酚醛树脂基活性炭微球的制备及其电化学性能

Preparation and electrochemical performance of phenolic resin-based activated carbon microbeads for supercapacitors

以苯酚和甲醛为原料,盐酸为催化剂,制备醇溶性酚醛树脂前驱体,探讨炭化温度对炭微球性能的影响,并将炭微球在3 mol/L HNO3溶液中活化后得到活性炭微球。利用红外光谱、X线衍射(XRD)、扫描电镜(SEM)、循环伏安、恒流充放电、循环寿命等对该材料进行表征及电化学性能测试。研究结果表明:炭微球的最佳炭化温度为750℃,在该温度下制备的炭微球具有良好的球形形貌,其结构为部分石墨化的无定形炭;活性炭微球作为电容器电极材料具有良好的电化学性能,在1 mV/s扫描速度下比电容达到247.8 F/g;在0.5 A/g电流密度充放电下扣式超级电容器比电容高达60 F/g,且充放电循环5 000次后比电容几乎没有衰减。

Alcohol soluble phenolic resin was prepared by using phenol and formaldehyde as starting materials,and hydrochloric acid as catalyst.Carbon microbeads（CMBs） were obtained by decomposition of the phenolic resin at different carbonized temperatures.The as-prepared product was treated in 3 mol/L HNO3 in order to gain the highly activated carbon microbeads（ACMBs）,then the physical and electrochemical properties were studied by infrared spectrometer（IR）,X-ray diffraction（XRD）,scanning electron microscopy（SEM）,cyclic voltammetry,constant current charge-discharge and cycle life measurements.The results show that CMBs with part graphitization have amorphous carbon structure and good spherical morphology at the optimal carbonized temperature of 750 ℃.The electrode made of them has good electrochemical performance and the specific capacitance of ACMB-750 is 247.8 F/g at a scanning rate of 1 mV/s.Meanwhile,the specific capacitance of the button supercapacitor is up to 60 F/g at a charge/discharge current density of 0.5 A/g and the loss of specific capacitance is nearly neglectable after 5 000 cycles.