CAJ | 학술논문

在600℃～1100℃对聚偏二氯乙烯(PVDC)树脂仅进行炭化处理,制备了一系列PVDC基活性炭.由TG、XRD和N_2吸附等温线(77 K)分别测定了PVDC基炭经历的热解过程与其晶型、比表面积和孔结构;采用循环伏安、交流阻抗和恒电流充放电考察了它们在质量分数30%的 KOH水溶液中的电容特性.结果表明:PVDC基炭属于无定形碳,其大的比表面积(874.5m~2/g～969.2m~2/g)和丰富的微孔在固相炭化过程中形成;PVDC基炭具有适于双电层形成的优异孔径分布、高的质量比电容和面积比电容;900℃炭化的PVDC基炭具有最高的比电容值和良好的功率特性,50mA/g电流密度时的放电比电容达256.9F/g,5000mA/g电流密度时的放电比电容保持率达76.5%;提高炭化温度可提高PVDC基炭的电导率,降低电解质离子在孔内的扩散阻抗,改善双电层电容器的功率性能.
재600℃～1100℃대취편이록을희(PVDC)수지부진행탄화처리,제비료일계렬PVDC기활성탄.유TG、XRD화N_2흡부등온선(77 K)분별측정료PVDC기탄경력적열해과정여기정형、비표면적화공결구;채용순배복안、교류조항화항전류충방전고찰료타문재질량분수30%적 KOH수용액중적전용특성.결과표명:PVDC기탄속우무정형탄,기대적비표면적(874.5m~2/g～969.2m~2/g)화봉부적미공재고상탄화과정중형성;PVDC기탄구유괄우쌍전층형성적우이공경분포、고적질량비전용화면적비전용;900℃탄화적PVDC기탄구유최고적비전용치화량호적공솔특성,50mA/g전류밀도시적방전비전용체256.9F/g,5000mA/g전류밀도시적방전비전용보지솔체76.5%;제고탄화온도가제고PVDC기탄적전도솔,강저전해질리자재공내적확산조항,개선쌍전층전용기적공솔성능.
A series of poly vinylidene chloride (PVDC) based activated carbons was prepared by carbonization at 600-1 100 ℃. Their formation, crystallinity, surface area and pore structure were characterized by thermogravimetry, X-ray diffraction and nitrogen adsorption. The electrochemical performance was investigated by cycle voltammetry, AC impedance and galvanostatic charge/discharge in a 30 % (mass fraction) KOH electrolyte. Results showed that the structure of PVDC-based carbons was amorphous and their high surface area (874-969 m~2/g) and abundant micropores were formed during the solid phase carbonization. PVDC-based carbon had a high gravimetric capacitance and specific capacitance per surface area, owing to its optimum pore size distribution suitable for the formation of electric double layers. The PVDC-based carbon heat-treated at 900 ℃ had a maximum capacitance and an excellent power performance. The specific capacitance can reach as high as 256.9 F/g at low discharge current density (50 mA/g) and the capacitance retention ratio is 76.5% at high current density (5 000 mA/g). The electrical conductivity of PVDC-based carbon increased and the diffusion resistance of electrolyte ions in pores decreased with increasing carbonization temperature, and the rate performance of the electric double layer capacitor is improved as a result.