Microwaves are often used in communication engineering,including in microwave relays as well as mul-tichannel,mobile,and satellite communications.To meet the demand for a“small,light,thin,and precise”modern electron...Microwaves are often used in communication engineering,including in microwave relays as well as mul-tichannel,mobile,and satellite communications.To meet the demand for a“small,light,thin,and precise”modern electronic machine,developing highly tunable microwave materials to manufacture miniaturized microwave devices has become a top priority.Ferroelectric materials are excellent microwave materi-als,showing outstanding dielectric properties and tunability.Introducing low dielectric loss oxides in the construction of vertical self-assembly nanocomposites(VSNs)effectively improves their tunability and reduces dielectric loss.However,the optimal doping content of simple VSN films limits further improve-ment of tunability.Herein,we propose a strategy-gradient VSN to achieve combined improvement in tunability and dielectric constant by designing a sputtering and pulsed laser co-deposition.The resulting VSN composite film has a dielectric constant of 428.08,a dielectric loss of 0.0212,and a tunability of 78.69%.Our results contribute to the development of filters and have broad application prospects in the microwave industry.展开更多
Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications,which are becoming increasingly important for power electronics nowadays.Among them,AgNbO_(3) based lead-free cer...Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications,which are becoming increasingly important for power electronics nowadays.Among them,AgNbO_(3) based lead-free ceramics have attracted intensive interest as one of promising environmental-friendly candidates.However,most of the AgNbO_(3) based ceramics suffers from low dielectric breakdown strength(Eb).The limitation of low Eb is broken to some extent in this work.Here,AgNbO_(3) epitaxial films were fabricated by pulsed laser deposition,which possess high Eb of 624 kV/cm.The(001)AgNbO_(3) epitaxial film reveals typical antiferroelectric hysteresis loops when the applied electric fields are over 300 kV/cm.A recoverable energy density of 5.8 J/cm^(3) and an energy efficiency of 55.8%are obtained at 600 kV/cm,which demonstrates the great promise of the AgNbO_(3) film for energy storage applications.展开更多
基金supported by the NSFC(No.11374086)and the NSF of Hebei Province(No.E2014201188)the Post-graduate Innovation Fund Project of Hebei University(No.HBU2022bs009)the Project of Distinguished Young of Hebei Province(No.A2018201231).
文摘Microwaves are often used in communication engineering,including in microwave relays as well as mul-tichannel,mobile,and satellite communications.To meet the demand for a“small,light,thin,and precise”modern electronic machine,developing highly tunable microwave materials to manufacture miniaturized microwave devices has become a top priority.Ferroelectric materials are excellent microwave materi-als,showing outstanding dielectric properties and tunability.Introducing low dielectric loss oxides in the construction of vertical self-assembly nanocomposites(VSNs)effectively improves their tunability and reduces dielectric loss.However,the optimal doping content of simple VSN films limits further improve-ment of tunability.Herein,we propose a strategy-gradient VSN to achieve combined improvement in tunability and dielectric constant by designing a sputtering and pulsed laser co-deposition.The resulting VSN composite film has a dielectric constant of 428.08,a dielectric loss of 0.0212,and a tunability of 78.69%.Our results contribute to the development of filters and have broad application prospects in the microwave industry.
基金supported by the National Natural Science Foundation of China(No.51802068 and No.52073144)Advanced Talents Incubation Program of the Hebei University,China(No.801260201180)+2 种基金the Natural Science Foundation of Jiangsu Province,China(No.BK20201301)the State Key Laboratory of New Ceramic and Fine Processing Tsinghua University(No.KF202005)the Basic Scientific Research Program of National Institute of Metrology(No.AKY1949).
文摘Antiferroelectric materials with double hysteresis loops are attractive for energy storage applications,which are becoming increasingly important for power electronics nowadays.Among them,AgNbO_(3) based lead-free ceramics have attracted intensive interest as one of promising environmental-friendly candidates.However,most of the AgNbO_(3) based ceramics suffers from low dielectric breakdown strength(Eb).The limitation of low Eb is broken to some extent in this work.Here,AgNbO_(3) epitaxial films were fabricated by pulsed laser deposition,which possess high Eb of 624 kV/cm.The(001)AgNbO_(3) epitaxial film reveals typical antiferroelectric hysteresis loops when the applied electric fields are over 300 kV/cm.A recoverable energy density of 5.8 J/cm^(3) and an energy efficiency of 55.8%are obtained at 600 kV/cm,which demonstrates the great promise of the AgNbO_(3) film for energy storage applications.
