Organic materials, especially the carbonyl compounds, are promising anode materials for room temperature sodium-ion batteries owing to their high reversible capacity, structural diversity as well as eco-friendly synth...Organic materials, especially the carbonyl compounds, are promising anode materials for room temperature sodium-ion batteries owing to their high reversible capacity, structural diversity as well as eco-friendly synthesis from bio-mass. Herein, we report a novel anthraquinone derivative, C_(14)H_6 O_4 Na_2 composited with carbon nanotube(C_(14)H_6 O_4 Na_2-CNT), used as an anode material for sodium-ion batteries in etherbased electrolyte. The C_(14)H_6 O_4 Na_2-CNT electrode delivers a reversible capacity of 173 mAh g^(-1) and an ultra-high initial Coulombic efficiency of 98% at the rate of 0.1 C. The capacity retention is 82% after 50 cycles at 0.2 C and a good rate capability is displayed at 2 C.Furthermore, the average Na insertion voltage of 1.27 V vs. Na^+/Na makes it a unique and safety battery material, which would avoid Na plating and formation of solid electrolyte interface. Our contribution provides new insights for designing developed organic anode materials with high initial Coulombic efficiency and improved safety capability for sodium-ion batteries.展开更多
Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)s...Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)spheres,used as anode material for lithium ion batteries,were successfully fabricated by Stober method.XRD patterns reveal that Fe3O4@TiO2@C Y-S spheres possess a good crystallinity.But the diffraction peaks’intensity of Fe3O4 crystals in the composites is much weaker than that of bare Fe3O4 spheres,indicating that the outer anatase TiO2@C layer can cover up the diffraction peaks of inner Fe3O4 spheres.The yolk-shell structure of Fe3O4@TiO2@C spheres is further characterized by TEM,HAADFSTEM,and EDS mapping.The yolk-shell structure is good for improving the cycling stability of the inner Fe3O4 spheres during lithium ions insertion-extraction processes.When tested at 200 mA/g,the Fe3O4@TiO2@C Y-S spheres can provide a stable discharge capacity of 450 mAh/g over 100 cycles,which is much better than that of bare Fe3O4 spheres and TiO2@C spheres.Furthermore,cyclic voltammetry curves show that the composites have a good cycling stability compared to bare Fe3O4 spheres.展开更多
Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion k...Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion kinetics. An SnS_2@carbon hollow nanospheres(SnS_2@C) has been designed and fabricated via a facile solvothermal route, followed by an annealing treatment. The SnS_2@C hybrid possesses an ideal hollow structure, rich active sites, a large electrode/electrolyte interface, a shortened ion transport pathway, and, importantly, a bu er space for volume change, generated from the repeated insertion/extraction of sodium ions. These merits lead to the significant reinforcement of structural integrity during electrochemical reactions and the improvement in sodium storage properties, with a high specific reversible capacity of 626.8 mAh g^(-1) after 200 cycles at a current density of 0.2 A g^(-1) and superior high-rate performance(304.4 mAh g^(-1) at 5 A g^(-1)).展开更多
基金supported by funding from the National Key Technologies R&D Program (2016YFB0901500)the NSFC (11234013 and 51421002)the One Hundred Talent Project of the Chinese Academy of Sciences
文摘Organic materials, especially the carbonyl compounds, are promising anode materials for room temperature sodium-ion batteries owing to their high reversible capacity, structural diversity as well as eco-friendly synthesis from bio-mass. Herein, we report a novel anthraquinone derivative, C_(14)H_6 O_4 Na_2 composited with carbon nanotube(C_(14)H_6 O_4 Na_2-CNT), used as an anode material for sodium-ion batteries in etherbased electrolyte. The C_(14)H_6 O_4 Na_2-CNT electrode delivers a reversible capacity of 173 mAh g^(-1) and an ultra-high initial Coulombic efficiency of 98% at the rate of 0.1 C. The capacity retention is 82% after 50 cycles at 0.2 C and a good rate capability is displayed at 2 C.Furthermore, the average Na insertion voltage of 1.27 V vs. Na^+/Na makes it a unique and safety battery material, which would avoid Na plating and formation of solid electrolyte interface. Our contribution provides new insights for designing developed organic anode materials with high initial Coulombic efficiency and improved safety capability for sodium-ion batteries.
基金supported by the Tianjin Committee of Science and Technology (No.14JCZDJC32400)Tianjin Science and Technology Innovation Platform Program (No.14TXGCCX00017)
文摘Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)spheres,used as anode material for lithium ion batteries,were successfully fabricated by Stober method.XRD patterns reveal that Fe3O4@TiO2@C Y-S spheres possess a good crystallinity.But the diffraction peaks’intensity of Fe3O4 crystals in the composites is much weaker than that of bare Fe3O4 spheres,indicating that the outer anatase TiO2@C layer can cover up the diffraction peaks of inner Fe3O4 spheres.The yolk-shell structure of Fe3O4@TiO2@C spheres is further characterized by TEM,HAADFSTEM,and EDS mapping.The yolk-shell structure is good for improving the cycling stability of the inner Fe3O4 spheres during lithium ions insertion-extraction processes.When tested at 200 mA/g,the Fe3O4@TiO2@C Y-S spheres can provide a stable discharge capacity of 450 mAh/g over 100 cycles,which is much better than that of bare Fe3O4 spheres and TiO2@C spheres.Furthermore,cyclic voltammetry curves show that the composites have a good cycling stability compared to bare Fe3O4 spheres.
基金the National Natural Science Foundation of China (Grant No. 21701144)the China Postdoctoral Science Foundation (Grant Nos. 2016M592303 and 2017T100536)
文摘Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion kinetics. An SnS_2@carbon hollow nanospheres(SnS_2@C) has been designed and fabricated via a facile solvothermal route, followed by an annealing treatment. The SnS_2@C hybrid possesses an ideal hollow structure, rich active sites, a large electrode/electrolyte interface, a shortened ion transport pathway, and, importantly, a bu er space for volume change, generated from the repeated insertion/extraction of sodium ions. These merits lead to the significant reinforcement of structural integrity during electrochemical reactions and the improvement in sodium storage properties, with a high specific reversible capacity of 626.8 mAh g^(-1) after 200 cycles at a current density of 0.2 A g^(-1) and superior high-rate performance(304.4 mAh g^(-1) at 5 A g^(-1)).
