanoscale high-entropy alloys(HEAs)electromagnetic response composites by carbothermal shock method has been identified as an advanced strategy for the collaborative competition engineering of conductive/dielectric genes.Electron migration modes within HEAs as manipulated by the electronegativity,valence electron configurations and molar proportions of constituent elements determine the steady state and efficiency of equivalent dipoles.Herein,enlightened by skin-like effect,a reformative carbothermal shock method using carbonized cellulose paper(CCP)as carbon supporter is used to preserve the oxygencontaining functional groups(O·)of carbonized cellulose fibers(CCF).Nucleation of HEAs and construction of emblematic shell-core CCF/HEAs heterointerfaces are inextricably linked to carbon metabolism induced by O·.Meanwhile,the electron migration mode of switchable electronrich sites promotes the orientation polarization of anisotropic equivalent dipoles.By virtue of the reinforcement strategy,CCP/HEAs composite prepared by 35%molar ratio of Mn element(CCP/HEAs-Mn_(2.15))achieves efficient electromagnetic wave(EMW)absorption of−51.35 dB at an ultra-thin thickness of 1.03 mm.The mechanisms of the resulting dielectric properties of HEAs-based EMW absorbing materials are elucidated by combining theoretical calculations with experimental characterizations,which provide theoretical bases and feasible strategies for the simulation and practical application of electromagnetic functional devices(e.g.,ultra-wideband bandpass filter).
基金This work was supported by the National Natural Science Foundation of China(52372289,52102368,52072192 and 51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905).
文摘The laminated transition metal disulfides(TMDs),which are well known as typical two-dimensional(2D)semiconductive materials,possess a unique layered structure,leading to their wide-spread applications in various fields,such as catalysis,energy storage,sensing,etc.In recent years,a lot of research work on TMDs based functional materials in the fields of electromagnetic wave absorption(EMA)has been carried out.Therefore,it is of great significance to elaborate the influence of TMDs on EMA in time to speed up the application.In this review,recent advances in the development of electromagnetic wave(EMW)absorbers based on TMDs,ranging from the VIB group to the VB group are summarized.Their compositions,microstructures,electronic properties,and synthesis methods are presented in detail.Particularly,the modulation of structure engineering from the aspects of heterostructures,defects,morphologies and phases are systematically summarized,focusing on optimizing impedance matching and increasing dielectric and magnetic losses in the EMA materials with tunable EMW absorption performance.Milestones as well as the challenges are also identified to guide the design of new TMDs based dielectric EMA materials with high performance.
基金supported by the National Natural Science Foundation of China(52372289,52102368,52072192 and 51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020A1515110905)+1 种基金Guangdong Special Fund for key Areas(20237DZX3042)Shenzhen Stable Support Project and the Fundamental Research Fund of Heilongjiang Provincial University(145309101)。
文摘Homogeneous heterogeneous(heterophase)interfaces regulated with low energy barriers have a fast response to applied electric fields and could provide a unique interfacial polarization,which facilitate the transport of electrons across the substrate.Such regulation on the interfaces is effective in modulating electromagnetic wave absorbing materials.Herein,we construct NbS_(2)–NiS_(2)heterostructures with NiS_(2)nanoparticles uniformly grown in NbS_(2)hollow nanospheres,and such particular structure enhances the interfacial polarization.The strong electron transfer at the interface promotes electron transport throughout the material,which results in less scattering,promotes conduct ion loss and dielectric polarization relaxation,improves dielectric loss,and results in a good impedance matching of the material.Consequently,the absorbing band may be successful tuned.By regulating the amount of NiS_(2),the heterogeneous interface is finely alternated so that the overall wave-absorbing performance is shifted to lower frequencies.With a NiS_(2)content of 15 wt%and an absorber thickness of 1.84 mm,the minimum reflection loss at 14.56 GHz is53.1 dB,and the effective absorption bandwidth is 5.04 GHz;more importantly,the minimum reflection loss in different bands is20 dB,and the microwave energy absorption rate reaches 99%when the thickness is about 1.5–4.5 mm.This work demonstrates the construction of homogeneous heterostructures is effective in improving the electromagnetic absorption properties,providing guideline for the synthesis of highly efficient electromagnetic absorbing materials.
基金supported by the National Natural Science Foundation of China(52372289,52102368,52072192 and 51977009)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020A1515110905)+1 种基金Guangdong Special Fund for key Areas(20237DZX3042)Shenzhen Stable Support Project.
文摘As electromagnetic technology advances and demand for electronic devices grows,concerns about electromagnetic pollution intensify.This has spurred focused research on innovative electromagnetic absorbers,particularly chalcogenides,noted for their superior absorption capabilities.In this study,we successfully synthesize 3R–TaS_(2)nanosheets using a straightforward calcination method for the first time.These nanosheets exhibit significant absorption capabilities in both the C-band(4–8 GHz)and Ku-band(12–18 GHz)frequency ranges.By optimizing the calcination process,the complex permittivity of TaS_(2)is enhanced,specifically for those synthesized at 1000℃for 24 h.The nanosheets possess dual-band absorption properties,with a notable minimum reflection loss(RLmin)of41.4 dB in the C-band,and an average absorption intensity exceeding 10 dB in C-and Ku-bands,in the absorbers with a thickness of 5.6 mm.Additionally,the 3R–TaS_(2)nanosheets are demonstrated to have an effective absorption bandwidth of 5.04 GHz(3.84–8.88 GHz)in the absorbers with thicknesses of 3.5–5.5 mm.The results highlight the multiple reflection effects in 3R–TaS_(2)as caused by their stacked structures,which could be promising low-frequency absorbers.
基金This work was financially supported by the National Natural Science Foundation of China(51725101,11727807,51672050,61790581,52102368,52101213)the Ministry of Science and Technology of China(973 Project No.2018YFA0209102)+6 种基金University Development Fund(UDF0100152)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(Grant No.2017ZT07C291)Shenzhen Science and Technology Program(Grant No.KQTD20170810141424366)China Postdoctoral Science Foundation(Grant No.2020M680085)Regional Joint Fund for Basic Research and Applied Basic Research of Guangdong Province(No.2020SA001515110905)Science and Technology Department of Jiangsu Province of China(Grant No.BK20210261)Open access funding provided by Shanghai Jiao Tong University
文摘With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential role.Meanwhile,the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding applications.Hitherto,a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been developed.In this review,we not only introduce the recent development of flexible EMI shielding materials,but also elaborate the EMI shielding mechanisms and the index for"green EMI shielding"performance.In addition,the construction strategies for sophisticated multifunctionalities of flexible shielding materials are summarized.Finally,we propose several possible research directions for flexible EMI shielding materials in near future,which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials.
基金financially supported by the National Natural Science Foundation of China (Nos. 51272110, 51772160, and 51771123)the Shenzhen Peacock Innovation Project (No. KQJSCX20170327151307811)+1 种基金the support of China Scholarship Council (No. 201506100018)the START project of Japan Science and Technology Agency (JST)
文摘Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic properties.In this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first time.Remarkably,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption performance.The results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.
基金This work was supported by the National Key R&D Program of China(2019YFB2204500).
文摘Two-dimensional black phosphorus(2D BP),well known as phosphorene,has triggered tremendous attention since the first discovery in 2014.The unique puckered monolayer structure endows 2D BP intriguing properties,which facilitate its potential applications in various fields,such as catalyst,energy storage,sensor,etc.Owing to the large surface area,good electric conductivity,and high theoretical specific capacity,2D BP has been widely studied as electrode materials and significantly enhanced the performance of energy storage devices.With the rapid development of energy storage devices based on 2D BP,a timely review on this topic is in demand to further extend the application of 2D BP in energy storage.In this review,recent advances in experimental and theoretical development of 2D BP are presented along with its structures,properties,and synthetic methods.Particularly,their emerging applications in electrochemical energy storage,including Li−/K−/Mg−/Na-ion,Li–S batteries,and supercapacitors,are systematically summarized with milestones as well as the challenges.Benefited from the fast-growing dynamic investigation of 2D BP,some possible improvements and constructive perspectives are provided to guide the design of 2D BP-based energy storage devices with high performance.
