The low surface energy and hierarchical micro/nanostructures endow microwave-absorbing materials with superhydrophobicity to avoid the adverse effects of high-humidity environments on their perfor-mance and structure....The low surface energy and hierarchical micro/nanostructures endow microwave-absorbing materials with superhydrophobicity to avoid the adverse effects of high-humidity environments on their perfor-mance and structure.Notably,fluoridizing engineering can meet these requirements by regulating the material morphology,defect distribution,surface polarization and forming hydrophobic structures.In this study,we designed a combined oxidation-fluoridizing method to obtain an electromagnetic wave ab-sorbing and superhydrophobic material,namely,fluoridizing graphene@copper(F-GE@Cu)hybrids with multi-interfacial heterostructures.This strategy involved the oxidation of graphene-wrapped Cu nanopar-ticles(GE@Cu)prepared by the thermal decomposition of cupric tartrate to GE@Cu_(x) O(x=1 and 2)and further fluorination by PTFE pyrolysis to obtain F-GE@Cu with a yolk-shell structure.Multi-interfacial heterostructures were achieved using precise modulation of the Cu particle,carbon-cladding layer,and fluoridizing products such as CuF_(2) and fluorinated graphene(FGE),this resulted in improved interfacial polarization and impedance matching to achieve satisfactory broadband and electromagnetic wave loss performance.Consequently,the as-prepared fluorinated graphene@copper fluoride(FGE@CuF_(2))exhibited high performance for electromagnetic wave(EMW)absorption with an intense reflection loss(RLmin)of−53.0 dB and a broad effective bandwidth(EAB)of 8.9 GHz(9.1-18.0 GHz).Additionally,the FGE cladding conferred the hybrids with excellent superhydrophobic properties(WAC=154.0°),allowing it to tolerate diverse and harsh water-containing environments,providing the microwave-absorbing coatings with a universal waterproofing capability.This study presents a new strategy for preparing multifunctional elec-tromagnetic wave-absorbing materials.展开更多
The rapid development of miniaturized and high-power electronics urgently demands multifunctional materials that simultaneously mitigate thermal shock and electromagnetic interference(EMI).While phase change materials...The rapid development of miniaturized and high-power electronics urgently demands multifunctional materials that simultaneously mitigate thermal shock and electromagnetic interference(EMI).While phase change materials(PCMs)offer thermal buffering capabilities,their limited thermal conductivity and inability to address EMI restrict applications in integrated electronic systems.Herein,we develop multi-interfacial engineered composite PCMs(PW-MXene/CNFs@MoS_(2))that synergistically integrate thermal management and electromagnetic wave(EMW)absorption.Through hierarchical assembly of 2D MXene and MoS_(2) nanosheets on a 3D carbon nanofiber(CNF)network,composite PCMs achieve synergistic dual functionality.The architecture establishes an efficient phonon conductive framework for rapid thermal dissipation,while maintaining remarkable heat storage capacity of 121.8 J/g.Additionally,polarization-enhanced heterointerfaces enable excellent EMW absorption(−64.1 dB reflection loss across 4.28 GHz bandwidth below 2.1 mm).The composite PCMs also exhibit outstanding cyclic stability,retaining 97% of their phase change enthalpy after 300 thermal cycles,while maintaining superior leakage resistance under combined thermal and mechanical stresses.Practical validation reveals its dual functionality:a 6.4℃ thermal buffer under 1200 W/m^(2) thermal shock and effective Bluetooth signal shielding.This work provides an innovative solution for the synergistic management of thermal shock and electromagnetic interference issues,showing viable potential for applications in advanced electronic systems.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51573149)。
文摘The low surface energy and hierarchical micro/nanostructures endow microwave-absorbing materials with superhydrophobicity to avoid the adverse effects of high-humidity environments on their perfor-mance and structure.Notably,fluoridizing engineering can meet these requirements by regulating the material morphology,defect distribution,surface polarization and forming hydrophobic structures.In this study,we designed a combined oxidation-fluoridizing method to obtain an electromagnetic wave ab-sorbing and superhydrophobic material,namely,fluoridizing graphene@copper(F-GE@Cu)hybrids with multi-interfacial heterostructures.This strategy involved the oxidation of graphene-wrapped Cu nanopar-ticles(GE@Cu)prepared by the thermal decomposition of cupric tartrate to GE@Cu_(x) O(x=1 and 2)and further fluorination by PTFE pyrolysis to obtain F-GE@Cu with a yolk-shell structure.Multi-interfacial heterostructures were achieved using precise modulation of the Cu particle,carbon-cladding layer,and fluoridizing products such as CuF_(2) and fluorinated graphene(FGE),this resulted in improved interfacial polarization and impedance matching to achieve satisfactory broadband and electromagnetic wave loss performance.Consequently,the as-prepared fluorinated graphene@copper fluoride(FGE@CuF_(2))exhibited high performance for electromagnetic wave(EMW)absorption with an intense reflection loss(RLmin)of−53.0 dB and a broad effective bandwidth(EAB)of 8.9 GHz(9.1-18.0 GHz).Additionally,the FGE cladding conferred the hybrids with excellent superhydrophobic properties(WAC=154.0°),allowing it to tolerate diverse and harsh water-containing environments,providing the microwave-absorbing coatings with a universal waterproofing capability.This study presents a new strategy for preparing multifunctional elec-tromagnetic wave-absorbing materials.
基金financially supported by the National Natural Science Foundation of China(Nos.U24A20532,51902025)Research Funds of Institute of Zhejiang University-Quzhou(No.IZQ2023RCZX032).
文摘The rapid development of miniaturized and high-power electronics urgently demands multifunctional materials that simultaneously mitigate thermal shock and electromagnetic interference(EMI).While phase change materials(PCMs)offer thermal buffering capabilities,their limited thermal conductivity and inability to address EMI restrict applications in integrated electronic systems.Herein,we develop multi-interfacial engineered composite PCMs(PW-MXene/CNFs@MoS_(2))that synergistically integrate thermal management and electromagnetic wave(EMW)absorption.Through hierarchical assembly of 2D MXene and MoS_(2) nanosheets on a 3D carbon nanofiber(CNF)network,composite PCMs achieve synergistic dual functionality.The architecture establishes an efficient phonon conductive framework for rapid thermal dissipation,while maintaining remarkable heat storage capacity of 121.8 J/g.Additionally,polarization-enhanced heterointerfaces enable excellent EMW absorption(−64.1 dB reflection loss across 4.28 GHz bandwidth below 2.1 mm).The composite PCMs also exhibit outstanding cyclic stability,retaining 97% of their phase change enthalpy after 300 thermal cycles,while maintaining superior leakage resistance under combined thermal and mechanical stresses.Practical validation reveals its dual functionality:a 6.4℃ thermal buffer under 1200 W/m^(2) thermal shock and effective Bluetooth signal shielding.This work provides an innovative solution for the synergistic management of thermal shock and electromagnetic interference issues,showing viable potential for applications in advanced electronic systems.
