物理化学学报
物理化學學報
물이화학학보
ACTA PHYSICO-CHIMICA SINICA
2012年
2期
387-392
,共6页
张国梁%赵丹%郭培志%位忠斌%赵修松
張國樑%趙丹%郭培誌%位忠斌%趙脩鬆
장국량%조단%곽배지%위충빈%조수송
电极%电容量%Co3O4%纳米线%丙三醇
電極%電容量%Co3O4%納米線%丙三醇
전겁%전용량%Co3O4%납미선%병삼순
Electrode%Capacitance%Co3O4%Nanowire%Glycerol
以硝酸钴和丙三醇为反应物通过反应条件的改变控制制备出Co3O4纳米线.利用粉末X射线衍射(XRD),扫描电子显微镜(SEM)和透射电子显微镜(TEM)对产物的形貌与结构进行了表征.实验发现,在低扫描速率下,Co3O4纳米线电及的循环伏安(CV)曲线呈现出两对氧化还原峰.恒电流充放电实验中,氧化钴纳米线电极在1A·g-1电流密度下的电容为163 F·g-1;在1和4A·g-1条件下,其容量随循环次数的增加先上升后下降,1000次充放电循环后容量保持率分别在98%和80%以上,继续增加循环次数则容量下降比较明显.锂离子电池性质测试中,氧化钴纳米线的放电容量为1124 mAh·g-1,然而放电容量随循环次数增加下降较快.基于实验结果,对Co3O4纳米线的形成机理及其结构与电化学性质之间的关系进行了探讨.
以硝痠鈷和丙三醇為反應物通過反應條件的改變控製製備齣Co3O4納米線.利用粉末X射線衍射(XRD),掃描電子顯微鏡(SEM)和透射電子顯微鏡(TEM)對產物的形貌與結構進行瞭錶徵.實驗髮現,在低掃描速率下,Co3O4納米線電及的循環伏安(CV)麯線呈現齣兩對氧化還原峰.恆電流充放電實驗中,氧化鈷納米線電極在1A·g-1電流密度下的電容為163 F·g-1;在1和4A·g-1條件下,其容量隨循環次數的增加先上升後下降,1000次充放電循環後容量保持率分彆在98%和80%以上,繼續增加循環次數則容量下降比較明顯.鋰離子電池性質測試中,氧化鈷納米線的放電容量為1124 mAh·g-1,然而放電容量隨循環次數增加下降較快.基于實驗結果,對Co3O4納米線的形成機理及其結構與電化學性質之間的關繫進行瞭探討.
이초산고화병삼순위반응물통과반응조건적개변공제제비출Co3O4납미선.이용분말X사선연사(XRD),소묘전자현미경(SEM)화투사전자현미경(TEM)대산물적형모여결구진행료표정.실험발현,재저소묘속솔하,Co3O4납미선전급적순배복안(CV)곡선정현출량대양화환원봉.항전류충방전실험중,양화고납미선전겁재1A·g-1전류밀도하적전용위163 F·g-1;재1화4A·g-1조건하,기용량수순배차수적증가선상승후하강,1000차충방전순배후용량보지솔분별재98%화80%이상,계속증가순배차수칙용량하강비교명현.리리자전지성질측시중,양화고납미선적방전용량위1124 mAh·g-1,연이방전용량수순배차수증가하강교쾌.기우실험결과,대Co3O4납미선적형성궤리급기결구여전화학성질지간적관계진행료탐토.
Cobalt oxide (Co3O4) nanowires were controllably synthesized using glycerol and Co(NO3)2 as reagents and adjustment of the experimental parameters.The morphology and structure of the asprepared products were characterized by a series of techniques such as X-ray podwer diffraction (XRD),scanning electron microscopy (SEM),and transmission electron microscopy (TEM).Electrochemical performance of the nanowires was studied by cyclic voltammetry (CV) and galvanostatic charge-discharge measurements.It was found that two pairs of redox peaks appeared in the CV curves of Co3O4 nanowire electrodes at low scan rates.The specific capacitance of the Co3O4 nanowire electrodes was 163 F·g-1 at a current density of 1 A· g-1,according to the galvanostatic charge-discharge measurements.Cycle stability tests showed that the specific capacitance increased over the first tens of cycles and then reduced slowly.After 1000 cycles,the capacitance retention was over 98% at 1 A· g-1 and 80% at 4 A· g-1; it then decreased obviously with further increase in cycle number.In Li-ion battery measurements,Co3O4 nanowire electrodes showed a discharge capacitance of 1124 mAh·g-1 which decreased rapidly during the cycle test.The formation mechanism and the relationship between the structure and electrochemical properties of Co3O4 nanowires were discussed based on the experimental results.