We construct the Hall-bar device with the size of several hundred nanometers based on the HZO/Co multiferroic heterojunction. A remarkable voltage-controlled magnetism is observed in the device that possesses both fer...We construct the Hall-bar device with the size of several hundred nanometers based on the HZO/Co multiferroic heterojunction. A remarkable voltage-controlled magnetism is observed in the device that possesses both ferroelectric property and perpendicular magnetic anisotropy(PMA). The nucleation field and coercivity can be modulated by voltage pulse while saturation field keeps stable. The non-volatile and reversible voltage-controlled magnetism is ascribable to interfacial charges caused by ferroelectric polarization. Meanwhile, the effective anisotropy energy density(Ku) can also be controlled by voltage pulse, a decrease of 83% and increase of 28% in Kuare realized under-3-V and 3-V pulses,respectively. Because the energy barrier is directly proportional to Ku under a given volume, a decreased or enhanced energy barrier can be controlled by voltage pulse. Thus, it is an effective method to realize low-power and high-stability magneto-resistive random-access memory(MRAM).展开更多
Although Ti3 C2 MXene sheets have attracted extensive attention in lithium-ion storage techniques,their restacking makes against and even hinders the Li ions diffusion within them,thereby decreasing the capacity as we...Although Ti3 C2 MXene sheets have attracted extensive attention in lithium-ion storage techniques,their restacking makes against and even hinders the Li ions diffusion within them,thereby decreasing the capacity as well as rate performance of conventional MXene anode.Here,for the first time,we roll up the Ti3 C2 Tx sheets into scrolls with unclosed topological structure and the interlayer galleries to alleviate the restacking problem.Thus,Ti3 C2 Tx scrolls as anode materials in lithium-ion batteries(LIBs)have higher capacity and better rate performance than Ti3 C2 Tx sheets.On the bases of these,high-capacity silicon nanoparticles are added during the rolling process to in-situ produce Ti3 C2 Tx/Si composite scrolls.The addition of 10%silicon nanoparticles shows the best overall improvement among capacity,rate capability and cyclic stability for Ti3 C2 Tx scrolls.展开更多
The Fe3O4@SiO2 composite nanoparticles were obtained from as-synthesized magnetite (Fe3O4) nanoparticles through the modified St?ber method. Then, the Fe3O4 nanoparticles and Fe3O4@SiO2 composite nanoparticles were ch...The Fe3O4@SiO2 composite nanoparticles were obtained from as-synthesized magnetite (Fe3O4) nanoparticles through the modified St?ber method. Then, the Fe3O4 nanoparticles and Fe3O4@SiO2 composite nanoparticles were characterized by means of X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). Recently, the studies focus on how to improve the dispersion of composite particle and achieve good magnetic performance. Hence effects of the volume ratio of tetraethyl orthosilicate (TEOS) and magnetite colloid on the structural, morphological and magnetic properties of the composite nanoparticles were systematically investi-gated. The results revealed that the Fe3O4@SiO2 had better thermal stability and dispersion than the magnetite nanoparticles. Furthermore, the particle size and magnetic property of the Fe3O4@SiO2 composite nanoparticles can be adjusted by changing the volume ratio of TEOS and magnetite colloid.展开更多
The rapid development of next-generation flexible electronics stimulates the growing demand for flexible and wearable power sources with high energy density.Li metal capacitor(LMC),combining with a Li metal anode and ...The rapid development of next-generation flexible electronics stimulates the growing demand for flexible and wearable power sources with high energy density.Li metal capacitor(LMC),combining with a Li metal anode and an activated carbon cathode,exhibits extremely high energy density and high power density due to the unique energy storage mechanism,thus showing great potential for powering wearable electronic devices.Herein,a flexible LMC based on an in situ prepared PETEA-based gel polymer electrolyte(GPE)was reported for the first time.Owing to the high ionic conductivity of PETEA-based GPE(5.75×10^(−3)S/cm at 20℃),the assembled flexible LMC delivers a high capacitance of 210 F/g at 0.1 A/g within the voltage range from 1.5 V to 4.3 V vs.Li/Li^(+),a high energy density of 474 Wh/kg at 0.1 A/g and a high power density of 29 kW/kg at 10 A/g.More importantly,PETEA-based GPE endows the LMC with excellent flexibility and safety,which could work normally under abuse tests,such as bending,nail penetration and cutting.The in situ prepared PETEA-based GPE simplifies the fabrication process,avoids the risk of leakage and inhibits the growth of Li dendrite,making LMC a promising flexible energy storage device for the flexible electronic field.展开更多
基金supported by Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA18000000)the Fund from the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Grant No. 2015097)Guangzhou City Research and Development Program in Key Fields (Grant No. 202103020001)。
文摘We construct the Hall-bar device with the size of several hundred nanometers based on the HZO/Co multiferroic heterojunction. A remarkable voltage-controlled magnetism is observed in the device that possesses both ferroelectric property and perpendicular magnetic anisotropy(PMA). The nucleation field and coercivity can be modulated by voltage pulse while saturation field keeps stable. The non-volatile and reversible voltage-controlled magnetism is ascribable to interfacial charges caused by ferroelectric polarization. Meanwhile, the effective anisotropy energy density(Ku) can also be controlled by voltage pulse, a decrease of 83% and increase of 28% in Kuare realized under-3-V and 3-V pulses,respectively. Because the energy barrier is directly proportional to Ku under a given volume, a decreased or enhanced energy barrier can be controlled by voltage pulse. Thus, it is an effective method to realize low-power and high-stability magneto-resistive random-access memory(MRAM).
基金supported by the National Natural Science Foundation of China(Grant No.21573265,21673263,and 21805291)One-Three-Five Strategic Planning of Chinese Academy of Sciences and the DNL Cooperation Fund,CAS(DNL180307)。
文摘Although Ti3 C2 MXene sheets have attracted extensive attention in lithium-ion storage techniques,their restacking makes against and even hinders the Li ions diffusion within them,thereby decreasing the capacity as well as rate performance of conventional MXene anode.Here,for the first time,we roll up the Ti3 C2 Tx sheets into scrolls with unclosed topological structure and the interlayer galleries to alleviate the restacking problem.Thus,Ti3 C2 Tx scrolls as anode materials in lithium-ion batteries(LIBs)have higher capacity and better rate performance than Ti3 C2 Tx sheets.On the bases of these,high-capacity silicon nanoparticles are added during the rolling process to in-situ produce Ti3 C2 Tx/Si composite scrolls.The addition of 10%silicon nanoparticles shows the best overall improvement among capacity,rate capability and cyclic stability for Ti3 C2 Tx scrolls.
文摘The Fe3O4@SiO2 composite nanoparticles were obtained from as-synthesized magnetite (Fe3O4) nanoparticles through the modified St?ber method. Then, the Fe3O4 nanoparticles and Fe3O4@SiO2 composite nanoparticles were characterized by means of X-ray diffraction (XRD), Raman spectra, scanning electron microscope (SEM) and vibrating sample magnetometer (VSM). Recently, the studies focus on how to improve the dispersion of composite particle and achieve good magnetic performance. Hence effects of the volume ratio of tetraethyl orthosilicate (TEOS) and magnetite colloid on the structural, morphological and magnetic properties of the composite nanoparticles were systematically investi-gated. The results revealed that the Fe3O4@SiO2 had better thermal stability and dispersion than the magnetite nanoparticles. Furthermore, the particle size and magnetic property of the Fe3O4@SiO2 composite nanoparticles can be adjusted by changing the volume ratio of TEOS and magnetite colloid.
基金the financial support from the Natural Science Foundation of Gansu(No.20JR10RA611)the Fundamental Research Funds for the Central Universities(Nos.Lzujbky-2017-178 and lzujbky-2017-181).
文摘The rapid development of next-generation flexible electronics stimulates the growing demand for flexible and wearable power sources with high energy density.Li metal capacitor(LMC),combining with a Li metal anode and an activated carbon cathode,exhibits extremely high energy density and high power density due to the unique energy storage mechanism,thus showing great potential for powering wearable electronic devices.Herein,a flexible LMC based on an in situ prepared PETEA-based gel polymer electrolyte(GPE)was reported for the first time.Owing to the high ionic conductivity of PETEA-based GPE(5.75×10^(−3)S/cm at 20℃),the assembled flexible LMC delivers a high capacitance of 210 F/g at 0.1 A/g within the voltage range from 1.5 V to 4.3 V vs.Li/Li^(+),a high energy density of 474 Wh/kg at 0.1 A/g and a high power density of 29 kW/kg at 10 A/g.More importantly,PETEA-based GPE endows the LMC with excellent flexibility and safety,which could work normally under abuse tests,such as bending,nail penetration and cutting.The in situ prepared PETEA-based GPE simplifies the fabrication process,avoids the risk of leakage and inhibits the growth of Li dendrite,making LMC a promising flexible energy storage device for the flexible electronic field.