CAJ | 학술논문

采用具有不同孔径分布的活性炭作为电极材料,研究了离子尺寸与孔结构对电容性能的影响.结果表明,正负极表现出不对称的电容行为,正负极的质量比电容分别为113和7 F·g-1.在负极电位区间,循环伏安曲线的响应电流明显减小.材料表面最大电荷存储量的理论计算与实验结果有着很好的一致性,这些结果表明用于阳离子电荷存储的电极孔隙空间不够发达,导致电容器在充电过程中负极材料表面达到电荷饱和状态,进而表现出较差的电容行为,然而,四氟硼酸根阴离子可以进入到正极电极材料大多数孔道中,电极未发生电荷饱和效应,表现出优异的电容行为,负极较低的比电容将会影响电容器的整体性能,因此,正负极应当根据离子尺寸与电极材料孔结构的构效关系进行匹配,以使电容器的比电容最大化.
채용구유불동공경분포적활성탄작위전겁재료,연구료리자척촌여공결구대전용성능적영향.결과표명,정부겁표현출불대칭적전용행위,정부겁적질량비전용분별위113화7 F·g-1.재부겁전위구간,순배복안곡선적향응전류명현감소.재료표면최대전하존저량적이론계산여실험결과유착흔호적일치성,저사결과표명용우양리자전하존저적전겁공극공간불구발체,도치전용기재충전과정중부겁재료표면체도전하포화상태,진이표현출교차적전용행위,연이,사불붕산근음리자가이진입도정겁전겁재료대다수공도중,전겁미발생전하포화효응,표현출우이적전용행위,부겁교저적비전용장회영향전용기적정체성능,인차,정부겁응당근거리자척촌여전겁재료공결구적구효관계진행필배,이사전용기적비전용최대화.
We reported on the capacitive behaviors regarding to the relationship between ion size and pore architecture,using activated carbons with an adjusted pore structure as electrode materials.The results revealed that an asymmetric capacitance response occurred in both electrodes.The gravimetric capacitances for the positive and negative electrodes were 113 and 7 F.g-1,respectively.A significant current decay was presented in the negative region of cyclic voltammetry curve.Experimental and calculated maximum storage charges had a good agreement.This results suggested that the insufficiently developed pore architecture for cation accommodation led to a saturation effect on the active surface,consequently,a deteriorated capacitive performance in the negative electrode.Contrarily,when pore size was larger than tetrafluoroborate dimension,the saturation effect was not found.However,this was at the expense of the lower specific area capacitance in the positive electrode.The poor capacitive behavior of the negative electrode would limit the usable voltage of the cell system and consequently the deliverable energy and power.As a result,an optimal match between the pores size and the ion dimension with respect to each electrode would be considered to obtain the maximum capacitance for the capacitor unit.