本文通过气相硒化成功制备了CoSe2/FeSe2@NC异质结复合材料,将未包覆碳层的CoSe2/FeSe2作为对比。当应用于锂离子电池负极材料,CoSe2/FeSe2@NC异质结负极材料相比于CoSe2/FeSe2表现出更为优异的电化学性能。在大电流密度2A g-1循环400圈...本文通过气相硒化成功制备了CoSe2/FeSe2@NC异质结复合材料,将未包覆碳层的CoSe2/FeSe2作为对比。当应用于锂离子电池负极材料,CoSe2/FeSe2@NC异质结负极材料相比于CoSe2/FeSe2表现出更为优异的电化学性能。在大电流密度2A g-1循环400圈,仍然保持高可逆容量463.4 mAh g-1。倍率性能测试中在5 A g-1大电流密度下具有420.9 mAh g-1的高放电比容量。CoSe2/FeSe2@NC优异的电化学性能得利于合理的异质结构设计和外部包覆碳层的协同作用,在提高复合材料循环过程中稳定性的同时加快了材料电子-离子传输动力学。展开更多
Wettability and the light-trapping effect of FeSe2 particles with a micro-nano hierarchical structure have been inves- tigated. Particles are synthesized by an improved solvothermal method, wherein hexadecyl trimetbyl...Wettability and the light-trapping effect of FeSe2 particles with a micro-nano hierarchical structure have been inves- tigated. Particles are synthesized by an improved solvothermal method, wherein hexadecyl trimetbyl ammonium bromide （CTAB） is employed as a surfactant. After modifying the particles with heptadecafluorodecyltrimethoxy-silane （HTMS）, we find that the water contact angle （WCA） of the FeSe2 particles increases by 6.1~ and the water sliding angle （WSA） decreases by 2.5~ respectively, and the diffuse reflectivity decreases 29.4% compared with similar FeSe2 particles synthe- sized by the conventional method. The growth process of the particles is analyzed and a growth scenario is given. Upon altering the PH values of the water, we observe that the superhydrophobic property is maintained quite consistently across a wide PH range of 1-14. Moreover, the modified particles were also found to be superoleophobic. To the best of our knowledge, there is no systematic research on the wettability of FeSe2 particles, so our research provides a reference for other researchers.展开更多
As environmentally benign and high-efficiency energy storage devices,sodium-ion capacitors(SICs),which combine the merits of batteries and supercapacitors,are considered to have potentially high energy/power densities...As environmentally benign and high-efficiency energy storage devices,sodium-ion capacitors(SICs),which combine the merits of batteries and supercapacitors,are considered to have potentially high energy/power densities and long lifespan.However,the lack of high-rate anodes that can match the high-power-density cathode hinders the commercial application of SICs.In this work,heterostructured Fe/FeSe_(2)/Fe_(3)Se_(4)nanocomposite is pre-pared by chemical vapor deposition(CVD)method and investigated as the anode for SICs.Through heterointerface manipulation,Fe/FeSe_(2)/Fe_(3)Se_(4)demonstrates better sodium ion storage performances than the pure FeSe_(2)and FeSe_(2)/Fe_(3)Se_(4).It can deliver a specific capacity of 484.8 mAh·g^(-1)after 100 cycles at 0.5 A·g^(-1),as well as a good capacity retention.The excellent performance of Fe/FeSe_(2)/Fe_(3)Se_(4)nanocomposite can be ascribed to the synergistic effect of the heterointerface engineered components,where FeSe_(2)and Fe_(3)Se_(4) are responsible for offering a high capacity and metallic Fe can server as mini-current collectors,effec-tively accelerating the electron and charge transfer behavior.Meanwhile,the heterointerface significantly facilitates the sodium ion fast transport,and retards the structural variation during cycling.FeSe-1000//activated carbon(AC)SIC affords a high energy density of 112 Wh·kg^(-1)at 107.5 W·kg^(-1),its power density can achieve 10,750 W·kg^(-1)with remained energy density of 44.2 Wh·kg^(-1),as well as an outstanding cycling stability,demonstrating this effective heterointerface engineered anode strategy for high-performance SICs.展开更多
文摘本文通过气相硒化成功制备了CoSe2/FeSe2@NC异质结复合材料,将未包覆碳层的CoSe2/FeSe2作为对比。当应用于锂离子电池负极材料,CoSe2/FeSe2@NC异质结负极材料相比于CoSe2/FeSe2表现出更为优异的电化学性能。在大电流密度2A g-1循环400圈,仍然保持高可逆容量463.4 mAh g-1。倍率性能测试中在5 A g-1大电流密度下具有420.9 mAh g-1的高放电比容量。CoSe2/FeSe2@NC优异的电化学性能得利于合理的异质结构设计和外部包覆碳层的协同作用,在提高复合材料循环过程中稳定性的同时加快了材料电子-离子传输动力学。
基金Project supported by the Natural Science Foundation of Anhui Province, China （Grant No, 12010202035） and the National Natural Science Foundation of China （Grant No. 51272246）.
文摘Wettability and the light-trapping effect of FeSe2 particles with a micro-nano hierarchical structure have been inves- tigated. Particles are synthesized by an improved solvothermal method, wherein hexadecyl trimetbyl ammonium bromide （CTAB） is employed as a surfactant. After modifying the particles with heptadecafluorodecyltrimethoxy-silane （HTMS）, we find that the water contact angle （WCA） of the FeSe2 particles increases by 6.1~ and the water sliding angle （WSA） decreases by 2.5~ respectively, and the diffuse reflectivity decreases 29.4% compared with similar FeSe2 particles synthe- sized by the conventional method. The growth process of the particles is analyzed and a growth scenario is given. Upon altering the PH values of the water, we observe that the superhydrophobic property is maintained quite consistently across a wide PH range of 1-14. Moreover, the modified particles were also found to be superoleophobic. To the best of our knowledge, there is no systematic research on the wettability of FeSe2 particles, so our research provides a reference for other researchers.
基金financially supported by the Natural Science Foundation of Hebei Province of China(Nos.E2021202011 and E2018202123)Jian-Hua Research Foundation of Hebei University of Technology(No.HB1921)+4 种基金High-strength,Highprecision,Superconducting Rail Transit Aluminum Research and Development and Industrialization Projects(No.2019TSLH0110)"One Belt,One Road"Technology Innovation Cooperation Project of Tianjin(No.18PTZWHZ00220)Ministry of Science and Higher Education of the Russian Federation as part of World-class Research Center program(No.075-15-2020-934)Foundation of Strengthening Program(No.2019-JCJQ-142-00)the Exchange Project of the Third Meeting of the Science and Technology Cooperation Subcommittee of the China-Ukraine Intergovernmental Cooperation Committee(No.CU03-11).
文摘As environmentally benign and high-efficiency energy storage devices,sodium-ion capacitors(SICs),which combine the merits of batteries and supercapacitors,are considered to have potentially high energy/power densities and long lifespan.However,the lack of high-rate anodes that can match the high-power-density cathode hinders the commercial application of SICs.In this work,heterostructured Fe/FeSe_(2)/Fe_(3)Se_(4)nanocomposite is pre-pared by chemical vapor deposition(CVD)method and investigated as the anode for SICs.Through heterointerface manipulation,Fe/FeSe_(2)/Fe_(3)Se_(4)demonstrates better sodium ion storage performances than the pure FeSe_(2)and FeSe_(2)/Fe_(3)Se_(4).It can deliver a specific capacity of 484.8 mAh·g^(-1)after 100 cycles at 0.5 A·g^(-1),as well as a good capacity retention.The excellent performance of Fe/FeSe_(2)/Fe_(3)Se_(4)nanocomposite can be ascribed to the synergistic effect of the heterointerface engineered components,where FeSe_(2)and Fe_(3)Se_(4) are responsible for offering a high capacity and metallic Fe can server as mini-current collectors,effec-tively accelerating the electron and charge transfer behavior.Meanwhile,the heterointerface significantly facilitates the sodium ion fast transport,and retards the structural variation during cycling.FeSe-1000//activated carbon(AC)SIC affords a high energy density of 112 Wh·kg^(-1)at 107.5 W·kg^(-1),its power density can achieve 10,750 W·kg^(-1)with remained energy density of 44.2 Wh·kg^(-1),as well as an outstanding cycling stability,demonstrating this effective heterointerface engineered anode strategy for high-performance SICs.
