反应性硬模板制备多孔氮掺杂碳的电化学性能

Electrochemical performances of porous nitrogen-doped carbons prepared by reactive hard templates

以葡萄糖(G)、尿素(U)、碱式碳酸盐和碳酸钾(PC)分别为碳前驱体、氮掺杂剂、反应性硬模板和活化剂,采用模板碳化-化学活化法合成了层级多孔氮掺杂碳材料。研究了各前驱体质量比、硬模板类型对其结构进而对其用作超级电容器电极性能的影响。结果表明:在800℃裂解温度下,G、U、碱式碳酸锌(BZC)和PC的质量比为2∶1∶2∶2时,制备的多孔氮掺杂碳(G/U-BZC-PC)呈现出珊瑚状、多级孔(微-介),具有大的比表面积(3000 m^(2)/g)、较高的石墨化程度以及低的电荷转移电阻;在1 A/g电流密度下,其扣式电池(6 mol/L KOH)的比电容为301.9 F/g,且具有较好的倍率性能,增大至10 A/g时,其电容保持率为89.4%;另外,在10000次充放电循环后,其电容保持率为98.1%。

The nitrogen-doped carbon materials with hierarchical pores were synthesized by template carbonization-chemical activation by using glucose(G),urea(U),basic carbonates and potassium carbonate(PC)as the carbon precursor,nitrogen dopant,reactive hard template and activating agent,respectively.The effects of the mass ratio of precursors and type of hard templates on the structure and performances as the supercapacitor electrode were studied.The results show that when the pyrolysis temperature is 800℃and the mass ratio of G,U,basic zinc carbonate(BZC)and PC is 2∶1∶2∶2,the obtained G/U-BZC-PC presents coral-like appearance and hierarchically porous structure(micro/mesopore),and has large surface area(3000 m^(2)/g),high graphitization degree and low charge transfer resistance.The specific capacitance of the button battery(6 mol/L KOH)reaches 301.9 F/g at 1 A/g,and the capacitance retention is 89.4%with increase of current density to 10 A/g,exhibiting the good rate capability.In addition,the capacitance retention is 98.1%after 10000 cycles.