摘要
利用碳球为还原剂,在中性KMnO4溶液中制备出MnO2/碳球复合材料,并对其结构和电化学性能进行了研究。结果显示,随着碳球含量的增加,MnO2/碳球复合材料的循环稳定性提高,但比电容量降低;当碳球质量分数为35%时,MnO2/碳球复合材料的比电容量在50 mA/g的电流密度下达到181 F/g。分别采用KOH活化和混酸氧化的碳球为还原剂,可以有效地提高MnO2/碳球复合材料的比电容量和循环稳定性,相应复合材料的比电容量分别达到192 F/g和218 F/g,而且经过500次的充放电测试,仍然保持为184 F/g和192 F/g。
MnO2/carbon sphere composites(MnO2/CS composites) have been prepared in neutral KMnO4solution using CS as a reducing reagent.The structures and electrochemical properties of the composites were investigated.The results reveal that the cycling stability of MnO2/CS composites electrodes is improved with increasing CS content,while the specific capacitance decreases.The specific capacitance of a composite containing 35% mass fraction of CS was 181 F/g at a current density of 50 mA/g.The stability and capacitance of the composite electrodes were greatly improved by using KOH-activated or acid-oxidized CS;the corresponding specific capacitances of the composite electrodes were increased to 192 F/g and 218 F/g,respectively.Furthermore,the values remained as high as 184 F/g and 192 F/g respectively,after 500 times charge-discharge cycles.MnO2/CS composites containing pre-treated CS exhibit excellent capacitance characteristics as supercapacitor electrode materials.
出处
《北京化工大学学报（自然科学版）》
CAS
CSCD
北大核心
2014年第2期41-47,共7页
Journal of Beijing University of Chemical Technology(Natural Science Edition)
基金
中央高校基本科研业务费(505564)
