采用水热法成功合成了一种新型氮掺杂碳修饰MnO2纳米带(MnO2@NC)。将该材料作为锂离子电池负极时,在2 A g-1的大电流密度下循环1000次后,其可逆比容量可达310.4 mAh g-1,并展现出卓越的倍率并能。与未改性MnO2相比,MnO2@NC表现出更好的...采用水热法成功合成了一种新型氮掺杂碳修饰MnO2纳米带(MnO2@NC)。将该材料作为锂离子电池负极时,在2 A g-1的大电流密度下循环1000次后,其可逆比容量可达310.4 mAh g-1,并展现出卓越的倍率并能。与未改性MnO2相比,MnO2@NC表现出更好的倍率性能、更高的比容量和容量保持率。电化学测试分析表明,MnO2@NC电化学性能提高的原因在于电荷转移电阻的降低、缩短的Li+扩散距离以及更为优异的电极动力学。?展开更多
The commercialization of electrolytic MnO_(2)-Zn batteries is highly applauded owing to the advantages of cost-effectiveness,high safety,high energy density,and durable working performance.However,due to the low rever...The commercialization of electrolytic MnO_(2)-Zn batteries is highly applauded owing to the advantages of cost-effectiveness,high safety,high energy density,and durable working performance.However,due to the low reversibility of the cathode MnO_(2)/Mn^(2+)chemistry at high areal capacities and the severe Zn anode corrosion,the practical application of MnO_(2)-Zn batteries is hampered by inadequate lifespan.Leveraging the full advantage of an iodine redox mediator,here we design a highly rechargeable electrolytic MnO_(2)-Zn battery with a high areal capacity.The MnO_(2)-Zn battery coupled with an iodine mediator in a mild electrolyte shows a high discharge voltage of 1.85 V and a robust areal capacity of 10 mAh cm^(-2)under a substantial discharge current density of 160 mA cm^(-2).The MnO_(2)/I_(2)-Zn battery with an areal capacity of 10 mAh cm^(-2)exhibits prolonged stability of over 950 cycles under a high-capacity retention of~94%.The scaled-up MnO_(2)/I_(2)-Zn battery reveals a stable cycle life under a cell capacity of~600 mAh.Moreover,our constructed MnO_(2)/I_(2)-Zn battery demonstrates a practical energy density of~37 Wh kg^(-1)and a competitive energy cost of<18 US$kWh^(-1)by taking into account the cathode,anode,and electrolyte.The MnO_(2)/I_(2)-Zn battery,with its remarkable reversibility and reasonable energy density,enlightens a new arena of large-scale energy storage devices.展开更多
γ-Fe nano-particles with size of 20-40 nm were produced by SF6-sensitized CW CO2 laser-induced gaseous pyrolysis of Fe(Co) 5, The γ-Fe stabte in reaction zone at above 910℃ was formed.The rapid quenching prevents f...γ-Fe nano-particles with size of 20-40 nm were produced by SF6-sensitized CW CO2 laser-induced gaseous pyrolysis of Fe(Co) 5, The γ-Fe stabte in reaction zone at above 910℃ was formed.The rapid quenching prevents from the γ-Fe transforming to α-Fe as rapidly cooling from high temperature to room temperature, The characteristics of the particles were examined at room temperature by TEM. electron diffraction and XRD. It was proved that about 70% of γ-Fe phase in the particles was present. In addition. the lattice constant of the γ-Fe was 0.364 nm in place of 0.360 nm展开更多
Nanopowder MnO 2 was prepared with two oxidation reduction methods.XRD,SEM,FT IR and surface area measurement techniques were used to investigate properties of the MnO 2 powder.The results showed that the nano MnO 2 w...Nanopowder MnO 2 was prepared with two oxidation reduction methods.XRD,SEM,FT IR and surface area measurement techniques were used to investigate properties of the MnO 2 powder.The results showed that the nano MnO 2 with an average diameter in 30～50nm and good dispersity and high catalytic activity for H 2O 2 decomposition,can be synthesized with the two methods.With reduced crystal size of the powder,the infrared absorption peak of Mn O bond was blue shifted and fissioned,one shifted 61 19cm -1 and the other shifted 11 15cm -1 ,and the characteristic vibration bands of adsorption water were also blue shifted.展开更多
文摘采用水热法成功合成了一种新型氮掺杂碳修饰MnO2纳米带(MnO2@NC)。将该材料作为锂离子电池负极时,在2 A g-1的大电流密度下循环1000次后,其可逆比容量可达310.4 mAh g-1,并展现出卓越的倍率并能。与未改性MnO2相比,MnO2@NC表现出更好的倍率性能、更高的比容量和容量保持率。电化学测试分析表明,MnO2@NC电化学性能提高的原因在于电荷转移电阻的降低、缩短的Li+扩散距离以及更为优异的电极动力学。?
基金W.C.acknowledges the startup funds from USTC(Grant#KY2060000150)the Fundamental Research Funds for the Central Universities(WK2060000040).
文摘The commercialization of electrolytic MnO_(2)-Zn batteries is highly applauded owing to the advantages of cost-effectiveness,high safety,high energy density,and durable working performance.However,due to the low reversibility of the cathode MnO_(2)/Mn^(2+)chemistry at high areal capacities and the severe Zn anode corrosion,the practical application of MnO_(2)-Zn batteries is hampered by inadequate lifespan.Leveraging the full advantage of an iodine redox mediator,here we design a highly rechargeable electrolytic MnO_(2)-Zn battery with a high areal capacity.The MnO_(2)-Zn battery coupled with an iodine mediator in a mild electrolyte shows a high discharge voltage of 1.85 V and a robust areal capacity of 10 mAh cm^(-2)under a substantial discharge current density of 160 mA cm^(-2).The MnO_(2)/I_(2)-Zn battery with an areal capacity of 10 mAh cm^(-2)exhibits prolonged stability of over 950 cycles under a high-capacity retention of~94%.The scaled-up MnO_(2)/I_(2)-Zn battery reveals a stable cycle life under a cell capacity of~600 mAh.Moreover,our constructed MnO_(2)/I_(2)-Zn battery demonstrates a practical energy density of~37 Wh kg^(-1)and a competitive energy cost of<18 US$kWh^(-1)by taking into account the cathode,anode,and electrolyte.The MnO_(2)/I_(2)-Zn battery,with its remarkable reversibility and reasonable energy density,enlightens a new arena of large-scale energy storage devices.
文摘γ-Fe nano-particles with size of 20-40 nm were produced by SF6-sensitized CW CO2 laser-induced gaseous pyrolysis of Fe(Co) 5, The γ-Fe stabte in reaction zone at above 910℃ was formed.The rapid quenching prevents from the γ-Fe transforming to α-Fe as rapidly cooling from high temperature to room temperature, The characteristics of the particles were examined at room temperature by TEM. electron diffraction and XRD. It was proved that about 70% of γ-Fe phase in the particles was present. In addition. the lattice constant of the γ-Fe was 0.364 nm in place of 0.360 nm
文摘Nanopowder MnO 2 was prepared with two oxidation reduction methods.XRD,SEM,FT IR and surface area measurement techniques were used to investigate properties of the MnO 2 powder.The results showed that the nano MnO 2 with an average diameter in 30～50nm and good dispersity and high catalytic activity for H 2O 2 decomposition,can be synthesized with the two methods.With reduced crystal size of the powder,the infrared absorption peak of Mn O bond was blue shifted and fissioned,one shifted 61 19cm -1 and the other shifted 11 15cm -1 ,and the characteristic vibration bands of adsorption water were also blue shifted.
