喷墨打印法制备MnO_2薄膜电极的超电容性能

Supercapacitance of MnO_2 Thin Film Electrodes Prepared Using Jet Printing Method

在碱性条件下用KMnO_4氧化MnSO_4制备得到粒径约小于200 nm的MnO_2微粒.将MnO_2粉末、乙炔黑、分散剂Lomar-D、粘度控制剂乙醇胺、粘结剂羧甲基纤维素钠(CMCS)及去离子水按质量比200:40:4:1:1:4000混合,超声分散得到稳定的"墨水"体系.用计算机喷墨打印得到MnO_2超薄电极.SEM测试结果表明电极表面均匀,厚度约为2.5μm.循环伏安法和恒电流充放电实验结果表明,在1 mol·L^(-1)Li_2SO_4溶液中,电位区间为0-0.85 V(vs SCE)内MnO_2超薄电极表现出优良的超电容性能.在以9.4 A·g^(-1)充放电时,MnO_2超薄电极的放电比电容为154 F·g^(-1),循环2000周后,电容量几乎不变.

MnO2 particles in the size less than 200 nm were prepared via the oxidation of MnSO4 using KMnO4 as oxidizer.The printing ＇ink＇ was prepared by mixing MnO2 particles with acetylene black,dispersion additive Lomar-D, ethanolamine,binder CMCS and distilled water in the mass ratio of 200：40：4：1：1：4000,and dispersing under ultrasonic. The ultra thin MnO2 film electrodes were prepared by means of computer jet printing technique using this ＇ink＇.The SEM images showed that the surface of the ultra thin MnO2 film electrode was uniform,and its thickness was about 2.5μm.In 1 mol·L^-1 Li2SO4 solution the electrodes present typical electrochemical supercapacitance behavior observed by voltammetry and charge-discharge measurements,in the potential region of 0-0.85 V（vs SCE）.Its specific capacitance reached to 154 F·g^-1 at the discharge current of 9.4 A·g^-1,and remained almost no change after 2000 cycles.