Supercapacitor Performance of Hydrous Ruthenium Oxide Electrodes Prepared by Electrophoretic Deposition
Supercapacitor Performance of Hydrous Ruthenium Oxide Electrodes Prepared by Electrophoretic Deposition
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DOI：
10.1149/1.2138672
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发表时间：
2006-02
影响因子：
3.9
通讯作者：
J. Jang;Akiko Kato;K. Machida;K. Naoi
中科院分区：
文献类型：
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作者：
J. Jang;Akiko Kato;K. Machida;K. Naoi
在不添加粘结剂和碳添加剂的情况下，采用电泳法制备了水合氧化Ru电极。通过EPD和250°C的热处理，得到了具有多孔结构(堆积密度约为1.9g/cm3)的纳米颗粒网络(约10 nm)。获得了高比电容(I MV/S时为734F/g和50 MV/S时为608F/g)，比能量和比功率分别高达25Wh/kg(92W/kg)和21kW/kg(12Wh/kg)，负载重量为0.19 mg/cm2。在较高的负载量(>；0.4 mg/cm2)下，比电容逐渐减小。此外，体积能很高，因为没有使用低密度添加剂，如多孔炭和粘结剂。由电化学阻抗谱计算的比能量和比功率与循环伏安法测得的值吻合较好。随着电极厚度的增加，倍率容量的下降可以通过时间常数(τ)的分布来关联，该时间常数是利用具有多个Warburg元件的等效电路从阻抗谱计算得到的。
Electrodes of hydrous ruthenium oxide were prepared by electrophoretic deposition (EPD) without binder and carbon additives. Through EPD and heat-treatment (250°C), a network of nanoparticles (ca. 10 nm) was developed with porous structure (packing density ca. 1.9 g/cm 3 ). As a result, high specific capacitance (734 F/g at I mV/s and 608 F/g at 50 mV/s) was obtained, where specific energy and power were as high as 25 Wh/kg (at 92 W/kg) and 21 kW/kg (at 12 Wh/kg), with loading weight of 0.19 mg/cm 2 . At higher loading weight (>0.4 mg/cm 2 ), specific capacitance decreased gradually. Also, volumetric energy was high because low-density additives, such as porous carbon and binder, were not used. From electrochemical impedance spectroscopy, specific energy and power were calculated, showing good agreement with values measured by CV. The decrease of rate capability with thicker electrode could be correlated by distribution of the time constant (τ), which was calculated from impedance spectra by using an equivalent circuit with multiple Warburg elements.