Potential Characteristics of Supercapacitor Based on Ruthenium Oxide-Aqueous Electrolyte

The electrode for a supercapacitor was prepared using an amorphous ruthenium oxide, which was synthesized from ruthenium trichloride hydrate$(RuO_2{\cdot}nH_2O)$. A supercapacitor was assembled with an electrode of ruthenium oxide material on a current collector of tantalum, and an electrolyte of 4.8 M sulfuric acid. The result of the AC impedance analyses on $Ta/H_2SO_4(4.8 M)/Pt$ cell showed that tantalum was stable at the potential range of $0.0\~1.1V(vs. SCE)$. Therefore, Ta film could be used the supercapacitor as a current collector. The irreversible hydrolysis in the supercapacitor occurred over ca. 1.0V(vs.SCE) when the supercapacitor was protonated to 0.5V(vs. SCE). The supercapacitor protonated to 0.5V(vs.SCE) showed good electrochemical properties when it was tested at the potential range of 1.0V in the charge-discharge test. The potential range of the electrodes including the positive and the negative electrode was varied between -0.004 and 0.995V(vs. SCE). The potential ranges of the positive and the negative electrode were $-0.004\~0.515V(vs.\;SCE)\;and\; 0.515\~0.995V(vs.\;SCE)$, respectively.

루테늄 산화물-수계 전해액 수퍼캐패시터의 전위 특성

[ $RuCI_3{\cdot}xH_2O$ ]로부터 제조한 비정질의 $RuO_2{\cdot}nH_2O$을 사용하여 탄탈륨 집전체상의 수퍼캐패시터 전극을 제조하였다. $RuO_2{\cdot}nH_2O$ 전극과 4.8 M 황산 전해액을 사용하여 $RuO_2$ 수퍼캐패시터를 제조하였다. 탄탈륨 박막은 0.0-1.1 V(vs.SCE)에서 안정적임을 AC impedance로 확인하고 수퍼캐패시터에 적용하였다. 루테늄 산화물 수퍼캐패시터는 약 1.0 V(vs. SCE)이상에서 비가역 가수분해 반응이 진행되었다 수퍼캐패시터를 0.5V(vs. SCE)의 protonation leve을 조정하고, 전압범위를 1V로 하여 충방전 시험할 경우 우수한 특성을 나타내었다. 이때 전극전위는 $-0.004\~0.995V(vs.SCE)$의 범위이고 positive 전극 및 negative 전극의 전위범위는 각각 $-0.004\~0.515V(vs.SCE)$ 및 $-0.515\~0.995V(vs.SCE)$이었다.