In order to improve the electrochemical performance of polyoxomolybdate Na3[AlMo6O24H6]（NAM） as the cathode material of lithium ion battery, the NAM materials with small particle size were synthesized by elevatingth...In order to improve the electrochemical performance of polyoxomolybdate Na3[AlMo6O24H6]（NAM） as the cathode material of lithium ion battery, the NAM materials with small particle size were synthesized by elevatingthe synthesistemperaturein the solution.The as-prepared NAM materials were investigated by FT-IR, XRD, SEM and EIS. Their discharge-charge and cycle performance were also tested. The resultsshowthat the particle size decreasesto less than10μm at the temperature ofhigher than 40℃.When synthesized at 80℃,the NAMwiththe smallest particle size （-3μm）exhibitsthe best electrochemical performance such ashigh initial discharge capacity of 409 mA·h/gandcoulombic efficiency of 95% in the first cycle at 0.04C.展开更多
The robust porous architectures of active materials are highly desired for oxygen electrodes in lithium–oxygen batteries to enable high capacities and excellent reversibility. Herein, we report a novel three-dimensio...The robust porous architectures of active materials are highly desired for oxygen electrodes in lithium–oxygen batteries to enable high capacities and excellent reversibility. Herein, we report a novel three-dimensional replication strategy to fabricate three-dimensional architecture of porous carbon for oxygen electrodes in lithium–oxygen batteries. As a demonstration, ball-flower-like carbon microspheres assembled with tortuous hollow carbon nanosheets are successfully prepared by completely replicating the morphology of the nanostructured zinc oxide template and utilizing the polydopamine coating layer as the carbon source.When used as the active material for oxygen electrodes, the three-dimensional porous architecture of the prepared ballflower-like carbon microspheres can accommodate the discharge product lithium peroxide and simultaneously maintain the ions and gas diffusion paths. Moreover, their high degrees of defectiveness by nitrogen doping provide sufficient active sites for oxygen reduction/evolution reaction.Thus the prepared ball-flower-like carbon microspheres demonstrate a high capacity of 9,163.7 mA h g-1 and excellent reversibility. This work presents an effective way to prepare three-dimensional architectures of porous carbon by replicating the controllable nanostructures of transition metal oxide templates for energy storage and conversion applications.展开更多
Organic lithium-ion batteries（OLIBs） represent a new generation of power storage approach for their environmental benignity and high theoretical specific capacities.However, it has the disadvantage with regard to th...Organic lithium-ion batteries（OLIBs） represent a new generation of power storage approach for their environmental benignity and high theoretical specific capacities.However, it has the disadvantage with regard to the dissolution of active materials in organic electrolyte. In this study, we encapsulated high capacity material calix[4]quinone（C4Q） in the nanochannels of ordered mesoporous carbon（OMC）CMK-3 with various mass ratios ranging from 1：3 to 3：1, and then systematically investigated their morphology and electrochemical properties. The nanocomposites characterizations confirmed that C4Q is almost entirely capsulated in the nanosized pores of the CMK-3 while the mass ratio is less than2：1. As cathodes in lithium-ion batteries, the C4Q/CMK-3（1：2） nanocomposite exhibits optimal initial discharge capacity of 427 mA h g^（-1） with 58.7% cycling retention after 100 cycles. Meanwhile, the rate performance is also optimized with a capacity of 170.4 mA h g^（-1） at 1 C. This method paves a new way to apply organic cathodes for lithium-ion batteries.展开更多
文摘In order to improve the electrochemical performance of polyoxomolybdate Na3[AlMo6O24H6]（NAM） as the cathode material of lithium ion battery, the NAM materials with small particle size were synthesized by elevatingthe synthesistemperaturein the solution.The as-prepared NAM materials were investigated by FT-IR, XRD, SEM and EIS. Their discharge-charge and cycle performance were also tested. The resultsshowthat the particle size decreasesto less than10μm at the temperature ofhigher than 40℃.When synthesized at 80℃,the NAMwiththe smallest particle size （-3μm）exhibitsthe best electrochemical performance such ashigh initial discharge capacity of 409 mA·h/gandcoulombic efficiency of 95% in the first cycle at 0.04C.
基金supported by grants from the National Natural Science Foundation of China (21673169 and 51672205)the National Key R&D Program of China (2016YFA0202602)+1 种基金the Research Start-Up Fund from Wuhan University of Technologythe Fundamental Research Funds for the Central Universities (WUT: 2017IB005, 2016IVA083)
文摘The robust porous architectures of active materials are highly desired for oxygen electrodes in lithium–oxygen batteries to enable high capacities and excellent reversibility. Herein, we report a novel three-dimensional replication strategy to fabricate three-dimensional architecture of porous carbon for oxygen electrodes in lithium–oxygen batteries. As a demonstration, ball-flower-like carbon microspheres assembled with tortuous hollow carbon nanosheets are successfully prepared by completely replicating the morphology of the nanostructured zinc oxide template and utilizing the polydopamine coating layer as the carbon source.When used as the active material for oxygen electrodes, the three-dimensional porous architecture of the prepared ballflower-like carbon microspheres can accommodate the discharge product lithium peroxide and simultaneously maintain the ions and gas diffusion paths. Moreover, their high degrees of defectiveness by nitrogen doping provide sufficient active sites for oxygen reduction/evolution reaction.Thus the prepared ball-flower-like carbon microspheres demonstrate a high capacity of 9,163.7 mA h g-1 and excellent reversibility. This work presents an effective way to prepare three-dimensional architectures of porous carbon by replicating the controllable nanostructures of transition metal oxide templates for energy storage and conversion applications.
基金supported by the National Natural Science Foundation of China (21403187)the Natural Science Foundation of Hebei Province of China (B2015203124)the Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Nankai University
文摘Organic lithium-ion batteries（OLIBs） represent a new generation of power storage approach for their environmental benignity and high theoretical specific capacities.However, it has the disadvantage with regard to the dissolution of active materials in organic electrolyte. In this study, we encapsulated high capacity material calix[4]quinone（C4Q） in the nanochannels of ordered mesoporous carbon（OMC）CMK-3 with various mass ratios ranging from 1：3 to 3：1, and then systematically investigated their morphology and electrochemical properties. The nanocomposites characterizations confirmed that C4Q is almost entirely capsulated in the nanosized pores of the CMK-3 while the mass ratio is less than2：1. As cathodes in lithium-ion batteries, the C4Q/CMK-3（1：2） nanocomposite exhibits optimal initial discharge capacity of 427 mA h g^（-1） with 58.7% cycling retention after 100 cycles. Meanwhile, the rate performance is also optimized with a capacity of 170.4 mA h g^（-1） at 1 C. This method paves a new way to apply organic cathodes for lithium-ion batteries.
